Note: Descriptions are shown in the official language in which they were submitted.
CA 02488242 2004-12-01 {
WO 03/101984 PCT/EP03/05465
SUBSTITUTED THIOPHENES, METHOD FOR THE PRODUCTION THEREOF,
THEIR USE AS A MEDICAMENT OR DIAGNOSTIC REAGENT, AND A
MEDICAMENT CONTAINING THE SAME
Substituted thiophenes, method for the production thereof, their use as a
medicament
or diagnostic reagent, and a medicament containing the same
The invention relates to compounds of the type of the substituted thiophene
derivatives
of the formula I. Medicaments comprising compounds of this type are of use for
preventing or treating various disorders. Thus, the compounds can be used,
inter alia,
for the treatment of respiratory disorders and snoring, and for improving the
respiratory
drive, for the treatment of acute and chronic disorders, disorders triggered
by ischemic
and/or reperfusion events and by proliferative or fibrotic events, for the
treatment or
prophylaxis of disorders of the central nervous system and lipid metabolism,
and
diabetes, blood coagulation and infection by parasites.
The invention relates to compounds of the formula I,
R3 R5 R7
N
S , )IL, R8
N N R6
R1 R4 H
in which:
R1 and R2
independently of one another are H, F, Cl, Br, I, CN, N02, -(X)n-CgH2q-Z,
cycloalkyl having 3, 4, 5 or 6 carbon atoms, alkenyl having 2, 3 or 4 carbon
atoms, alkenylalkyl having 3 or 4 carbon atoms, ethynyl or alkylalkynyl having
3 or 4 carbon atoms;
n is zero or1;
CA 02488242 2004-12-01
2
X is oxygen, NH, N-CH3, S(O)k;
k is zero, 1 or 2;
q is zero, 1, 2, 3, 4,5or6;
Z is hydrogen or CmF2m+1;
m is zero, 1, 2, 3 or 4;
R3 is hydrogen, methyl, F, Cl, Br, I, CN, S(O)k-CH3, -NO2, -O-CH3;
k is zero, 1 or 2;
R4 is hydrogen, cycloalkyl having 3, 4, 5, or 6 carbon atoms, alkenyl having
2, 3 or
4 carbon atoms, alkenylalkyl having 3 or 4 carbon atoms, ethynyl or
alkylalkynyl having 3 or 4 carbon atoms, -CrH2r - Y;
r is zero, 1, 2, 3 or 4;
Y is hydrogen or trifluoromethyl;
R5 and R6 are hydrogen or together are a bond;.
R7 and R8
independently of one another are (C3-C5)-alkyl, (C2-C5)-alkenyl, (C2-C5)-
alkynyl, (C3-C6)-cycloalkyl or (C4-C6)-cycloalkenyl
or
R7 and R8
together are an alkylene chain comprising 3 to 8 carbon atoms;
where none, some or all of their hydrogen atoms may be replaced by fluorine
atoms;
or
R7 and R8
together are a radical
R12 All
R10
R9
where R5 and R6 together form a bond;
R10 and R11
CA 02488242 2004-12-01
3
independently of one another are hydrogen, fluorine, chlorine,
bromine, methyl, CN, OH, -O-CH3, NO2, NI-12 or -CF3;
R9 and R12
are hydrogen or F;
or
one of the substituents R9 and R12
is hydrogen;
and the other is F, Cl, Br, I, CN, NO2, COOH, CO-NR13R14, SO2-
NR13R14, alkenyl having 2, 3 or 4 carbon atoms, alkenylalkyl having 3
or 4 carbon atoms, ethynyl, alkylalkynyl having 3 or 4 carbon atoms or
-(X)n - CgH2q-Z;
R13 and R14
are identical or different hydrogen or alkyl having 1, 2, 3 or 4
carbon atoms;
or
R13 and R14 together with the nitrogen to which they are attached
form a saturated 5-, 6- or 7-membered ring;
n is zero or1;
X is oxygen, NH, N-CH3, S(O)k;
k is zero, 1 or 2;
q is zero, 1, 2, 3, 4, 5 or 6;
and
Z is hydrogen or CmF2m+1;
m is zero, 1, 2, 3 or 4;
and their pharmaceutically acceptable salts, and their trifluoroacetic acid
salts.
One embodiment relates to compounds of the formula I in which
R1 and R2
independently of one another are H, F, Cl, Br, I, ON, NO2, -(X)n - CqH2q - Z,
cycloalkyl having 3, 4, 5 or 6 carbon atoms, alkenyl having 2, 3 or 4 carbon
CA 02488242 2004-12-01
4
atoms, alkenylalkyl having 3 or 4 carbon atoms, ethynyl or alkylalkynyl having
3 or 4 carbon atoms;
n is zero or1;
X is oxygen, NH, N-CH3, S(O)k;
k is zero, 1 or 2;
q is zero, 1, 2, 3, 4, 5 or 6;
Z is hydrogen or CmF2m+l;
m is zero, 1, 2, 3 or 4;
R3 is hydrogen, methyl, .F, Cl, Br, I, CN, S.(O)k-CH3, -NO2, -0- CH3;
R4 is hydrogen, cycloalkyl having 3, 4, 5, or 6 carbon atoms, alkenyl having
2, 3 or
4 carbon atoms, alkenylalkyl having 3 or 4 carbon atoms, ethynyl or
alkylalkynyl having 3 or 4 carbon atoms, -CqH2q - Z;
q is zero, 1, 2, 3 or 4;
Z is hydrogen or trifluoromethyl;
R5 and R6
are hydrogen or together are a bond;
R7 and R8
independently of one another are (C3-C5)-alkyl, (C2-C5)-alkenyl, (C2-C5)-
alkynyl, (C3-C6)-cycloalkyl or (C4-C6)-cycloalkenyl
or
R7 and R8
together are an alkylene chain comprising 3 to 8 carbon atoms;
where none, some or all of their hydrogen atoms may be replaced by fluorine
atoms;
or
R7 and R8
together are a radical
CA 02488242 2004-12-01
R12 R11
R10
R9
where R5 and R6 together form a bond;
R9, R10 and R11
independently of one another are hydrogen, fluorine, chlorine,
5 bromine, methyl, CN, OH, -0-CH3, NO2, NH2 or -CF3;
R9 and R 12
are hydrogen;
or
one of the substituents R9 and R12
is hydrogen;
and the other is F, Cl, Br, I, ON, NO2, COOH, CO-NR13R14,
S02-NR13R14, alkenyl having 2, 3 or 4 carbon atoms,
alkenylalkyl having 3 or 4 carbon atoms, ethynyl, alkylalkynyl
having 3 or 4 carbon atoms or -(X)n - CqH2q-Z;
R13andR14
are identical or different hydrogen or alkyl having 1, 2, 3 or 4
carbon atoms;
n is zero or1;
X is oxygen, NH, N-CH3, S(O)k;
k is zero, 1 or 2;
q is zero, 1, 2, 3, 4, 5 or 6;
and
Z is hydrogen or CmF2m+1;
m is zero, 1, 2, 3 or 4;
and their pharmaceutically acceptable salts, and their trifluoroacetic acid
salts.
Preference is given to compounds of the formula I, in which:
CA 02488242 2004-12-01
6
R1 and R2
independently of one another are H, F, Cl, Br, CH3, CF3 ,S02CH3, S02NH2;
but where at most one of the substituents R1 and R2 is hydrogen;
R3 is hydrogen, F or Cl;
R4 is hydrogen, alkyl having 1, 2, 3 or 4 carbon atoms, or cyclopropyl;
R5 and R6
are hydrogen or together are a bond;
R7 and R8
together are an alkylene chain comprising 3, 4, 5, 6, 7 or 8 carbon atoms;
or
R7 and R8
together are a radical
R12 R11
R10
R9
where R5 and R6 together form a bond;
R10andR11
independently of one another are hydrogen, OH, fluorine or chlorine;
R9 and R12
are hydrogen;
or
one of the substituents R9 and R12
is hydrogen;
and the other is F, Cl, Br, CN, COOH, CO-NR13R14, S02-NR13R14
or -(X)n - CgH2q-Z;
R13 and R14
are identical or different hydrogen or methyl;
n is zero or 1;
X is oxygen, NH, N-CH3 or S(O)k;
k is zero, 1 or 2;
CA 02488242 2004-12-01
7
q is zero, 1, 2, 3 or 4;
Z is hydrogen or CF3;
and their pharmaceutically acceptable salts, and their trifluoroacetic acid
salts.
Particular preference is given to compounds of the formula I in which:
R1 and R2
independently of one another are F, Cl, Br, CH3 or CF3;
R3 is hydrogen;
R4 is hydrogen, methyl, ethyl;
R5 and R6
are hydrogen or together are a bond;
R7 and R8
together are an alkylene chain comprising 3, 4, 5, 6, 7 or 8 carbon atoms;
or
R7 and R8
together are a radical
R12 R11
/ R10
9
where R5 and R6 together form a bond;
R10 and R11
independently of one another are hydrogen, OH or fluorine;
R9 and R12
are hydrogen;
or
one of the substituents R9 and R12
is hydrogen;
and the other is F, Cl, Br or -(X)n - CgH2q-Z;
n is zero or1;
X is oxygen, NH, N-CH3 or S(O)k;
CA 02488242 2004-12-01
8
k is zero, 1 or 2;
q is zero or 1;
Z is hydrogen or CF3;
and their pharmaceutically acceptable salts, and their trifluoroacetic acid
salts.
Very particular preference is given to the following compounds of the formula
I,
selected from the group consisting of:
trans-R,R-2-chloro-3N-(3a,4,5,6,7,7a-hexahydro-1 H-2-benzimidazolyl)-4-methyl-
3-
thienylamine,
trans-R, R-2-bromo-3N-(3a,4,5,6,7,7a-hexahydro-1 H-2-benzimidazolyl)-4-methyl-
3-
thienylamine,
2-chloro-3N-(2-benzimidazolyl)-4-methyl-3-thienylamine,
2-bromo-3N-(2-benzimidazolyl)-4-methyl-3-thienylamine,
2-chloro-3N-(4-methyl-2-benzimidazolyl)-4-methyl-3-thienylamine,
2-chloro-3N-(5-fluoro-2-benzimidazolyl)-4-methyl-3-thienylamine,
2-chloro-3N-(4-chloro-2-benzimidazolylamino)-4-methylthiophene,
2-bromo-3N-(4-chloro-2-benzimidazolylamino)-4-methylthiophene,
2-bromo-3N-(4-fluoro-2-benzimidazolylamino)-4-methylthiophene,
2-chloro-3N-(4-f luoro-2-benzimidazolylamino)-4-methylthiophene,
2-chloro-3N-(4-hydroxy-2-benzimidazolylamino)-4-methylthiophene,
(1 H-benzimidazol-2-yl)-(2-chloro-4-methylthiophen-3-yl)-methylamine,
(2-bromo-4-methylthiophen-3-yl)-(5-fluoro-1 H-benzimidazol-2-yl)-amine,
2-chloro-3N-(2-benzimidazolylamino)-4-methylthiophene,
2,4-dichloro-3N-(2-benzimidazolylamino)thiophene,
2-bromo-4-chloro-3N-(2-benzimidazolylamino)thiophene,
2,4-dichloro-3N-(4-methyl-2-benzimidazolylamino)thiophene,
trans-R,R-2,4-dichloro-3N-(3a,4,5,6,7,7a-hexahydro-1 H-2-benzimidazolyl)-3-
thienylamine,
or
2,4-dichloro-3N-(4-chloro-2-benzimidazolylamino)thiophene
and their pharmaceutically acceptable salts, for example the hydrochloride or
the
CA 02488242 2004-12-01
9
hydrobromide or the methanesulfonate of each of the compounds.
The compounds of the formula I can be present in the form of their salts.
Suitable acid
addition salts are salts of all pharmacologically acceptable acids, for
example halides,
in particular hydrochlorides, hydrobromides, lactates, sulfates, citrates,
tartrates,
acetates, phosphates, methylsulfonates, benzenesulfonates, p-
toluenesulfonates,
adipinates, fumarates, gluconates, glutamates, glycerolphosphates, maleates,
benzoates, oxalates and pamoates. This group also corresponds to the
physiologically
acceptable anions; but also trifluoroacetates. If the compounds contain an
acid group,
they are capable of forming salts with bases, for example as alkali metal
salts,
preferably sodium or potassium salts, or as ammonium salts, for example as
salts with
ammonia or organic amines or amino acids. They can also be present as
zwitterion.
If the compounds of the formula I contain one or more centers of asymmetry,
the
compounds can independently be both S- and R-configured. The compounds can be
present as optical isomers, as diastereomers, as racemates or as mixtures
thereof.
The compounds of the formula I can furthermore be present as tautomers or as a
mixture of tautomeric structures. This refers, for example, to the following
tautomers:
R3 R2 R5 R7 R3 R2 R5 R7 R3 R2 R5 R7
N HN HN
S N R8 S 1\ R$ S R8
N R6 N N R6 N R6
R1 R4 H R1 R4 R1 H
(if R4 = H)
Alkyl radicals can be straight-chain or branched. This also applies when they
carry
substituents or are present as substituents of other radicals, for example in
fluoroalkyl
radicals or alkoxy radicals. Examples of alkyl radicals are methyl, ethyl, n-
propyl,
isopropyl (= 1-methylethyl), n-butyl, isobutyl (= 2-methylpropyl), sec-butyl
(= 1-methyl-
CA 02488242 2004-12-01
propyl), tert-butyl (= 1,1-dimethylethyl), n-pentyl, isopentyl, tert-pentyl,
neopentyl or
hexyl. Preferred alkyl radicals are methyl, ethyl, n-propyl, isopropyl, n-
butyl, tert-butyl,
n-pentyl, n-hexyl. In alkyl radicals, one or more, for example 1, 2, 3, 4, 5,
6, 7, 8 or 9,
hydrogen atoms may be substituted by fluorine atoms. Examples of such
fluoroalkyl
5 radicals are trifluoromethyl, 2,2,2-trifluoroethyl, pentafluoroethyl,
heptafluoroisopropyl.
Substituted alkyl radicals may be substituted in any positions.
Alkenyl radicals may be straight-chain or branched. This also applies when
they are
present as substituents, for example in alkenylalkylene. The alkenyl radicals
can be
10 unsaturated in different positions. Examples of alkenyl radicals are
ethenyl, propenyl or
butenyl.
Alkynyl radicals can be straight-chain or branched. This also applies when
they are
present as substituents, for example in alkynylalkylene. The alkynyl radicals
can be
unsaturated in different positions. Examples of alkynyl radicals are ethynyl,
propynyl or
butynyl.
Examples of cycloalkyl radicals are cyclopropyl, cyclobutyl, cyclopentyl or
cyclohexyl.
Substituted cycloalkyl radicals can be substitued in any positions. The
cycloalkyl
radicals may also be present branched as alkylcycloalkyl or cycloalkylalkyl.
Also described are methods for preparing compounds according to the invention.
Thus, the substances described by formula I can be prepared in a manner known
to
the person skilled in the art from the isothiocyanate 11 parent compounds and
the
appropriate diamines Ill..
R3 R2
R5 R7
S ~,= 2
N=C=S R8
R1 H 2 N R6
II Ill
CA 02488242 2004-12-01
11
The thiourea derivative which is formed as an intermediate is cyclized using
methyliodide (Synthesis, 1974, 41 - 42) or carbodiimide (Synthesis, 1977, 864 -
865)
or using p-toluenesulfonyl chloride to give the corresponding compound of the
formula I. If the isothiocyanates II employed here are not commercially
available, they
can be prepared in a manner known from the literature from the corresponding
aminothiophene derivatives, using methods known to the person skilled in the
art, for
example by treatment with thiophosgene (J. Med. Chem., 1975, 18, 90-99) or
thiocarbonyl diimidazole (Justus Liebigs Ann. Chem., 1962, 657, 104).
In addition to the isothiocyanates II described above, it is also possible to
successfully
react the isocyanates IV
R3
R2
S
N=C=O
R1 IV
with amines of the type of formula III to give the compounds of the formula I.
Here, the
urea derivative which is formed as an intermediate is cyclized using
phosphorus
oxychloride to give the corresponding compounds of the formula I.
In the present invention, it was surprisingly possible to demonstrate that the
compounds described are potent inhibitors of the sodium/proton exchanger
(NHE), in
particular the sodium/proton exchanger of subtype 3 (NHE3).
The NHE3 inhibitors known to date are derived from compounds of the
acylguanidine
type (EP825178), of the norbornylamine type (DE199 60 204), of the 2-guanidino-
quinazoline type (WO 0179186) or of the benzamidine type (WO0121582,
WO0172742). Squalamine, which has also been described as NHE3 inhibitor
(M. Donowitz et al. Am. J. Physiol. 276 (Cell Physiol. 45): C136 - C144), is,
according
to current understanding, not, unlike the compounds of the formula I,
effective
immediately, but rather via an indirect mechanism and thus reaches its maximum
potency only after one hour. Such NHE3 inhibitors which act by a different
mechanism
CA 02488242 2004-12-01
12
are therefore suitable for use as combination partners for the present
compounds
according to the invention.
Clonidine, which is similar to the compounds described here, is known as a
weak NHE
inhibitor. However, its action on the NHE3 of the rat is, with a half-maximal
inhibitory
concentration (IC50) of 620 NM, extremely moderate. In contrast, it shows a
certain
selectivity for the NHE2 (J. Orlowski et al. J. Biol. Chem. 268, 25536). It
would
therefore be more accurate to refer to clonidine as an NHE2 inhibitor. In
addition to the
weak NHE action, clonidine has a high affinity for the adrenergic alpha2
receptor and
the imidazoline 11 receptor, mediating a strong hypotensive action (Ernsberger
et at.,
Eur. J. Pharmacol. 134, 1, 1987).
Clonidine-like compounds having a thiophene ring instead of the phenyl ring
are known
from DE1941761. These known compounds differ from the structures of the
formula I
described herein in that they have considerably smaller radicals R7 and R8 and
in
particular by the fact that R7 and R8 are not capable of forming a joint ring.
By these differences in the substituents R7 and R8, it is possible to
eliminate the
undesirable clonidine-like cardiovascular effects described above, which are
mediated
by the alpha-adrenoceptor action. At the same time, owing to these differences
in the
substituents, the NHE-inhibiting properties of the compounds described herein
are
enhanced to the micromolar and submicromolar range, whereas the compounds
known from DE1941761 show only extremely weakly pronounced NHE-inhibiting
effects, if any. Thus the main representative compound from DE1941761, the
hypotensive agent thiamenidine selected as development product, has, in each
case at
300 NM, no inhibiting effects on the NHE-subtypes NHE1, NHE2, NHE3 and NHE5
which were tested.
Compounds of the formula I are distinguished in that they inhibit the cellular
sodium/proton exchanger, and in particular by their NHE3-inhibitory action.
NHE3 is found in the body of various species, preferably in the gall bladder,
the
intestine and the kidney (Larry Fliegel et al., Biochem. Cell. Biol. 76: 735 -
741, 1998),
CA 02488242 2010-09-08
13
but can also be detected in the brain (E. Ma et al., Neuroscience 79: 591 -
603).
Owing to the NHE-inhibitory properties, the compounds of the formula I are
suitable for
the prevention and treatment of diseases caused by an activation of NHE or by
an
activated NHE, and of diseases which are sequelae of damage caused by NHE.
Since NHE inhibitors act predominantly via influencing cellular pH regulation,
they can
be combined in a favorable manner with other compounds which also regulate the
intracellular pH, suitable combination partners being inhibitors of the enzyme
group of
the carbonate dehydratases, inhibitors of the bicarbonate-ion-transporting
systems,
such as the sodium bicarbonate cotransporter (NBC) or the sodium-dependent
chloride/bicarbonate exchanger (NCBE), and also NHE inhibitors having
inhibitory
action on other NHE subtypes, since they can modulate or enhance the
pharmacologically relevant pH-regulating effects of the NHE inhibitors
described
herein.
The use of the compounds according to the invention relates to the prevention
and
treatment of acute and chronic diseases in veterinary and human medicine. The
pharmacological action of the compounds of the formula I is characterized in
that they
induce an improvement in the respiratory drive. They can therefore be used in
the
treatment of disturbed respiratory conditions which may, for example, occur in
the
following clinical conditions and diseases: disturbed central respiratory
drive (e.g. central
sleep apnea, sudden infant death, postoperative hypoxia), respiratory
disorders
associated with sleeping, muscular-related respiratory disorders, respiratory
disorders
after long-term ventilation, respiratory disorders during adaptation in a high
mountain
area, obstructive and mixed forms of sleep apnea, acute and chronic lung
diseases with
hypoxia and hypercapnia.
The compounds additionally increase the muscle tone of the upper airways, so
that
snoring is suppressed. As a result, the compounds mentioned are advantageously
used for preparing a medicament for the prevention and treatment of sleep
apnea and
muscular-related respiratory disturbances and for preparing a medicament for
the
prevention and treatment of snoring.
CA 02488242 2004-12-01
14
A combination of an NHE inhibitor of the formula I with a carboanhydrase
inhibitor (e.g.
acetazolamide) may prove to be advantageous, the latter producing metabolic
acidosis
and thereby already, increasing respiratory activity, as a result of which an
increased
action and decreased use of active compound may be achieved.
Owing to their NHE3-inhibitory action, the compounds according to the
invention spare
cellular energy resources which, during toxic and pathogenic events, are
rapidly
depleted, thus resulting in cell damage or cell death. Here, the high-energy
ATP-
consuming resorption of sodium in the proximal tubulus is, under the influence
of the
compounds of the formula I, temporarily switched off, and the cell is thus
able to
survive an acute pathogenic, ischemic or toxic situation. The compounds are
therefore
suitable by way of example for use as drugs for treating ischemic noxa, for
example
acute kidney failure.
Furthermore, the compounds are also suitable for treating all chronic renal
disorders
and forms of nephritis which, as a consequence of increased elimination of
protein,
result in chronic kidney failure. Accordingly, the compounds of the formula I
are
suitable for preparing a_medicament for the treatment of diabetic late damage,
diabetic
nephropathy and chronic renal disorders, in particular all inflammations of
the kidney
(nephritides) associated with increased elimination of protein/albumin.
It has been shown that the compounds used according to the invention have mild
laxative action and, accordingly, can also be used advantageously as laxatives
or for
the prophylaxis of intestinal obstruction.
Furthermore, the compounds according to the invention can be used
advantageously
for the prevention and therapy of acute and chronic disorders of the
intestinal tract
triggered, for example, by ischemic states in the intestinal region and/or by
subsequent
reperfusion or by states and events of inflammation. Such complications can
occur, for
example, by lack of intestinal peristalsis, as is frequently observed, for
example, after
surgical interventions, in the case of bowel obstruction or in cases of
strongly reduced
intestinal motility.
CA 02488242 2010-09-08
Using the compounds according to the invention, it is possible to prevent
gallstone
formation. The compounds according to the invention are suitable for treating
disorders
related to gall function.
5 The compounds according to the invention are also suitable for treating
infection by
ectoparasites.
The NHE inhibitors according to the invention are generally suitable for
treating
diseases caused by ischemia and by reperfusion.
As a result of their pharmacological properties, the compounds according to
the
invention are suitable for use as antiarrhythmics.
Owing to their cardioprotective component, the NHE inhibitors of the formula I
are highly
suitable for infarct prophylaxis and infarct treatment and for treatment of
angina pectoris,
and they also inhibit, or strongly reduce, in a preventative manner, the
pathophysiological processes which contribute to ischemicaliy induced damage,
in
particular those which trigger ischemicaliy induced cardiac arrhythmias. Owing
to their
protective action against pathological hypoxic and ischemic situations, the
compounds
of the formula I used according to the invention can, as inhibitors of the
cellular Na/H
exchange mechanism, be used as medicaments for treating all acute or chronic
damage
caused by ischemia, or diseases induced primarily or secondarily by this
damage.
This relates to their use as medicaments for surgical interventions. Thus, the
compounds according to the invention can be used for organ transplantations,
where
the compounds can be used both for protecting the organs in the donor before
and
during removal, for protecting organs that have been removed, for example
during
treatment with or storage in physiological bath fluids, and also during
transfer into the
recipient organism pretreated with compounds of the formula I.
The compounds are also useful medicaments with protective action during
angioplastic
surgical interventions, for example on the heart, but also in peripheral
organs and
vessels.
Since NHE inhibitors protect human tissue and organs not only effectively
against
CA 02488242 2010-09-08
16
damage caused by ischemia and reperfusion but also against the cytotoxic
action of
medicaments used in particular in cancer therapy and the therapy of autoimmune
diseases, the combined administration with compounds of the formula I is
suitable for
suppressing or reducing the cytotoxic effects of a therapy. By reducing the
cytotoxic
effects, in particular cardiotoxicity, by comedication with NHE inhibitors it
is furthermore
possible to increase the dose of the cytotoxic therapeutics and/or to prolong
medication
with such medicaments. The therapeutic benefit of such a cytotoxic therapy can
be
enhanced considerably, by combination with NHE inhibitors. The compounds of
the
invention are suitable for use as medicaments for the treatment of cancer.
The compounds of the formula I are suitable in particular for improving the
therapy with
medicaments having an undesirable cardiotoxic component.
Owing to their protective action against ischemically induced damage, the
compounds
according to the invention are also suitable for use as medicaments for
treating
ischemias of the nervous system, in particular the central nervous system,
where they
can be used, for example, for treating stroke or cerebral edema. In addition,
the
compounds according to the invention are also suitable for use as medicaments
for
treating disorders of the central nervous system.
The compounds of formula I are also suitable for the therapy and prophylaxis
of
diseases and disorders induced by overexcitability of the central nervous
system, in
particular for the treatment of epileptic disorders, centrally induced clonic
and tonic
spasms, states of psychological depression, anxiety disorders and psychoses.
Here, the
NHE inhibitors according to the invention can be used on their own or in
combination
with other substances having antiepileptic action or with antipsychotic active
compounds, or carbonate dehydratase inhibitors, for example acetazolamide, and
also
with other inhibitors of NHE or of the sodium-dependent chloride/bicarbonate
exchanger (NCBE).
In addition, the compounds of the formula I according to the invention are
also suitabte
for treating types of shock, such as, for example, of allergic, cardiogenic,
hypovolemic
and bacterial shock.
CA 02488242 2010-09-22
16a
The compounds of the formula I can also be used for the prevention and
treatment of
thrombotic disorders, such as thromboses, since, as NHE inhibitors, they are
also
capable of inhibiting
CA 02488242 2004-12-01
17
platelet aggregation themselves. In addition, they can prevent or inhibit
excessive
release of mediators of inflammation and coagulation, in particular of the von
Willebrand factor and thrombogenic selecting proteins which takes place
following
ischemia and reperfusion. It is thus possible to reduce and eliminate
the.pathogenic
effect of significant thrombogenic factors. Accordingly, the NHE inhibitors of
the
present invention can be combined with other compounds having anticoagulative
and/or thrombolytic action, such as, for example, recombinant or natural
tissue
plasminogen activator, streptokinase, urokinase, acetylsalicylic acid,
thrombin
antagonists, factor Xa antagonists, medicaments with fibrinolytic action,
thromboxane
receptor antagonists, phosphodiesterase inhibitors, factor VIIa antagonists,
clopidogrel, ticlopidine, etc. Combined use of the present NHE inhibitors with
NCBE
inhibitors and/or with inhibitors of carbonate dehydratase, such as, for
example, with
acetazolamide, is particularly beneficial.
Furthermore, the compounds of the formula I according to the invention have
strong
inhibiting action on cell proliferation, for example on fibroblast cell
proliferation and
proliferation of smooth vascular muscle cells. The compounds of the formula I
are
therefore useful therapeutics for diseases in which cell proliferation is a
primary or
secondary cause and can therefore be used as antiatherosclerotics, as agents
against
chronic kidney failure and against neoplastic diseases. Thus, they can be used
for
treating organ hypertrophy and hyperplasia, for example of the heart and the
prostate.
Compounds of the formula I are therefore suitable for the prevention and
treatment of
cardiac insufficiency (congestive heart failure = CHF) and for the treatment
and
prevention of prostate hyperplasia and prostate hypertrophy.
The compounds of the formula I furthermore delay or prevent fibrotic
disorders. Thus,
they are excellent agents for treating fibroses of the heart, and also
pulmonary fibrosis,
liver fibrosis, kidney fibrosis and other fibrotic disorders.
Since there is significant elevation of NHE in essential hypertensives, the
compounds
of the formula I are suitable for the prevention and treatment of high blood
pressure
and of cardiovascular disorders.
CA 02488242 2004-12-01
18
Here, they can be used for the treatment of high blood pressure and of
cardiovascular
disorders on their own or with a suitable combination and formulation
cocomponent.
Thus, it is possible, for example, to combine one or more diuretics having
thiazide-like
action, loop diuretics, aldosterone and pseudoaldosterone antagonists, such as
hydrochlorothiazide, indapamide, polythiazide, furosemide, piretanide,
torasemide,
bumetanide, amiloride, triamterene, spironolactone or eplerone, with compounds
of the
formula I. Furthermore, the NHE inhibitors of the present invention can be
used in
combination with calcium antagonists such as verapamil, diltiazem, amlodipine
or
nifedipine, and also with ACE inhibitors, such as, for example, ramipril,
enalapril,
lisinopril, fosinopril or captopril. Further favorable combination partners
include beta-
blockers such as metoprolol, albuterol etc., antagonists of the angiotensin
receptor and
its receptor subtypes, such as losartan, irbesartan, valsartan, omapatrilat,
gemopatrilat, endothelin antagonists, renin inhibitors, adenosine receptor
agonists,
inhibitors and activators of calcium channels, such as glibenclamide,
glimepiride,
diazoxide, cromakalim, minoxidil and its derivatives, activators of the
mitochondrial
ATP-sensitive potassium channel (mitoK(ATP) channel), inhibitors of other
potassium
channels, such as inhibitors of Kv1.5 etc.
Owing to their antiphlogistic action, the NHE inhibitors can be used as
antiinflammatory
agents. Mechanistically interesting is the inhibition of the release of
mediators of
inflammation. Thus, the compounds can be used alone or in combination with an
antiphlogistic agent for the prevention or treatment of chronic and acute
inflammatory
disorders. The combination partners used are advantageously steroidal and non-
steroidal anti inflammatory agents.
Moreover, it has been found that compounds of the formula ,l exert a
beneficial
influence on serum lipoproteins. They can therefore be used for the
prophylaxis and
regression of atherosclerotic changes by excluding a causal risk factor. This
includes
not only primary hyperlipidemias but also certain secondary hyperlipidemias as
are
encountered, for example, in diabetes. Additionally, the compounds of the
formula I
reduce infarcts induced by metabolic anomalies considerably and, in
particular, lead to
a significant reduction in the size and severity of the infarct induced.
CA 02488242 2004-12-01
19
Accordingly, the compounds mentioned are used advantageously for preparing a
medicament for the treatment of hypercholesterolemia, for preparing a
medicament for
the prevention of atherogenesis, for preparing a medicament for the prevention
and
treatment of atherosclerosis, for preparing a medicament for the prevention
and
treatment of diseases induced by elevated cholesterol levels, for preparing a
medicament for the prevention and treatment of diseases induced by endothelial
dysfunction, for preparing a medicament for the prevention and treatment of
hypertension induced by atherosclerosis, for preparing a medicament for the
prevention and treatment of thromboses induced by atherosclerosis, for
preparing a
medicament for the prevention and treatment of ischemic damage and post-
ischemic
reperfusion damage induced by hypercholesterolemia and endothelial
dysfunction, for
preparing a medicament for the prevention and treatment of cardiac
hypertrophies and
cardiomyopathies and congestive heart failure (CHF), for preparing a
medicament for
the prevention and treatment of coronary vascospasms and myocardial infarcts
induced by hypercholesterolemia and endothelial dysfunction, for preparing a
medicament for the treatment of the conditions mentioned in combination with
hypotensive substances, preferably with angiotensin converting enzyme (ACE)
inhibitors and angiotensin receptor antagonists. A combination of an NHE
inhibitor of
the formula I with an active compound that lowers the lipid concentration in
the blood,
preferably an HMG-CoA reductase inhibitor (for example lovastatin or
pravastatin), the
latter having hypolipidemic action, thereby enhancing the hypolipidemic
properties of
the NHE inhibitor of the formula I, has been found to be a favorable
combination with
increased action and reduced use of active compound.
Thus, compounds of the formula I bring about effective protection against
endothelial
damage of various origins. Owing to this protection of the vessels against the
syndrome of endothelial dysfunction, compounds of the formula I are useful
medicaments for the prevention and treatment of coronary vascospasms,
peripheral
vascular diseases, in particular intermittent claudication, of atherogenesis
and
atherosclerosis, of left-ventricular hypertrophy and of dilated
cardiomyopathy, and of
thrombotic disorders.
CA 02488242 2004-12-01
Moreover, NHE inhibitors of the formula I are suitable for treating non-
insulin-
dependent diabetes (NIDDM) where, for example, insulin resistance is
suppressed.
Here, to enhance antidiabetic efficacy and quality of action of the compounds
according to the invention, it may be favorable to combine these compounds
with a
5 biguanide such as metformin, with an antidiabetic sulfonylurea, such as
glyburide,
glimepiride, tolbutamide, etc., a glucosidase inhibitor, a PPAR agonist, such
as
rosiglitazone, pioglitazone, etc., with an insulin product in a different
administration
form, with a DB4 inhibitor, with an insulin sensitizer or with meglitinide.
10 In addition to the acute antidiabetic effects, the compounds of the formula
I counteract
the development of late complications of diabetes, and they can therefore be
used as
medicaments for the prevention and treatment of diabetic late damage, such as
diabetic nephropathy, diabetic neuropathy, diabetic retinopathy, diabetic
cardiomyopathy and other disorders which occur as a result of diabetes. In
this
15 connection, they can be combined advantageously with the antidiabetic
medicaments
described above under the NIDDM treatment. A combination with a favorable
administration form of insulin may be of particular importance.
In addition to the protective effects against acute ischemic events and
subsequent
20 likewise acute reperfusion events, the NHE inhibitors.of the formula I
according to the
invention also have direct therapeutically useful action against disorders and
impairments of the entire mammalian organism which are associated with
manifestations of the chronically progressing aging process and are also
independent
of acute states of hypoperfusion, and may also occur under normal, non-
ischemic
conditions. These pathological age-related manifestations, such as disease,
illness
and death, induced over the long time of aging, which are now accessible to
treatment
with NHE inhibitors, are disorders and disturbances caused to a substantial
extent by
age-related changes in vital organs and their function which become more and
more
important in the aging organism.
Disorders associated with age-related dysfunction and age-related symptoms of
wear
of organs are, for example, inadequate responsiveness and reactivity of the
blood
vessels to contraction and relaxation reactions. This age-related decline in
vascular
CA 02488242 2004-12-01
21
reactivity to constricting and relaxing stimuli, which are an essential
process of the
cardiovascular system and thus of life and health, can be significantly
diminished or
abolished by NHE inhibitors. An important function and a measure of the
maintenance
of vascular reactivity is the blocking or slowing of the age-related
progression of
endothelial dysfunction, which can be abolished highly significantly by NHE
inhibitors.
The compounds of the formula I are thus outstandingly suitable for the
treatment and
prevention of the age-related progression of endothelial dysfunction,
especially of
intermittent claudication. Moreover, the compounds of the formula I are thus
outstandingly suitable for the treatment and prevention of cardiac
insufficiency, of
congestive heart failure (CHF), and for the treatment and in particular for
the
prevention of age-related types of cancer.
Consideration may likewise be given to combination with hypotensive
medicaments,
such as with ACE inhibitors, angiotensin receptor antagonists, diuretics, Ca2+
antagonists, etc., or with metabolism-normalizing medicaments, such as
cholesterol-
lowering agents. The compounds of the formula I are thus suitable for the
prevention of
age-related tissue changes and for prolonging life while maintaining a high
quality of
life.
The compounds of the invention are effective inhibitors of the cellular
sodium/proton
antiporter (Na/H exchanger) which, in numerous disorders (essential
hypertension,
atherosclerosis, diabetes, etc.), is also elevated in cells which are easily
amenable to
measurements, such as, for example, in erythrocytes, platelets or leukocytes.
The
compounds used according to the invention are therefore suitable as excellent
and
simple scientific tools, for example in their use as diagnostic aids for the
determination
and differentiation of particular types of hypertension, but also of
atherosclerosis, of
diabetes and of late complications of diabetes, of proliferative disorders,
etc.
NHE3 inhibitors are furthermore suitable for treating disorders (human and
veterinary)
caused by bacteria and by protozoa. In the case of disorders caused by
protozoa,
particular mention may be made of malaria diseases of man and of coccidiosis
in
poultry.
Moreover, the compounds are suitable as agents for controlling sucking
parasites in
CA 02488242 2004-12-01
22
human and veterinary medicine and in crop protection. Here, the use as an
agent
against blood-sucking parasites in human and veterinary medicine is preferred.
In addition to their value as potent NHE-inhibitors, their pharmacological
properties and
the absence of undesired biological actions, the compounds of the formula I
are also
distinguished by favorable pharmacokinetic properties which make their use as
medicament seem particularly advantageous.
The invention thus relates to medicaments for human, veterinary or
phytoprotective
use which comprise an effective amount of a compound of the formula I and/or a
pharmaceutically acceptable salt thereof alone or in combination with other
pharmacologically active compounds or medicaments.
Medicaments comprising a compound I can be administered, for example, orally,
parenterally, intramuscularly, intravenously, rectally, nasally, by
inhalation,
subcutaneously or by a suitable transcutaneous administration form, with the
preferred
administration being dependent on the particular appearance of the disorder.
Here, the
compounds I can be used alone or together with pharmaceutical excipients, both
in
veterinary medicine and in human medicine and in crop protection.
Excipients suitable for the desired pharmaceutical formulation are familiar to
the skilled
worker on the basis of his expert knowledge. Besides solvents, gel formers,
suppository bases, tablet excipients and other active ingredient carriers, it
is possible
to use, for example, antioxidants, dispersants, emulsifiers, antifoams,
masking flavors,
preservatives, solubilizers or colorants.
For a form for oral use, the active compounds are mixed with the additives
suitable for
this purpose, such as carriers, stabilizers or inert diluents, and converted
by
conventional methods into suitable dosage forms such as tablets, coated
tablets, two-
piece capsules, aqueous, alcoholic or oily solutions. Examples of inert
carriers which
can be used are gum arabic, magnesia, magnesium carbonate, potassium
phosphate,
lactose, glucose or starch, especially corn starch. Preparation can moreover
take place
CA 02488242 2004-12-01
23
both as dry and as wet granules. Examples of suitable oily carriers or
solvents are
vegetable or animal oils such as sunflower oil or fish liver oil.
For subcutaneous, percutaneous or intravenous administration, the active
compounds
used are converted into a solution, suspension or emulsion, if desired with
the
substances customary for this purpose, such as solubilizers, emulsifiers or
other
excipients. Examples of suitable solvents are: water, physiological saline or
alcohols,
for example ethanol, propanol, glycerol, and also sugar solutions, such as
glucose or
mannitol solutions, or else a mixture of the various solvents mentioned.
Suitable as pharmaceutical formulation for administration in the form of
aerosols or
sprays are, for example, solutions, suspensions or emulsions of the active
compound
of the formula I in a pharmaceutically acceptable solvent, such as, in
particular, ethanol
or water, or a mixture of such solvents.
The formulation may, if required, also comprise other pharmaceutical
excipients such
as surfactants, emulsifiers and stabilizers, and a propellant gas. Such a
preparation
normally contains the active compound in a concentration of about 0.1 to 10,
in
particular of about 0.3 to 3% by weight.
The dosage of the active compound of the formula I to be administered and the
frequency of administration depend on the potency and duration of action of
the
compounds used; also on the nature and severity of the disease to be treated,
and on
the sex, age, weight and individual response of the mammal to be treated.
On average, the daily dose of the compound of the formula I for a patient
weighing
about 75 kg is at least 0.001 mg/kg, preferably 0.1 mg/kg, up to a maximum of
mg/kg, preferably 1 mg/kg, of body weight. In acute situations, for example
immediately after suffering high-altitude breathing disorders, it may even
become
necessary for the dosages to be higher. Especially on i.v. use, for example
for an
30 infarct patient in an intensive care unit, up to 200 mg/kg per day may be
necessary.
The daily dose can be divided into one or more, for example up to 4,
individual doses.
CA 02488242 2004-12-01
24
Description of the experiments and examples:
If the compounds are enantiomerically pure, the configuration and/or the sign
of the
optical rotation is given. If these data are missing, the compounds are
racemates or
not optically active.
The retention times (Rt) given below refer to LCMS measurements with the
following
parameters:
Analytical methods:
A
stationary phase: Merck Purospher 3/12 x 55 mm
mobile phase: 95% H2O (0.1 % HCOOH) -- 95% acetonitrile (0.1 %
HCOOH); 5 min -+ 95% acetonitrile (0.1 % HCOOH); 2 min
-~ 95% H2O (0.1% HCOOH); 1 min; 0.45 ml/min.
B
stationary phase: =YMC J'sphere H80 -4/12.1 x 33 mm
mobile phase: 95% H2O (0.1 % HCOOH) 95% acetonitrile (0.08%
HCOOH); 2.5 min -+ 95% acetonitrile (0.08% HCOOH); 0.5
min -* 95% H2O (0.1 % HCOOH); 0.5 min; 1.3 ml/min.
C
stationary phase: YMC J'sphere H80, 4N, 2.1 x 20 mm
mobile phase: 90% H2O (0.05% TFA) --* 95% acetonitrile; 1.9 min; -* 95%
acetonitrile 0.5 min; I milmin.
D
stationary phase: Merck Purospher 3p 2 x 55 mm
mobile phase: 95% H2O (0.1 % HCOOH)-+ 95% acetonitrile (0.1 %
HCOOH); 3.4 min -* 95% acetonitrile (0.1 % HCOOH);
1 min -* 95% H2O (0.1% HCOOH); 0.2 min; 0.75 ml/min.
E
stationary phase: Merck Purospher 3p 2 x 55 mm
CA 02488242 2004-12-01
mobile phase: 95% H2O (0.05% CF3COOH)-3 95% acetonitrile (0.05%
CF3COOH); 3.4 min - 95% acetonitrile (0.05%
CF3COOH); 1 min; 0.75 ml/min.
F
5 stationary phase: YMC J'sphere H80, 4w, 2.1 x 20 mm
mobile phase: 96% H2O (0.05% CF3COOH)--> 95% acetonitrile; 2 min; -~
95% acetonitrile 0.4 min; 1 ml/min.
Preparative HPLC was carried out under the following conditions:
10 stationary phase: Merck Purospher RP18 (10,uM) 250 x 25 mm
mobile phase: 90% H2O (0.05% TFA)-* 90% acetonitrile; 40 min;
25 ml/min
Example 1: 3N-(5-Fluoro-2-benzimidazolyl)-4-methyl-3-thienylamine
hydrochloride
x HC!
F \>- H
I N
H
15 S
a) 4-Methyl-3-thienyl isothiocyanate
is obtained by reacting equimolar amounts of 3-amino-4-methylthiophene and
N,N'-thiocarbonyldiimidazole in anhydrous tetrahydrofuran (THF) by stirring
the
20 reaction mixture at room temperature for 5 hours and then allowing the
mixture to
stand at room temperature overnight. 4-Methyl-3-thienyl isothiocyanate is
isolated by
distillative removal of the solvent under reduced pressure using a rotary
evaporator,
dissolving the residue in ethyl acetate and washing the organic phase
repeatedly with
water. The organic phase is dried over sodium sulfate and the organic solvent
is then
25 distilled off under reduced pressure using a rotary evaporator, giving 4-
methyl-3-thienyl
isothiocyanate as a brown oily residue. 4-Methyl-3-thienyl isothiocyanate can
be used
without further purification.
CA 02488242 2004-12-01
26
b) N-(2-Amino-5-fluorophenyl)-N'-(4-methyl-3-thienyl)thiourea
0.02 mol of 4-fluoro-1,2-diaminobenzene is added to a solution of 0.02 mol of
4-methyl-3-thienyl isothiocyanate in 60 ml of anhydrous THF. The reaction
mixture is
stirred at room temperature for 2 hours and then allowed to stand overnight,
and the
solvent is then distilled off under reduced pressure using a rotary evaporator
and the
oily residue is purified on a silica gel column using a mixture of identical
proportions of
toluene and ethyl acetate.
Brown crystalline solid. M.p. 180 C.
c) 3N-(5-Fluoro-2-benzimidazolyl)-4-methyl-3-thienylamine hydrochloride
A molar excess (about 1.5 to 4 mol) of methyl iodide is added to 1.5 g (0.0053
mol) of
N-(2-amino-5-fluorophenyl)-N'-(4-methyl-3-thienyl)thiourea in 50 ml of
anhydrous
-ethanol, and the mixture is boiled at reflux for 5 hours. The mixture is
allowed to stand
at room temperature overnight and the ethanol is then distilled off under
reduced
pressure using a rotary evaporator, water is added to the residue and the pH
is
adjusted to 8-9 using saturated aqueous sodium bicarbonate solution. The
mixture is
extracted repeatedly with ethyl acetate, the organic phase is washed with
water and
dried over sodium sulfate, the solvent is distilled off under reduced pressure
using a
rotary evaporator and the residue is purified by silica gel column
chromatography using
a solvent mixture of identical proportions of ethyl acetate and toluene-
(hereinbelow
referred to as "mixture 2") as mobile phase. The oily product obtained after
distillative
removal of the organic solvent is dissolved in ethyl acetate and made highly
acidic
using a saturated solution of hydrogen chloride in dry diethyl ether, and the
precipitate
that crystallizes out is, after relatively long standing, filtered off.
Crystalline solid, m.p.
192 +/- 2 C.
Example 2: 2-Chloro-3N-(5-fluoro-2-benzimidazolyl)-4-methyl-3-thienylamine
hydrochloride and 2,5-dichloro-3N-(5-fluoro-2-benzimidazolyl)-4-methyl-
3-thienylamine hydrochloride
CA 02488242 2004-12-01
27
xHCI xHCI
F N F N H
~' )\ H CI
CI S CI S
{
A solution of 0.24 g (0.0018 mol) of N-chlorosuccinimide in 15 ml of glacial
acetic acid
is added dropwise to a solution of 0.5 g (0.0018 mol) of 3N-(5-flucro-2-
benzimidazolyl)-
4-methyl-3-thienylamine hydrochloride in 25 ml of glacial acetic acid, the
reaction
mixture is stirred at room temperature for about 2 to 3 hours and the solvent
is distilled
off under reduced pressure using a rotary evaporator. Water is added to the
residue
and the mixture is then made alkaline using 2N NaOH and extracted with ethyl
acetate,
the organic phase is washed with water and dried over sodium sulfate and the
solvent
is distilled off under reduced pressure using a rotary evaporator. The
resulting oily
residue is, by medium pressure column chromatography, using a solvent mixture
of
parts of ethyl acetate, 10 parts of n-heptane and 3 parts of glacial acetic
acid
(hereinbelow referred to as "mixture 17") as mobile phase, separated and
treatment
with a solution of hydrogen chloride gas gives:.
15 2-chloro-3N-(5-fluoro-2-benzimidazolyl)-4-methyl-3-thienylamine
hydrochloride from
fraction 1 and 2: colorless to slightly yellowish crystalline product, m.p.
200-202 C,
2,5-dichloro-3N-(5-fluoro-2-benzimidazolyi)-4-methyl-3-thienylamine
hydrochloride
from fraction 3: colorless to slightly yellowish crystalline product, m.p. 286-
288 C.
20 Example 3: 3N-(5,6-Dichloro-2-benzimidazolyl)-4-methyl-3-thienylamine
hydrochloride
x HCI
CI ~ CN
CS
I `}-b
a) N-(2-Amino-4,5-dichlorophenyl)-N'-(4-methyl-3-thienyl)thiourea
is obtained analogously to the reaction described in example 1 b) from 4-
methyl-
CA 02488242 2004-12-01
28
3-thienyl isothiocyanate and 4,5-dichloro-1,2-diaminobenzene. Crystalline
solid,
m.p. 310-320 C.
b) 3N-(5,6-Dichloro-2-benzimidazolyl)-4-methyl-3-thienylamine hydrochloride
is obtained analogously to the procedure described in example 1 c) from N-(2-
amino-
4,5-dichlorophenyl)-N'-(4-methyl-3-thienyl)thiourea and methyl iodide.
Crystalline solid, m.p. 290-294 C.
Example 4: 3N-(2-Benzimidazolyl)-4-methyl-3-thienylamine hydrochloride
x HCI
(::CN
l\
S
a) N-(2-Aminophenyl)-N'-(4-methyl-3-thienyl)thiourea
is obtained analogously to the reaction described in example 1 b) from 4-
methyl-
3-thienyl isothiocyanate and 1,2-diaminobenzene. Crystalline solid having a
1st m.p. of
177-182 C, followed by another crystallization and 2nd m.p. 285-290 C.
b) 3N-(2-Benzimidazolyl)-4-methyl-3-thienylamine hydrochloride
is obtained analogously to the procedure described in example 1 c) from
N-(2-aminophenyl)-N'-(4-methyl-3-thienyl)thiourea and methyl iodide.
Crystalline solid following recrystallization from ethyl acetate/ethanol, m.p.
194-200 C.
Example 5: 3N-(-4-Fluoro-2-benzimidazolyl)-4-methyl-3-thienylamine
hydrochloride
F xHC!
N
S
a) 3-Fluoro-1,2-diaminobenzene
is obtained as an oily amorphous product by hydrogenation of 3-fluoro-2-
nitrophenyl
hydrazine (prepared by reaction of 2,6-difluoronitrobenzene with hydrazine
hydrate)
CA 02488242 2004-12-01
29
using hydrogen and 10% palladium on carbon catalyst in methanol at room
temperature and atmospheric pressure.
b) N-(2-Amino-3-fluorophenyl)-N'-(4-methyl-3-thienyl)thiourea
is obtained analogously to the reaction described in example 1 b) from 4-
methyl-
3-thienyl isothiocyanate and 3-fluoro-1,2-diaminobenzene. Crystalline solid,
point of
decomposition > 240 C.
c) 3N-(-4-Fluoro-2-benzimidazolyl)-4-methyl-3-thienylamine hydrochloride
is obtained analogously to the procedure described in example 1 c) from N-(2-
amino-
3-fluorophenyl)-N'-(4-methyl-3-thienyl)thiourea and methyl iodide. Amorphous
precipitate which crystallizes under acetone. Crystalline solid, m.p. 220-230
C.
Example 6: 3N-(4,6-Difluoro-2-benzimidazolyl)-4-methyl-3-thienylamine
hydrochloride
F x HCI
N
F N
a) N-(2-Amino-3,5-difluorophenyl)-N'-(4-methyl-3-thienyl)thiourea
is obtained analogously to the reaction described in example 1 b) from 4-
methyl-
3-thienyl isothiocyanate and 3,5-difluoro-1,2-diaminobenzene. Crystalline
solid, 1st
melting point: 178-182 C, another crystallization with 2nd m.p.: 299-301 C.
b) 3N-(4,6-Difluoro-2-benzimidazolyl)-4-methyl-3-thienylamine hydrochloride
is obtained analogously to the procedure described in example 1 c) from N-(2-
amino-
3,5-difluorophenyl)-N'-(4-methyl-3-thienyl)thiourea and methyl iodide.
Amorphous
precipitate which crystallizes under ethyl acetate. Crystalline solid, m.p.
232-234 C.
CA 02488242 2004-12-01
Example 7: 3N-(4,5,6,7-Tetrafluoro-2-benzimidazolyl)-4-methyl-3-thienylamine
hydrochloride
F x HCI
F N
F
5 a) N-(2-Amino-3,4,5,6-tetrafluorophenyl)-N'-(4-methyl-3-thienyl)thiourea
is obtained analogously to the reaction described in example 1 b) from 4-
methyl-
3-thienyl isothiocyanate and 3,4,5,6-tetrafluoro-1,2-diaminobenzene.
Crystalline solid,
m.p.: 286-290 C.
10 b) 3N-(3,4,5,6-Tetrafluoro-2-benzimidazolyl)-4-methyl-3-thienylamine
hydrochloride
is obtained analogously to the procedure described in example 1 c) from N-(2-
amino-
3,4,5,6-tetrafluorophenyl)-N'-(4-methyl-3-thienyl)thiourea and methyl iodide.
Amorphous precipitate which crystallizes under ethyl acetate. Crystalline
solid,
15 m.p.225-228 C.
Example 8: 3N-(4-Methyl-2-benzimidazolyl)-4-methyl-3-thienylamine
hydrochloride
x HCI
S\
20 a) N-(2-Amino-3-methylphenyl)-N'-(4-methyl-3-thienyl)thiourea
is obtained analogously to the reaction described in example 1 b) from 4-
methyl-
3-thienyl isothiocyanate and 3-methyl- 1,2-diaminobenzene. Crystalline solid,
m.p.
184-186 C,
25 b) 3N-(4-Methyl-2-benzimidazolyl)-4-methyl-3-thienylamine hydrochloride
CA 02488242 2004-12-01
31
is obtained analogously to the procedure described in example 1 c) from N-(2-
amino-
3-m ethyl phenyl)-N'-(4-methyl-3-thienyl)thiourea and methyl iodide. Amorphous
precipitate which crystallizes under acetone. Crystalline solid, point of
decomposition:
320 C.
Example 9: trans-3N-(3a,4,5,6,7,7a-Hexahydro-1 H-2-benzimidazolyl)-4-methyl-
3-thienylamine hydrochloride (racemate)
xHC!
O:N
H
S
li
a) trans-N-(2-Aminocyclohexyl)-N'-(4-methyl-3-thienyl)thiourea (racemate)
is obtained analogously to the reaction described in example 1 b) from 4-
methyl-
3-thienyl isothiocyanate and racemic trans-l,2-diaminocyclohexane. Crystalline
solid,
m.p. 205-210 C,
b) trans-3N-(3a,4,5,6,7,7a-Hexahydro-1 H-2-benzimidazolyl)-4-methyl-
3-thienylamine hydrochloride (racemate)
0.6 g of racemic trans-N-(2-aminocyclohexyl)-N'-(4-methyl-3-thienyl)thiourea
is
suspended in 60 ml of toluene and dissolved by heating at 90 C. The mixture is
allowed to cool to 70 C, a solution of 0.376 g of dicyclohexylcarbodiimide in
5 ml of
anhydrous toluene is added dropwise and the mixture is stirred for a total of
about
10 hours at 70 C and for 2-3 days at room temperature. The crystalline solid
is filtered
off, the solvent is removed under reduced pressure using a rotary evaporator
and the
resulting oily residue is dissolved in a little ethyl acetate. Following
addition of an
anhydrous solution of hydrogen chloride in diethyl ether, a viscous
precipitate is
formed which, after addition of a little ethanol, crystallizes. Crystalline
solid,
m.p.: 261-264 C.
CA 02488242 2004-12-01
32
Example 10: trans-R,R-3N-(3a,4,5,6,7,7a-Hexahydro-1 H-2-benzimidazolyl)-
4-methyl-3-thienylamine hydrochloride
x HCI
S
\-N
H
a) trans- R,R-N-(2-Aminocyclohexyl)-N'-(4-methyl-3-thienyl)thiourea
is obtained analogously to the reaction described in example 1 b) from 4-
methyl-
3-thienyl isothiocyanate and trans-R,R-1,2-diaminocyclohexane by separation by
silica
gel column chromatography, eluting with a solvent mixture consisting of 10
parts of
ethyl acetate, 5 parts of n-heptane, 5 parts of methylene chloride, 5 parts of
methanol
and 1 part of 26% strength aqueous ammonia (hereinbelow referred to as
"mixture 4"),
as an amorphous oily product in addition to a crystalline product having a
higher
molecular weight of m.p. 94-100 C.
The amorphous product is processed further without further purification.
trans-R, R-N-(3a,4,5,6,7,7a-Hexahydro-1 H-2-benzimidazolyl)-4-methyl-3-
thienylamine
hydrochloride
is obtained analogously to the procedure described in example 1 c) by reacting
R,R-N-(2-aminocyclohexyl)-N'-(4-methyl-3-thienyl)thiourea and methyl iodide in
anhydrous ethanol as solvent and reaction medium. Amorphous precipitate which
is
chromatographed on silica gel using mixture 4 as mobile phase and crystallized
under
acetone. Crystalline solid, m.p. 235-238 C.
Example 11: trans-S,S-3N-(3a,4,5,6,7,7a-Hexahydro-1 H-2-benzimidazolyl)-
4-methyl-3-thienylamine hydrochloride
x HCI
\` H
N
S
CA 02488242 2004-12-01
33
a) trans- S,S-3N-(2-Am inocyclohexyl)-N'-(4-methyl-3-thienyl)thiourea
is obtained analogously to the reaction described in example 1 b) from 4-
methyl-
3-thienyl isothiocyanate and trans-S,S-1,2-diaminocyclohexane by separation by
silica
gel column chromatography using mixture 4 as mobile phase, as an amorphous
oily
product in addition to a product of higher molecular weight of m.p. 94-102 C.
The amorphous product is processed further without further purification.
b) trans-S,S-N-(3a,4,5,6,7,7a-Hexahydro-1 H-2-benzimidazolyl)-4-methyl-
3-thienylamine hydrochloride
is obtained analogously to the procedure described in example 1 c) by reacting
S,S-N-(2-aminocyclohexyl)-N'-(4-methyl-3-thienyl)thiourea and methyl iodide in
anhydrous ethanol as solvent and reaction medium. Amorphous precipitate which
is
chromatographed on silica gel using mixture 4 as mobile phase and crystallizes
under
acetone. Crystalline solid, m.p. 225-230 C.
.Example 12: 2-Chloro-3N-(2-benzimidazolyl)-4-methyl-3-thienylamine
hydrochloride
and 2,5-dichloro-3N-(2-benzimidazolyl)-4-methyl-3-thienylamine hydrochloride
x HCI x HCI
N NN
H H J \ CI
CI S CI S
are obtained analogously to the procedure described in example 2 from
3N-(2-benzimidazolyl)-4-methyl-3-thienylamine hydrochloride and N-
chlorosuccinimide
in glacial acetic acid. Column chromatography on silica gel using mixture 17
as mobile
phase results in the separation of 2,5-dichloro-3N-(2-benzimidazolyl)-4-methyl-
3-thienylamine hydrochloride (colorless crystalline compound, m.p.: 291 C)
from
2-chloro-3N-(2-benzimidazolyl)-4-methyl-3-thienylamine hydrochloride
(colorless
crystalline compound, m.p., 257-259 C).
CA 02488242 2004-12-01
34
Example 13: 2-Chloro-3N-(4-methyl-2-benzimidazolyl)-4-methyl-3-thienylamine
hydrochloride
x HCI
N
&
H
CI S
is obtained analogously to the procedure described in example 2 from 3N-(4-
methyl-
2-benzimidazolyl)-4-methyl-3-thienylamine hydrochloride and N-
chlorosuccinimide in
glacial acetic acid. Following column chromatography on silica gel using
mixture 17 as
mobile phase, 2-chloro-3N-(4-methyl-2-benzimidazolyl)-4-methyl-3-thienylamine
hydrochloride is obtained as a colorless to slightly yellowish crystalline
product.
M.p.255-259 C.
Example 14: 2-Chloro-3N-(4,5,6,7-tetrafluoro-2-benzimidazolyl)-4-methyl-
3-thienylamine hydrochloride
F xHCI
F N
1 \}-~
F # H /
F CI S
is obtained analogously to the procedure described in example 2: from
3N-(4,5,6,7-tetrafluoro-2-benzimidazolyl)-4-methyl-3-thienylamine
hydrochloride and
N-chlorosuccinimide in glacial acetic acid. Crystalline product. M.p. 233-235
C.
CA 02488242 2004-12-01
Example 15: trans-2-Chloro-3N-(3a,4,5,6,7,7a-hexahydro-1 H-2-benzimidazolyl)-
4-methyl-3-thienylamine hydrochloride (racemate)
x HCI
CI S
5 is obtained analogously to the procedure described in example 2: from
3N-(3a,4,5,6,7,7a-hexahydro-1 H-2-benzimidazolyl)-4-methyl-3-thienylamine
hydrochloride (racemate) and N-chlorosuccinimide in glacial acetic acid.
Crystalline
product. M.p. 258-260 C.
10 Example 16: trans-R,R-2-Chloro-3N-(3a,4,5,6,7,7a-hexahydro-1 H-2-benz-
imidazolyl)-4-methyl-3-thienylamine hydrochloride and trans- R,R-2,5-dichloro-
3N-(3a,4,5,6,7,7a-hexahydro-1 H-2-benzimidazolyi)-4-methyl-3-thienylamine
hydrochloride
x HCI HH x HCI
C:rN N
\ \ N
N t \ H CI
CI S CI S
15 are obtained analogously to the procedure described in example 2: from
trans-
R,R-3N-(3a,4,5,6,7,7a-hexahydro-1 H-2-benzimidazolyl)-4-methyl-3-thienylamine
hydrochloride and N-chlorosuccinimide in glacial acetic acid following
chromatographic.
separation of the two crystalline products in the following order:
a) trans-R,R-2,5-dichloro-3N-(3a,4,5,6,7,7a-hexahydro-1 H-2-benzimidazolyl)-
20 4-methyl-3-thienylamine hydrochloride, decomposition with foaming starting
at 80 C,
b) trans-R,R-2-chloro-3N-(3a,4,5,6,7,7a-hexahydro-1 H-2-benzimidazolyl)-
4-methyl-3-thienylamine hydrochloride, crystalline product. M.p. 260-262 C.
CA 02488242 2004-12-01
36
Example 17: trans-S,S-2-Chloro-3N-(3a,4,5,6,7,7a-hexahydro-1 H-2-benz-
imidazolyl)-4-methyl-3-thienylamine hydrochloride
x HCI
> H
N
CI S
is obtained analogously to the procedure described in example 2: from
trans-S,S-3N-(3a,4,5,6,7,7a-hexahydro-1 H-2-benzimidazolyl)-4-methyl-3-
thienylamine
hydrochloride and N-chlorosuccinimide in glacial acetic acid following
chromatographic
separation. Colorless crystalline product, m.p. 258-260 C.
Example 18: 2-Bromo-3N-(2-benzimidazolyl)-4-methyl-3-thienylamine
hydrochloride
and 2,5-dibromo-3N-(2-benzimidazolyl)-4-methyl-3-thienylamine hydrochloride
x HCI x HCI
(::CN
NN
H H ' \ Br
B S B S
are obtained analogously to the procedure described in example 2: from
3N-(2-benzimidazolyl)-4-methyl-3-thienylamine hydrochloride and N-
bromosuccinimide
(instead of N-chlorosuccinimide) in glacial acetic acid. Following. column
chromatography on silica gel using a mixture of 5 parts of dichloromethane, 3
parts of
n-heptane, 1 part of glacial acetic acid and 1 part of ethanol (hereinbelow
referred to
as "mixture 1") as mobile phase and treatment with a solution of hydrogen
chloride gas
in ether, 2-bromo-3N-(2-benzimidazolyl)-4-methyl-3-thienylamine hydrochloride,
a
crystalline product of m.p. 228-231 C, and 2,5-dibromo-3N-(2-benzimidazolyl)-
4-methyl-3-thienylamine hydrochloride, a crystalline product of m.p. 208-210
C, are
obtained by fractional crystallization in ethyl acetate.
CA 02488242 2004-12-01
37
Example 19: trans- R,R-2-Bromo-3N-(3a,4,5,6,7,7a-hexahydro-1 H-2-benz-
imidazolyl)-4-methyl-3-thienylamine hydrochloride and trans- R,R-2,5-dibromo-
3N-(3a,4,5,6,7,7a-hexahydro-1 H-2-benzimidazolyl)-4-methyl-3-thienylamine
hydrochloride
x HCI x HCI
H
N>--N
H f \ 1 Br
B S B S
are obtained analogously to the procedure described in example 19: from
trans- R,R-3N-(3a,4,5,6,7,7a-hexahydro-1 H-2-benzimidazolyl)-4-methyl-3-
thienylamine
hydrochloride and N-bromosuccinimide in glacial acetic acid. Following column
chromatography on silica gel using mixture 1 as mobile phase, and treatment
with a
solution of hydrogen chloride gas in ether, trans-R,R-2-bromo-
3N-(3a,4,5,6,7,7a-hexahydro-1 H-2-benzimidazolyl)-4-methyl-3-thienylamine
hydrochloride, crystalline product, m.p. 215-218 C and trans-R,R-2,5-dibromo-
3N-(3a,4,5,6,7,7a-hexahydro-1 H-2-benzimidazolyl)-4-methyl-3-thienylamine
hydrochloride, crystalline product, m.p. 218-220 C are obtained following
fractional
crystallization in ethyl acetate.
Example 20: 3N-(4-Chloro-2-benzimidazolylamino)-4-methylthiophene
hydrochloride
CI x HCI
6 N H
H l~
S
a) N-(2-Amino-3-chlorophenyl)-N'-(4-methyl-3-thienyl)thiourea
is obtained analogously to the reaction described in example 1 b) from 4-
methyl-3-
thienyl isothiocyanate and 3-chloro-1,2-diaminobenzene (prepared by catalytic
hydrogenation of 3-chloro-2-nitroaniline using Pt on activated carbon under
atmospheric pressure at room temperature). Crystalline solid, m.p. 298-305 C,
CA 02488242 2004-12-01
38
b) 3N-(4-Chloro-2-benzimidazolylamino)-4-methylthiophene hydrochloride
is obtained analogously to the procedure described in example 1 c) from N-(2-
amino-3-
chlorophenyl)-N`-(4-methyl-3-thienyl)-thiourea and methyl iodide. Amorphous
precipitate which crystallizes under ethyl acetate. Crystalline solid, point
of
decomposition 240-245 C
Example 21: 2-Chloro-3N-(4-chloro-2-benzimidazolylamino)-4-methylthiophene
hydrochloride
CI x HCI
H
N>-N
H
CI S
is obtained analogously to the procedure described in example 2 from 3N-(4-
chloro-2-
benzimidazolyl)-4-methyl-3-thienylamine hydrochloride and N-chlorosuccinimide
in
glacial acetic acid. Following silica gel column chromatography using a
mixture of 10
parts of methylene chloride and 1 part of methanol as mobile phase, 2-chloro-
3N-
(4-chloro-2-benzimidazolylamino)-4-methylthiophene hydrochloride is, after
crystallization under ethyl acetate, obtained as a colorless to slightly
yellowish solid.
M.p. 270-272 C.
Example 22: 2-Bromo-3N-(4-chloro-2-benzimidazolylamino)-4-methylthiophene
hydrochloride
CI x HCI
N}-N
H l~
Br S
is obtained analogously to the procedure described in example 2 from 3N-(4-
chloro-
2-benzimidazolylamino)-4-methylthiophene hydrochloride and N-bromosuccinimide
(instead of N-chlorosuccinimide) in glacial acetic acid. Following silica gel
column
chromatography using a mixture of 20 parts of ethyl acetate, 10 parts of n-
heptane and
CA 02488242 2004-12-01
39
3 parts of glacial acetic acid as mobile phase and treatment with a solution
of hydrogen
chloride gas in ether, 2-bromo-3N-(4-chloro-2-benzimidazolylamino)-4-
methyithiophene hydrochloride is obtained by fractionated crystallization in
ethyl
acetate in the presence of hydrogen-chloride-saturated ether. Crystalline
product of
m.p.278-280 C
Example 23: (2-Bromo-4-methyithiophene-3-yl)-(5-fuoro-1 H-benzoimidazol-2-
yl)amine
F N H x HCI
\-- N
N /
S
hydrochloride Br
(5-Fluoro-1 H-benzimidazol-2-yl)-(4-methylthiophene-3-yl)amine (300 mg)
(example 1)
was dissolved in glacial acetic acid (50 ml). At room temperature, N-
bromosuccinimide
(207 mg) dissolved in glacial acetic acid (10 ml), was slowly added dropwise,
with
vigorous stirring. After the addition had ended, stirring was continued for
another
10 min and the glacial acetic acid was then distilled off under reduced
pressure, and
the residue was dissolved in ethyl acetate and washed with saturated potassium
carbonate solution. The organic phase was dried over magnesium sulfate,
filtered and
concentrated. The residue was purified by preparative chromatography and the
product-containing fractions were combined, freed from acetonitrile, made
basic and
extracted three times with ethyl acetate. The organic phases were combined,
dried
(MgSO4) and filtered. Following removal of the solvent under reduced pressure,
water
and 2N hydrochloric acid were added to the residue and the mixture was freeze-
dried.
This gave 245 mg of the desired product.
LCMS-Rt (B): 0.95 min
MS (ES+, M+H+): 326.09
CA 02488242 2004-12-01
Example 24: 2-Bromo-3N-(4-fluoro-2-benzimidazolylamino)-4-methylthiophene
hydrochloride and 2,5-dibromo-3N-(4-fluoro-2-benzimidazolylamino)-4-methyl-
thiophene hydrochloride
F xHCI F xHCI
~~--N I N> N
/ and /
H H Sr
Br S Br S
5
A solution of 0.161 g of N-bromosuccinimide in 6 ml of glacial acetic acid is
added to a
solution of 0.214 g of 3N-(4-fluoro-2-benzimidazolylamino)-4-methylthiophene
hydrochloride in 6 ml of glacial acetic acid, and the mixture is stirred at
room
temperature for 30 minutes. After removal of the solvent by distillation,
water is added
10 to the residue and the mixture is made alkaline using 2N NaOH and extracted
with
ethyl acetate. The organic phase is dried, the solvent is distilled off and
the residue is
separated by silica gel column chromatography using a mixture of 20 parts of
ethyl
acetate, 10 parts of n-heptane and 3 parts of glacial acetic acid. The
hydrochlorides of
the two compounds are obtained by distilling off the fractionated solutions,
dissolving
15 the residue in ethyl acetate and precipitating the product by addition of
hydrogen-
chloride-saturated diethyl ether. Crystallization was promoted by gentle
warming.
Example 24a: 2-Bromo-3N-(4-fluoro-2-benzimidazolylamino)-4-methylthiophene
hydrochloride: colorless crystals; m.p. 212 C (decomposition).
Example 24b: 2,5-Dibromo-3N-(4-fluoro-2-benzimidazolylamino)-4-methylthiophene
20 hydrochloride: colorless crystals; m.p. 242-244 C (decomposition).
Example 25: 3N-(5-Methoxy-2-benzimidazolylamino)-4-methylthiophene
H3C-O N H
\>- N
H ZI\
S
25 a) N-(2-Amino-4-methoxyphenyl)-N`-(4-methyl-3-thienyl)thiourea
A mixture of 5.89 g of 4-methylthiophene 3-isothiocyanate and 5 g of 4-methoxy-
1,2-diaminobenzene in 60 ml of anhydrous THE is stirred at room temperature
for
CA 02488242 2004-12-01
41
2 hours, and the solvent is distilled off. Water is added to the residue, the
mixture is
extracted with ethyl acetate, the dark solution is treated with activated
carbon and the
organic solvent is re-evaporated. With gentle warming, the residue is treated
repeatedly with diisopropyl ether and the solid is filtered off. Brown
crystalline solid,
m.p.143-146 C.
b) A mixture of 2.83 g of N-(2-amino-4-methoxyphenyl)-N`-(4-methyl-3-
thienyl)thiourea,
8.5 g of methyl iodide , and 100 ml of anhydrous ethanol is boiled under ref
lux for
5 hours, and the solvent is then distilled off and water is added to the
residue. Using
2N aqueous sodium hydroxide solution, the mixture is made alkaline and then
extracted with ethyl acetate, the organic phase is treated with water and then
with
activated carbon and the product is purified by silica gel column
chromatography using
a mobile phase mixture of 20 parts of ethyl acetate, 10 parts of n-heptane and
3 parts
of glacial acetic acid. This gives 3N-(5-methoxy-2-benzimidazolylamino)-4-
methylthiophene as an amorphous product.
Example 26: 3N-(5-Methoxy-2-benzimidazolylamino)-4-methylthiophene
hydrochloride
x HCI
H3C-O \~H
N
H
ts\
is obtained by precipitating a solution of 0.2 g of 3N-(5-methoxy-2-
benzimidazolyl-
amino)-4-methylthiophene (example 25) in 10 ml of ethyl acetate using a
saturated
solution of hydrogen chloride gas and diethyl ether, giving a crystalline
precipitate.
M.p.: 222-225 C
CA 02488242 2004-12-01
42
Example 27: 2-Chloro-3N-(5-methoxy-2-benzimidazolylamino)-4-methylthiophene
hydrochloride
x HCI
H3C-O I N>_H
N
H
CI S
For about 2 to 21/2 hours, a mixture of 0.519 g of 3N-(5-methoxy-2-
benzimidazolyl-
amino)-4-methylthiophene hydrochloride, 0.046g of N-chlorosuccinimide and 10-
15 ml
of glacial acetic acid is heated at 45 C. The glacial acetic acid is then
distilled off,
water is added to the residue and the mixture is adjusted to pH 9-10 using 2N
NaOH.
The mixture is extracted with ethyl acetate, the solvent is evaporated and the
residue
is chromatographed on silica gel on a medium-pressure column using a mixture
of
parts of ethyl acetate, 10 parts of n-heptane and 3 parts of glacial acetic
acid. The
base obtained after removal of the solvent by distillation is, in ethyl
acetate, converted
into the hydrochloride using saturated etheral hydrogen chloride solution, and
the
product is crystallized under ethyl acetate. Crystalline solid m.p.: 182-186
C.
Example 28: 2,5-Dichloro-3N-(5-methoxy-2-benzimidazolylamino)-4-
methylthiophene
hydrochloride
x HCI
H3C-O ,N H
N
N
H CI
CI S
Analogous work-up of a reaction mixture of 3N-(5-methoxy-2-
benzimidazolylamino)-4-
methylthiophene hydrochloride, N-chlorosuccinimide and glacial acetic acid for
about 2
to 2'/2 hours at 55 C gave 2,5-dichloro-3N-(5-methoxy-2-benzimidazolylamino)-
4-methylthiophene. Crystalline solid, m.p.: 278-282 C.
CA 02488242 2004-12-01
43
Example 29: 3N-(4-Methoxy-2-benzimidazolylamino)-4-methylthiophene
hydrochloride
H3c,0 x HCI
N>-H
~ N
H
S
a) 3-Methoxy- 1,2-diaminobenzene
was obtained as a brown oil by hydrogenation of 2-methoxy-6-nitroaniline using
hydrogen gas and Raney nickel as catalyst at room temperature and a pressure
of
3 bar. The product was converted into the thiourea without further
purification.
b) N-(2-Amino-3-methoxyphenyl)-N'-(4-methyl-3-thienyl)thiourea
is obtained analogously to the procedure described in example 25 a) from 3-
methoxy-
1,2-diaminobenzene and 4-methyl-3-thienyl isothiocyanate in anhydrous THF,
followed
by medium-pressure chromatography on silica gel using a mixture of 1 part of
toluene
and 1 part of ethyl acetate. Crystalline solid, m.p.: 148-153 C.
Solidification of the melt
and next m.p. at 260 C.
C) 3N-(4-Methoxy-2-benzimidazolylamino)-4-methylthiophene hydrochloride
is obtained analogously to the procedures described in examples 25 and 26 from
N-(2-amino-3-methoxyphenyl)-N'-(4-methyl-3-thienyl)thiourea by heating with
methyl
iodide in THE, analogous work-up and treatment of the benzimidazole with HCI
in
ether.
Crystalline solid, m.p.: 230-235 C.
Example 30: 2-Chloro-3N-(4-methoxy-2-benzimidazolylamino)-4-methylthiophene
hydrochloride
H3C,0 x HCI
N H
\>-
H
CI S
CA 02488242 2004-12-01
44
A mixture of 0.1 g of 3N-(4-methoxy-2-benzimidazolylamino)-4-methylthiophene
hydrochloride, 0.046 g of N-chlorosuccinimide and 10-15 ml of glacial acetic
acid is
heated at 40 C for about 2 to 21/2 hours. The glacial acetic acid is then
distilled off,
water is added to the residue and the pH is adjusted to 9-10 using 2N NaOH.
The
mixture is extracted with ethyl acetate, the solvent is evaporated and the
residue is
chromatographed on silica gel on a medium-pressure column using a mixture of
20 parts of ethyl acetate, 10 parts of n-heptane and 3 parts of glacial acetic
acid. The
resulting base is, in ethyl acetate, converted into the hydrochloride using
saturated
etheral hydrogen chloride solution. Colorless to light-yellow crystalline
solid, m.p.:
248-250 C.
Example 31: 3N-(4-Chloro-6-trifluoromethyl-2-benzimidazolylamino)-4-methyl-
thiophene hydrochloride
CI x HCI
N>-H
N
CN
F3C
s
a) N-(2-Amino-3-chloro-5-trifluoromethylphenyl)-N'-(4-methyl-3-
thienyl)thiourea
is obtained analogously to the procedure described in example 25 a) by
reacting
3-chloro-5-trifluoromethyl-1,2-diaminobenzene and 4-methyl-3-thienyl
isothiocyanate in
anhydrous THE at room temperature for 3 days. The solvent is distilled off and
water is
added to the residue, and the mixture is then extracted with ethyl acetate,
the solvent
is again distilled off and the amorphous residue is crystallized under
diisopropyl ether.
M.p.: > 310 C.
b) 3N-(4-chloro-6-trifluoromethyl-2-benzimidazolylamino)-4-methylthiophene
hydrochloride
is obtained analogously to the procedures described under examples 25 and 26
from
N-(2-amino-3-chloro-5-trifluoromethylphenyl)-N'-(4-methyl-3-thienyl)thiourea
by boiling
with methyl iodide in THE under reflux conditions for 5 hours, analogous work-
up and
purification by medium-pressure silica gel column chromatography using a
mixture of
identical parts by volume of ethyl acetate and toluene. The solvent is
evaporated and
CA 02488242 2004-12-01
the residue is then dissolved in ethyl acetate, giving, by addition of a
saturated solution
of hydrogen chloride in diethyl ether, 3N-(4-chloro-6-trifluoromethyl-2-
benzimidazolyl-
amino)-4-methylthiophene hydrochloride as a crystalline precipitate. Solid,
m.p.: 210-
213 C.
5
Example 32: 2-Chloro-3N-(4-chloro-6-trifluoromethyl-2-benzimidazolylamino)-
4-methylthiophene hydrochloride
CI x HCI
N>-H
N
FC N
CI S
A mixture of 0.34 g of 3N-(4-methoxy-2-benzimidazolylamino)-4-methylthiophene
10 hydrochloride, 0.151 g of N-chlorosuccinimide and 20 ml of glacial acetic
acid is stirred
at room temperature for 1/2 hour and heated at 60 C for one hour. The glacial
acetic
acid is then distilled off, water is added to the residue and the pH is
adjusted to 9-10
using 2N NaOH. The mixture is extracted with ethyl acetate, the solvent is
evaporated
and the residue is chromatographed on silica gel on a medium-pressure column
using
15 a mixture of identical parts of toluene and ethyl acetate. The solvent is
distilled off and
the resulting base is then, in ethyl acetate, converted into the hydrochloride
using
saturated etheral hydrogen chloride solution,. Colorless to light-yellow
crystalline solid.
mp.: 247-250 C.
20 Example 33: 3N-(4-Carboxy-2-benzimidazolylamino)-4-methylthiophene
hydrochloride
6 OOH x HCI
N~H
N
H
S
a) N-(2-Amino-3-carboxyphenyl)-N'-(4-methyl-3-thienyl)thiourea
is obtained analogously to the procedure described in example 25 a) from 3-
carboxy-
1,2-diaminobenzene and 4-methyl-3-thienyl isothiocyanate in anhydrous THF,
followed
25 by medium-pressure chromatography on silica gel using a mixture of 12 parts
of
methylene chloride and 1 part of methanol. Amorphous product.
CA 02488242 2004-12-01
46
b) 3N-(4-Carboxy-2-benzimidazolylamino)-4-methylthiophene hydrochloride
is obtained by boiling a solution of 1.12 g of N-(2-amino-3-carboxyphenyl)-
N'-(4-methyl-3-thienyl)thiourea and 3.1 g of methyl iodide in 60 ml of ethanol
under
reflux. The solvent is evaporated, water is added to the residue, the pH is
adjusted to 5
using 2N aqueous HCI and the precipitate is filtered off. Crystalline solid,
point of
decomposition: 265-285 C.
Example 34: 2-Chloro-3N-(4-carboxy-2-benzimidazolylamino)-4-methylthiophene
hydrochloride
x HCI
N>-H
(5N
N CI
s
is obtained analogously to the procedure described in example 32 from 0.2 g of
3N-
(4-carboxy-2-benzimidazolylamino)-4-methylthiophene hydrochloride and 0.103 g
of
N-chlorosuccinimide in 20-25 ml of glacial acetic acid and precipitation of
the
corresponding hydrochloride using HCI-saturated diethyl ether in ethyl acetate
and
subsequent crystallization under diisopropyl ether and ethyl acetate. Point of
decomposition 170 C.
Example 35: 3N-[4-(1-Pipe ridinocarbonyl)-2-benzimidazolylamino]-4-
methylthiophene
hydrochloride
N 0
x HCI
1 \ H
S
N~N 1
H
0.215g of N,N'-carbonyldiimidazole is added to a mixture of 0.330 g of 3N-(4-
carboxy-
2-benzimidazolylamino)-4-methylthiophene hydrochloride, 30 ml of anhydrous THE
and 5 ml of anhydrous dimethylacetamide. The mixture is stirred at room
temperature
CA 02488242 2004-12-01
47
for about 4 hours, when the evolution of carbon dioxide has ceased, and 0.411
g of
piperidine is then added. The solution is stirred at room temperature for 2
hours and,
after standing overnight, the solvent is distilled off under reduced pressure.
The
residue is triturated with water, the solid is filtered off and dissolved in
ethyl acetate,
the insoluble fraction is removed by filtration and the solvent is distilled
off under
reduced pressure. Foam-like amorphous product.
Example 36: 2-Chloro-4-methyl-3N-[4-(1-piperidinocarbonyl)-2-
benzimidazolylamino]-
thiophene hydrochloride
N 0
x HCI
N>-H
N
H
CI S
A mixture of 0.2 g of 3N-[4-(1-piperidinocarbonyl)-2-benzimidazolylamino]-4-
methyl-
thiophene hydrochloride and 0.086g of N-chlorosuccinimide in about 20 ml of
glacial
acetic acid is stirred at room temperature for 11/2 hours and at 35 C for
about 30 min,
the solvent is distilled off and the residue is, after addition of water, made
alkaline
using 2N NaOH. Following extraction with ethyl acetate, the solvent is
evaporated and
the residue is purified by medium-pressure silica gel column chromatography
using a
mixture of 20 parts of ethyl acetate, 10 parts of n-heptane and 3 parts of
glacial acetic
acid. The solvent is distilled off, the residue is dissolved in ethyl acetate
and the
mixture is acidified using a solution of ether saturated with hydrogen
chloride. The
amorphous residue is crystallized under a mixture of ethyl acetate with a
little acetone
and a little ethanol. Amorphous solid, point of decomposition from 100 C.
CA 02488242 2004-12-01
48
Example 37: 2-Chloro-3N-(4-fluoro-2-benzimidazolylamino)-4-methylthiophene
hydrochloride
F x HCI
H
N\>-N
H
I
CI S
0.132 g of N-chlorosuccinimide is added to 0.234 g of 3N-(4-fluoro-2-
benzimidazolyl-
amino)-4-methylthiophene hydrochloride in about 20 ml of glacial acetic acid
and the
mixture is stirred at room temperature for 30 minutes and at 50-60 C for
another
11/2 hours. The acetic acid is distilled off under reduced pressure, water is
then added
to the residue and the pH is adjusted to about 10-11 using 2N NaOH, and the
mixture
is extracted with ethyl acetate, which is then distilled off. The residue is
chromatographed on a silica gel column under medium-pressure conditions using
a
mixture of 20 parts of ethyl acetate, 10. parts of n-heptane and 3 parts of
glacial acetic
acid. After concentration, the residue is dissolved in a little ethyl acetate
and the
hydrochloride is precipitated by addition of hydrogen-chloride-saturated
diethyl ether.
Colorless to light-yellow crystalline solid. M.p.: 268--270 C.
Example 38: 2-Chloro-3N-(4-hydroxy-2-benzimidazolylamino)-4-methylthiophene
hydrochloride
H x HCI
N H
H
CI S
A suspension of 0.13 g of 2-chloro-3N-(4-methoxy-2-benzimidazolylamino)-4-
methyl-
thiophene hydrochloride in about 20 ml of anhydrous methylene chloride is
added to a
suspension of 0.29 g of activated anhydrous aluminum chloride in 10 ml of
anhydrous
methylene chloride, and the reaction mixture is stirred at 55 C for 2 hours.
After
cooling, the reaction mixture is poured into ice-water and extracted with
ethyl acetate,
the organic phase is dried over sodium sulfate and the solvent is distilled
off. The
CA 02488242 2004-12-01
49
residue is chromatographed on a silica gel column under medium-pressure
conditions
using a mixture of 20 parts of ethyl acetate, 10 parts of n-heptane and 3
parts of glacial
acetic acid, and the eluate is concentrated under reduced pressure. The
residue is
dissolved in ethyl acetate and the hydrochloride is precipitated by addition
of
hydrogen-chloride-saturated diethyl ether. Crystalline solid. M.p. 246-248 C.
Example 39: 2-Chloro-3N-(2-benzimidazolylamino)-4-methylthiophene
N H
\>--N
H
C S
is obtained by adding 2N NaOH to a solution of 3 g of 2-chloro-3N-(2-
benzimidazolyl-
amino)-4-methylthiophene hydrochloride in 200 ml of water until a pH of 10 is
set. The
crystals are filtered off and washed repeatedly with water. Yield: 2.52 g.
Colorless
crystal powder. M.p. 182-185 C.
Example 40: 2-Chloro-3N-(2-benzimidazolylamino)-4-methylthiophene hydrobromide
x HBr
~ N H
~>- N
H
CI S
0.25 g of 2-chloro-3N-(2-benzimidazolylamino)-4-methylthiophene is dissolved
in 10 ml
of ethanol, 0.1 ml of 48% strength HBr is then added and the mixture is
stirred at room
temperature for a little while. The solvent is distilled off and the residue
is crystallized
under ethyl acetate. Yield: 0.29 g. Colorless crystals, point of
decomposition:
252-254 C.
CA 02488242 2004-12-01
Example 41: 2-Chloro-3N-(2-benzimidazolylamino)-4-methylthiophene adipic acid
salt
CN
\}-N X HOOC COON
H ' \
CI S
is obtained analogously to the procedure described in example 40 from 2-chloro-
3N-
(2-benzimidazolylamino)-4-methylthiophene using one equivalent of adipic acid.
5 Colorless crystals. M.p. 155-157 C.
Example 42: 2-Chloro-3N-(2-benzimidazolylamino)-4-methylthiophene oxalic acid
salt
CN
>--N X HOOC ~COOH
H
CI S
10 is obtained analogously to the procedure described in example 40 by
reacting
2-chloro-3N-(2-benzimidazolylamino)-4-methylthiophene with one equivalent of
oxalic
acid in ethyl acetate. Colorless crystals. M.p.: 220-222 C.
Example 43: 2-Chloro-3N-(2-benzimidazolylamino)-4-methylthiophene phosphoric
acid
15 salt
CN>_H
N
N x H3PO4
CI S
is obtained analogously to the procedure described in example 40 from 2-chloro-
3N-
(2-benzimidazolylamino)-4-methylthiophene using one equivalent of phosphoric
acid.
Colorless crystals. Decomposition range: 113-175 C.
Example 44: (1 H-Benzimidazol-2-yl)-(2-chloro-4-methylthiophen-3-
yl)methylamine
N
C~N N
H
6S
CI
CA 02488242 2004-12-01
51
Finely powdered dry potassium carbonate (66 mg) was added to a solution of 2-
chloro-
3N-(2-benzimidazolyl)-4-methyl-3-thienylamine (125 mg, from example 39) and
dry
methanol (20 ml). Methyl iodide (74 mg) was then added dropwise with exclusion
of
moisture and vigorous stirring, and the mixture was kept under reflux for
three days.
The solvent was removed under reduced pressure and the residue was then
partitioned between ethyl acetate and water, the ethyl acetate phase was dried
with
magnesium sulfate, the magnesium sulfate was filtered off and the filtrate was
evaporated to dryness. The product was then purified by preparative HPLC. The
product-containing fractions were combined and, after removing the
acetonitrile under
reduced pressure, freeze-dried. For further purification, the product was
finally
chromatographed on silica gel using ethyl acetate/heptane (1/4). The product-
containing fractions were combined and then evaporated to dryness, and the
residue
was taken up in HCI and freeze-dried. This gave 5 mg of a solid.
LCMS-Rt (A): 2.04 min
MS (ES+, =M+H+): 278.05
Example 45: (5,6-Difluoro-1 H-benzimidazol-2-yl)-(4-methylthiophen-3-yl)amine
trifluoroacetic acid salt
F I N~H x CF3-COOH
N
F / N
H
S
3-Isothiocyanato-4-methylthiophene (1.08 g), dissolved in absolute
tetrahydrofuran
(30 ml), was added dropwise to a solution of 1,2-diamino-4,5-difluorobenzene
(1 g) in
absolute tetrahydrofuran (20 ml). The mixture was then stirred at room
temperature for
2 hours and allowed to stand overnight. Methyl iodide (0.44 ml) was added and
the
mixture was then stirred for 8 hours and allowed to stand overnight. The
tetrahydro-
furan was then removed under reduced pressure, the residue was partitioned
between
ethyl acetate and water, the phases were separated and the ethyl acetate phase
was
dried over magnesium sulfate. The residue was absorbed under silica gel and
chromatographed on silica gel using the mobile phase n-heptane : ethyl acetate
= 1:1.
CA 02488242 2004-12-01
52
This gave 229 mg of the desired compound as the free base.
An impure fraction from the above chromatography was purified by preparative
HPLC.
Following freeze-drying, 42.2 mg of the desired compound were isolated as
trifluoroacetic acid salt.
LCMS-Rt (A): 1.98 min
MS (ES+, M+H+): 266.13
Example 46: (2-Chloro-4-methylthiophen-3-yl)-(5,6-difluoro-1 H-benzoimidazol-
2-yl)amine hydrochloride
F N x HCI
F N
S
At room temperature, a solution of N-chlorosuccinimide (124.6 mg) in glacial
acetic
acid (5 ml) was added dropwise to a solution of (5,6-difluoro-1 H-benzimidazol-
2-yl)-(4-
methylthiophen-3-yl)amine (225 mg) in glacial acetic acid (5 ml). The mixture
was then
stirred at room temperature for 3.5 hours. The glacial acetic acid was then
removed
and the residue was taken up in water and adjusted to pH 10 using 2 M aqueous
sodium hydroxide solution. The aqueous phase was extracted three times with
ethyl
acetate, the combined organic phases were dried over magnesium sulfate and the
solvent was removed. The residue was purified by preparative chromatography
and.
the product-containing fractions were combined, freed from acetonitrile, made
basic
and extracted three times with ethyl acetate. The organic phases were
combined, dried
(MgSO4), filtered and concentrated. The residue was taken up in water,
acidified with
10% strength hydrochloric acid and freeze-dried. This gave 81 mg of the
desired
product as a solid.
LCMS-Rt (A): 2.15 min
MS (ES+, M+H+): 300.11
CA 02488242 2004-12-01
53
Example 47: (2-Bromo-4-methylthiophen-3-yl)-(5,6-difluoro-1 H-benzoimidazol-2-
yl)-
amine
H
F \ N
/ />--N
F N / 1
Br S
At room temperature, a solution of N-bromosuccinimide (8 mg) in glacial acetic
acid
(0.5 ml) was added dropwise to a solution of (5,6-difluoro-1 H-benzimidazol-2-
yl)-
(4-methylthiophen-3-yl)amine trifluoroacetic acid salt (15 mg, example 45) in
glacial
acetic acid (0.5 ml) in a ReactiVial, and the mixture was stirred at room
temperature for
0.5 h. The acetic acid was then removed under reduced pressure and saturated
potassium carbonate solution and ethyl acetate were added to the residue. The
organic phase was removed and the aqueous phase was then extracted twice with
ethyl acetate. The combined organic phases were dried using magnesium sulfate
and
the drying agent was then filtered off. The residue that remained after
removal of the
solvent under reduced pressure was purified by preparative chromatography. The
product-containing fractions were combined and freed from acetonitrile,
saturated
sodium bicarbonate solution was added to the residue and the mixture was
extracted
three times with ethyl acetate. The organic phases were combined, dried
(MgSO4) and
filtered. After removal of the ethyl acetate under reduced pressure, the
residue was
coevaporated with toluene and then dried under high vacuum. This gave 8.1 mg
of the
desired compound.
LCMS-Rt (D): 1.45 min
MS (ES+, M+H+): 343.96
CA 02488242 2004-12-01
54
Example 48: [(2-Chioro-4-methylthiophen-3-yl)-(4,5,6,7-tetrahydro-1 H-
benzimidazol-2-
yl)]amine hydrochloride
a) 1,4-Dioxaspiro[4.5]dec-6-ylamine
H2N
O O
\-j
The amine required as precursor was prepared in accordance with G131 131191.
2-Chlorocyclohexanone was reacted with phthalimide to give 2-(2-oxocyclo-
hexyl)isoindole-1,3-dione, which was ketalized with ethylene glycol in the
presence of
para-toluenesulfonic acid, giving 2-(1,4-dioxaspiro[4.5]dec-6-yl)isoindole-1,3-
dione.
Treatment with hydrazine hydrate to remove the phthalimideradical gave the
desired
1,4-dioxaspiro[4.5]dec-6-ylamine.
b) 1-(1,4-Dioxaspiro[4.5]dec-6-yl)-3-(4-methylthiophen-3-yl)thiourea
S
S
N --Ik N
H H O O
A solution of 3-isothiocyanato-4-methylthiophene (296.2 mg, see example 1 a)
in
absolute tetrahydrofuran (10 ml) was added dropwise to a solution of 1,4-dioxa-
spiro[4.5]dec-6-ylamine (300 mg) in absolute tetrahydrofuran (10 ml), the
mixture was
stirred at room temperature for 2 hours and the solvent was then removed under
reduced pressure. The residue was purified by preparative chromatography and
the
product-containing fractions were combined, freed from acetonitrile, made
basic and
extracted three times with ethyl acetate. The organic phases were combined,
dried
(MgSO4) and filtered. This gave 428 mg of the desired product.
LCMS-Rt (A): 3.57 min
MS (ES+, M+H+): 313.19
CA 02488242 2004-12-01
c) 1-(1,4-Dioxaspiro[4.5]dec-6-yl)-2-methyl-3-(4-methylthiophen-3-
yl)isothiourea
S
S N;`
H p0
1-(1,4-Dioxaspiro[4.5]dec-6-yl)-3-(4-methylthiophen-3-yl)thiourea (393 mg) was
dissolved in absolute tetrahydrofuran (8.5 ml), and a solution of methyl
iodide (179 mg)
5 in absolute tetrahydrofuran (0.5 ml) was added. The mixture was then stirred
at 70 C
in sand bath for 2 days. Ethyl acetate was then added to the reaction mixture,
and the
mixture was washed twice with water. The organic phase was dried over
magnesium
sulfate and the solvent was removed after filtration. The residue was purified
by
preparative chromatography and the product-containing fractions were combined,
10 freed from acetonitrile, made basic and extracted three times with ethyl
acetate. The
organic phases were combined, dried (MgSO4) and filtered. This gave 59 mg of
the
desired product which was used directly for the next step.
LCMS-Rt (C): 1.05 min
MS (ES+, M+H+): 327.4
d) N-(1,4-Dioxaspiro[4.5]dec-6-yl)-N'-(4-methylthiophen-3-yl)guanidine
S NH
N N
H p
In a ReactiVial, a 7 M solution of ammonia in methanol (2 ml) was added to 1-
(1,4-dioxaspiro[4.5]dec-6-yl)-2-methyl-3-(4-methylthiophen-3-yl)isothiourea
(58.8 mg),
and the mixture was heated in a sand bath at about 100 C for 16 hours. Removal
of
the solvent gave a residue of 51 mg of an oily product which was directly
reacted
further.
LCMS-Rt (C): 1.00 min
MS (ES+, M+H+): 296.4
CA 02488242 2004-12-01
56
e) N-(2-Chloro-4-methylthiophen-3-yl)-N'-(1,4-dioxaspiro[4.5]dec-6-
yl)guanidine
S NH
i
N N
Cl ~-Q
H O O
U
N-(1,4-Dioxaspiro[4.5]dec-6-yl)-N'-(4-methylthiophen-3-yl)guanidine (49 mg)
was
dissolved in glacial acetic acid (3 ml), and a solution of N-chlorosuccinimide
(20.3 mg)
in glacial acetic acid (5 ml) was added slowly. The mixture was stirred for a
number of
hours and then allowed to stand at room temperature over the weekend, after
which
the glacial acetic acid was removed under reduced pressure, the residue was
taken up
in water and the mixture was adjusted to pH 10 using 2N sodium hydroxide
solution.
The basic phase was extracted three times with ethyl acetate and the combined
organic phases were dried over magnesium sulfate, filtered and concentrated.
The
residue was purified by preparative chromatography and the product-containing
fractions were combined, freed from acetonitrile, made basic and extracted
three times
with ethyl acetate. The organic phases were combined, dried (MgSO4) and
filtered.
Removal of the solvent under reduced pressure gave 24 mg of the desired
product
which was used directly for the next step.
LCMS-Rt (C): 1.09 min
MS (ES+, M+H+): 330.4
f) ((2-Chloro-4-methylthiophen-3-yl)-(4,5,6,7-tetrahydro-1 H-benzoimidazol-2-
yl))amine
hydrochloride
S
N
CI H H HCI
N-(2-Chloro-4-methylthiophen-3-yl)-N'-(1,4-dioxaspiro[4.5]dec-6-yl)guanidine
(24 mg)
was dissolved in 2N hydrochloric acid (1 ml) and stirred at room temperature
for
30 min. Concentrated hydrochloric acid (1 ml) was then added, and the mixture
was
CA 02488242 2004-12-01
57
stirred for another two hours. The mixture was then diluted with a little
water and
freeze-dried. Toluene was added to the residue and then distilled off under
reduced
pressure. This step was repeated twice, giving 22 mg of the desired product as
a solid.
LCMS-Rt (B): 0.95 min
MS (ES+, M+H+): 268.07
Example 49: 2-Chloro-3N-(2-benzimidazolylamino)-4-methylthiophene
benzenesulfonate
HOB
OS
~-- N
H
CI S
2-Chloro-3N-(2-benzimidazolylamino)-4-methylthiophene (250 mg) was dissolved
in
THE (5 ml), and benzenesulfonic acid (150 mg), dissolved in THE (5 ml), was
added
with stirring. After 3 h, the reaction mixture was left in the fridge
overnight. The
precipitate was filtered off with suction and dried at 75 C under high vacuum,
giving
the desired product. Colorless crystals. M.p.: 235 C
Example 50: 2-Chloro-3N-(2-benzimidazolylamino)-4-methylthiophene methane-
sulfonate
o j
N H HO \
N
H
H
CI S
was obtained analogously to the procedure described in example 49 from 2-
chloro-
3N-(2-benzimidazolylamino)-4-methylthiophene using one equivalent of
methanesulfonic acid. Colorless crystals. M.p.: 227 C
CA 02488242 2004-12-01
58
Example 51: 2-Chloro-3N-(2-benzimidazolylamino)-4-methylthiophene benzoate
0 \ /
HO
0 N>-H
~ N
N
H
CI s
was obtained analogously to the procedure described in example 49 from 2-
chloro-3N-
(2-benzimidazolylamino)-4-methylthiophene using one equivalent of benzoic
acid. For
the precipitation, the reaction mixture was concentrated to half of its
original volume,
and ether (30 ml) was then added. Colorless crystals, m.p.: 198 C
Example 52: 2,4-Dichloro-3N-(2-benzimidazolylamino)thiophene hydrochloride
x HCI
O:N
>_H CI
H
CI S
a) Methyl 3-acetylaminothiophene 2-carboxylate
With simultaneous heating in an oil bath, 567 ml of acetic anhydride are added
dropwise to a mixture of 942 g of methyl 3-aminothiophene-2-carboxylate and 1
000 ml
of toluene, and the mixture is then boiled under reflux conditions for 1'/2
hours and
subsequently cooled in an ice bath to about 0 C. The crystals are filtered off
and
washed twice with a little isopropanol and twice with diisopropyl ether.
Methyl 3-
acetylaminothiophene-2-carboxylate can be obtained from the filtrate by
further
concentration and crystallization. M.p. 93-95 C.
b) Methyl 3-acetylamino-4,5-dichlorothiophene-2-carboxylate
With magnetic stirring at a reaction temperature of 20-30 C, 17.9 g of
sulfuryl chloride
S02C12 are added dropwise to a solution of 19.9 g of methyl 3-
acetylaminothiophene-2-
carboxylate in 100 ml of chloroform. The mixture is then stirred at 40 C for
another
2 hours and boiled under reflux conditions for another 15 minutes. The solvent
is
distilled off under reduced pressure, ethyl acetate is then added to the
residue and the
CA 02488242 2004-12-01
59
crystals are, after standing, filtered off. M.p. 136-138 C.
c) Methyl 3-acetylamino-4 chlorothiophene-2-carboxylate
A mixture of 25 g of methyl 3-acetylamino-4,5-dichlorothiophene-2-carboxylate,
about
10 g of triethylamine, 300 ml of methanol and 1 g of palladium on carbon is,
at room
temperature and under atmospheric pressure, hydrogenated until the uptake of
hydrogen has stopped. The catalyst is filtered off and the mixture is then
concentrated
by distillation under reduced pressure until crystallization begins, water is
then added
and the solid is filtered off. Colorless crystals from isopropanol. M.p. 142-
147 C.
d) Methyl 3-amino-4-chlorothiophene-2-carboxylate
In a mixture of 50 ml of methanol and 50 ml of concentrated hydrochloric acid,
7 g of
methyl 3-acetylamino-4-chlorothiophene-2-carboxylate are stirred at 60 C for 4
hours,
under reflux for 5 hours and at room temperature for another 3 days. Any
precipitate
that has formed is removed by filtration, and about 1/3 of the volume of the
solvent is
removed by distillation under reduced pressure. Following addition of about
100 ml of
water, the mixture is stirred at room temperature for another 15 minutes and
the
colorless crystals are filtered off and dried in a stream of air. M.p.: 62-64
C.
e) 3-Amino-4-chlorothiophene
18.02 g of methyl 3-amino-4-chlorothiophene-2-carboxylate are added to a
solution of
11.1 g of KOH and 160 ml of water and the mixture is then boiled under reflux
for
3 hours and, after cooling, added dropwise to a solution, which is at 60 C, of
15 ml of
concentrated hydrochloric acid and 30 ml of water. This results in a vigorous
evolution
of CO2. After further stirring at 60 C for about 40 minutes, the mixture is
allowed to
cool, a layer of 50-100 ml of methyl tert-butyl ether is added, the mixture is
made
alkaline using concentrated aqueous sodium hydroxide solution and the aqueous
phase is extracted in a separating funnel. The aqueous phase is extracted two
more
times with methyl tert-butyl ether, and the combined organic extracts are
washed once
with water in a separating funnel. The organic phase is dried, the solvent is
distilled off
and the oily-amorphous residue is chromatographed on a silica gel column using
a
mixture of 1 part of ethyl acetate and 1 part of toluene.
CA 02488242 2004-12-01
f) 4-Chloro-3-thienyl isothiocyanate
1.46 g of thiocarbonyldiimidazole are added to a solution of 1.1 g of 3-amino-
4-
chlorothiophene in 20 ml of anhydrous THF, and the mixture is stirred at room
temperature for one hour. The solid is distilled off under reduced pressure,
the residue
5 is dissolved in ethyl acetate, the organic phase is treated twice with water
in a
separating funnel and then dried, and the solvent is again distilled off under
reduced
pressure. This gives 4-chloro-3-thienyl isothiocyanate as a dark oil which is
then
reacted further without further purification steps.
10 g) N-(2-Aminophenyl)-N'-(4-chloro-3-thienyl)thiourea
0.86 g of 1,2-diaminobenzene (o-phenylenediamine) is added to a solution of
1.4 g of
4-chloro-3-thienyl isothiocyanate in 40 ml of anhydrous THF, the mixture is
stirred at
room temperature for about 20 hours and the solvent is distilled off under
reduced
pressure. The residue is treated with water and extracted with ethyl acetate,
the
15 solvent is distilled off again and the residue is purified using medium-
pressure silica gel
column chromatography using a 1:1 mixture of ethyl acetate and toluene. Brown-
yellow solid.
h) 4-Chloro-3N-(2-benzimidazolylamino)thiophene
20 A solution of 0.169 g of sodium hydroxide in 5 ml of water, followed by a
solution of
0.363 g of p-toluenesulfonyl chloride in 10 ml of THF, is added to a solution
of 0.5 g of
N-(2-aminophenyl)-N'-(4-chloro-3-thienyl)thiourea in 25 ml of anhydrous THF.
The
mixture is stirred at room temperature for 3 hours, the solvent is then
distilled off under
reduced pressure and the residue is treated with water and extracted with
ethyl
25 acetate. After removal of the solvent by distillation, the product is
purified by medium-
pressure silica gel chromatography using a mixture of 20 parts of ethyl
acetate,
10 parts of n-heptane and 3 parts of glacial acetic acid as eluent.
For characterization, a small portion of the 4-chloro-3N-(2-
benzimidazolylamino)-
30 thiophene was, in ethyl acetate, using ethereal hydrogen chloride solution,
converted
into 4-chloro-3N-(2-benzimidazolylamino)thiophene hydrochloride and
characterized.
Colorless crystals. M.p.: 256-260 C.
CA 02488242 2004-12-01
61
i) 2,4-Dichloro-3N-(2-benzimidazolylamino)thiophene hydrochloride
A solution of 0.16 g of N-chlorosuccinimide in 5 ml of glacial acetic acid is
added to a
solution of 0.3 g of 4-chloro-3N-(2-benzimidazolylamino)thiophene in 10 ml of
glacial
acetic acid. The reaction mixture is stirred at 40 C for 15 minutes and at
room
temperature for about 4 hours, the acetic acid is then distilled off under
reduced
pressure and the residue is treated with water. The mixture is made alkaline
using
aqueous sodium hydroxide solution and then extracted with ethyl acetate, the
extract is
washed with water, the organic phase is dried and the solvent is distilled off
under
reduced pressure. The residue is purified under medium-pressure conditions by
column chromatography using a mixture of 20 parts of ethyl acetate, 10 parts
of
n-heptane and 3 parts of glacial acetic acid as eluent and then precipitated
from ethyl
acetate by addition of a solution of hydrogen chloride in diethyl ether.
Colorless
crystalline product. M.p. 264-268 C.
Example 53:
2-Bromo-4-chloro-3N-(2-benzimidazolylamino)thiophene hydrochloride
x Ha
N>_H CI
N
H
Br S
A solution of 0.356 g of N-bromosuccinimide in 6 ml of glacial acetic acid is
added
dropwise to a solution of 0.5 g of 4-chloro-3N-(2-
benzimidazolylamino)thiophene in
15 ml of glacial acetic acid, and the mixture is stirred at room temperature
for another
15 minutes. The solvent is distilled off and the residue is treated with water
and made
alkaline using aqueous sodium hydroxide solution. Following extraction with
ethyl
acetate, the organic phase is washed with water, dried and concentrated under
reduced pressure. The residue is chromatographed on silica gel using medium-
pressure conditions and a mixture of 20 parts of ethyl acetate, 10 parts of n-
heptane
and 3 parts of glacial acetic acid as eluent. Following distillative removal
of the solvent,
the residue is taken up in ethyl acetate and 2-bromo-4-chloro-3N-(2-
benzimidazolyl-
amino)thiophene hydrochloride is precipitated by addition of a solution of
hydrogen
CA 02488242 2004-12-01
62
chloride gas in diethyl ether. Colorless crystalline product. M.p.: 264-266 C.
Example 54: ~(2,4-Dichlorothiophen-3-yi)(5-fluoro-1 H-benzimidazol-2-yl)amine
hydrochloride
a) 1-(2-Amino-4-fluorophenyl)-3-(4-chlorothiophen-3-yl)thiourea
NH2 H H CI
NYN
F S S
4-Fluoro-1,2-phenylenediamine (900 mg) was dissolved in THE (25 ml), and 4-
chloro-
3-thienyl isothiocyanate (example 52c), dissolved in THE (15 ml), was added
dropwise
with stirring. The solution was stirred at room temperature for about 3 hours
and then
allowed to stand overnight. The reaction mixture was then concentrated, and
the
residue was purified by preparative HPLC. The product-containing fractions
were
combined, freed from acetonitrile, made basic and extracted three times with
ethyl
acetate. The organic phases were combined, dried (MgSO4) and filtered. Removal
of
the solvent gave 625 mg of the desired product.
LCMS-Rt (F): 1.28 min
MS (ES+, M+H+): 302.0
b) (4-Chlorothiophen-3-yl)(5-fluoro-1 H-benzimidazol-2-yl)amine
F N
H
\>- N CI
H
S
1-(2-Amino-4-fluorophenyl)-3-(4-chlorothiophen-3-yl)thiourea (625 mg) was
dissolved
in THF, and a solution of NaOH (0.207 g) in water (9 ml) was added. Over a
period of
5 min, a solution of p-toluyl chloride (0.395 g) in THE (10 ml) was added
dropwise.
After the addition had ended, the mixture was stirred at room temperature for
one hour.
For work-up, water and ethyl acetate were added to the reaction mixture, and
the
phases were separated in a separating funnel. The aqueous phase was extracted
CA 02488242 2004-12-01
63
three times with ethyl acetate and the combined ethyl acetate phases were
dried with
magnesium sulfate, clarified with charcoal, filtered and concentrated. This
gave
135 mg of the desired product.
LCMS-Rt (F): 0.90 min
MS (ES+, M+H+): 268.0
c) (2,4-Dichlorothiophen-3-yl)(5-fluoro-1 H-benzimidazol-2-yl)amine
hydrochloride
F N H
~>--N CI
N
S
HC) Cl
(4-Chlorothiophen-3-yl)(5-fluoro-1 H-benzimidazol-2-yl)amine (85 mg) was
dissolved in
glacial acetic acid (4 ml), and N-chlorosuccinimide (42 mg), dissolved in
glacial acetic
acid (4 ml), was slowly added at room temperature, with vigorous stirring.
After the
addition had ended, the mixture was stirred at room temperature for 45 min and
then at
50 C for 5 h. After the addition of further N-chlorosuccinimide (4 mg)
stirring at 50 C
was continued for one hour. Toluene (20 ml) was then added to the reaction
mixture,
and the glacial acetic acid was distilled off. The residue was dissolved in
ethyl acetate
and eluted using saturated potassium carbonate solution. The ethyl acetate
phase was
dried over magnesium sulfate, filtered and concentrated. The residue was
purified by
preparative HPLC and the product-containing fractions were combined, freed
from
acetonitrile, made basic and extracted three times with ethyl acetate. The
organic
phases were combined, dried (MgSO4) and filtered. After removal of the
solvent, water
and 2N hydrochloric acid were added to the residue, which was then freeze-
dried. This
gave 17 mg of the desired product.
LCMS-Rt (E): 2.65 min
MS (ES+, M+H+): 301.93
CA 02488242 2004-12-01
64
Example 55: (2-Bromo-4-chlorothiophen-3-yl)(5-fluoro-1 H-benzimidazol-2-
yl)amine F`s
hydrochloride
F N H
)---N CI
N
HCI Br S
(4-Chlorothiophen-3-yl)(5-fluoro-1 H-benzimidazol-2-yl)amine (50 mg, example
54b)
was dissolved in glacial acetic acid (4 ml), and N-bromosuccinimide (33 mg),
dissolved
in glacial acetic acid (4 ml), was slowly added at room temperature, with
vigorous
stirring. After the addition had ended, the mixture was stirred at room
temperature for
45 min, toluene (20 ml) was then added to the reaction mixture and the glacial
acetic
acid was distilled off. The residue was dissolved in ethyl acetate and washed
with
saturated potassium carbonate solution. The ethyl acetate phase was dried over
magnesium sulfate, filtered and concentrated. The residue was purified by
preparative
chromatography and the product-containing fractions were combined, freed from
acetonitrile, made basic and extracted three times with ethyl acetate. The
organic
phases were combined, dried (MgSO4) and filtered. After removal of the
solvent, water
and 2 N hydrochloric acid were added to the residue, which was then freeze-
dried.
This gave 27 mg of the desired product.
LCMS-Rt (E): 2.29 min
MS (ES , M+H+): 347.87
Example 56: (2,4-Dichlorothiophen-3-yl)(5,6-difluoro-1 H-benzimidazol-2-
yl)amine
hydrochloride
a) 1-(2-Amino-4,5-difluorophenyl)-3-(4-chlorothiophen-3-yl)thiourea
CA 02488242 2004-12-01
F NH2
CI
F NH
S
S N
H
1,2-Diamino-4,5-difluorobenzene (1.02 g) was initially charged in abs. THE (15
ml),
and 4-chloro-3-thienyl isothiocyanate (1.25 g, example 52c), dissolved in abs.
THE
(15 ml), was added dropwise. Further treatment analogously to example 54a)
gave
5 773 mg of the desired compound.
LCMS-Rt (F): 1.32 min
MS (ES+, M+H+): 320.0
b) (4-Chlorothiophen-3-yl)(5,6-difluoro-1 H-benzimidazol-2-yl)amine
F N H
Cl
F N
H
S
1-(2-Amino-4,5-difluorophenyl)-3-(4-chlorothiophen-3-yl)thiourea (773 mg) was
initially
charged in THE (20 ml), and a solution of NaOH (240 mg) in water (9 ml)
followed by a
solution of tosyl chloride (528 mg) in THE (10 ml) were added. Further
treatment
analogously to example 54b) gave 275 mg of the desired compound.
LCMS-Rt (F): 0.95 min
MS (ES+, M+H+): 286
c) (2,4-Dichlorothiophen-3-yl)(5,6-difluoro-1 H-benzimidazol-2-yl)amine
hydrochloride
F \ H
I >-N CI
F N
HCI CI
CA 02488242 2004-12-01
66
(4-Chlorothiophen-3-yl)(5,6-difluoro-1 H-benzimidazol-2-yl)amine (125 mg) was
initially
charged in acetic acid (8 ml), and a solution of CI-succinimide (59 mg) in
acetic acid
(2 ml) was added dropwise. Further treatment analogously to example 54c) gave
58 mg of the desired product.
LCMS-Rt (E): 2.97 min
MS (ES+, M+H+): 319.88
Example 57: (2-Bromo-4-chlorothiophen-3-yl)(5,6-difluoro-1 H-benzimidazol-2-
yl)amine
hydrochloride
F N
CI
N
F
N Brb\
(4-Chlorothiophen-3-yl)(5,6-difluoro-1 H-benzimidazol-2-yl)amine (125 mg,
example 55b) was dissolved in glacial acetic acid (8 ml), and N-
bromosuccinimide
(78 mg) dissolved in glacial acetic acid (2 ml), was slowly added at room
temperature,
with vigorous stirring. Further treatment analogously to example 55c) gave 77
mg of
the desired product.
LCMS-Rt (E): 2.39 min
MS (ES+, M+H+): 365.86
Example 58: 4-Chloro-3N-(4-methyl-2-benzimidazolylamino)thiophene
hydrochloride
x HCl
N H Cl
H
S
a) N-(2-Amino-3-methyl phenyl)-N'-(4-chloro-3-thienyl)thiourea
is obtained analogously to the procedure given in example 52g) from 4-chloro-3-
thienyl
isothiocyanate and 1,2-diamino-3-methylbenzene, using medium pressure column
CA 02488242 2004-12-01
67
chromatography on silica gel with a mixture of 20 parts of ethyl acetate, 10
parts of
n-heptane and 1 part of ethyl acetate. Brownish-yellow solid, m.p.: 193-196 C.
b) e) 4-Chloro-3N-(4-methyl-2-benzimidazolylamino)thiophene
is obtained analogously to the procedure given in example 52h) from N-(2-amino-
3-
methylphenyl)-N'-(4-chloro-3-thienyl)thiourea using medium pressure column
chromatography on silica gel with a mixture of 10 parts of dichloromethane and
1 part
of methanol, as an amorphous, foam-like product. Preparation of the 4-chloro-
3N-(4-
methyl-2-benzimidazolylamino)thiophene hydrochloride in ethyl acetate using
diethyl
ether saturated with hydrogen chloride gas. Crystalline product, m.p. 325-327
C.
Example 59: 2,4-Dichloro-3N-(4-methyl-2-benzimidazolylamino)thiophene
hydrochloride
xHCI
N
H CI
\>- N
H
CI S
is obtained analogously to the procedure given in example 52i) from 4-chloro-
3N-(4-
methyl-2-benzimidazolylamino)thiophene and N-chlorosuccinimide in glacial
acetic
acid, with analogous work-up. Crystalline product, m.p. 296-298 C.
Example 60: trans-(3aS,7aS)-4-Chloro-3N-(3a,4,5,6,7,7a-hexahydro-1 H-2-
benzimidazolyl)-3-thienylamine hydrochloride
x HCI
H CI
H 1~
S
a) trans-S,S-3N-(2-Aminocyclohexyl)-N'-(4-chloro-3-thienyl)thiourea
CA 02488242 2004-12-01
68
is obtained analogously to the reaction given in example 1, b) from 4-chloro-3-
thienyl
isothiocyanate and trans-S,S-1,2-d iaminocyclohexane by column-chromatographic
separation on silica gel using a mixture of 10 parts of ethyl acetate, 5 parts
of
dichloromethane, 5 parts of n-heptane, 5 parts of methanol and 1 part of
ammonia
(35-37%), as an amorphous dark product which is processed further without
further
work-up.
b) trans-(3aS, 7aS)-4-Chloro-3N-(3a,4,5,6,7,7a-hexahydro-1 H-2-benzimidazolyl)-
3-
thienylamine
is obtained analogously to the procedure given in example 52h) from trans-S,S-
3N-(2-
aminocyclohexyl)-N'-(4-chloro-3-thienyl)thiourea, p-toluenesulfonyl chloride
and
subsequent application of medium pressure column chromatography on silica gel
using a mixture of 10 parts of dichloromethane and I part of methanol, as an
amorphous, foam-like product. Preparation of the trans-S,S-4-chloro-3N-
(3a,4,5,6,7,7a-hexahydro-1 H-2-benzimidazolyl)-3-thienylamine hydrochloride in
ethyl
acetate and a little ethanol using diethyl ether saturated with hydrogen
chloride gas.
Crystalline product, m.p. 196-200 C.
Example 61: trans-(3aR,7aR)-4-Chloro-3N-(3a,4,5,6,7,7a-hexahydro-1 H-2-
benzi mid azolyl)-3-thienyl a mine hydrochloride
x HC1
N H C!
\
H
a) trans-(1 R,2R)-3N-(2-Aminocyclohexyl)-N'-(4-chloro-3-thienyl)thiourea
is obtained analogously to the reaction given in example 1, b) from 4-chloro-3-
thienyl
isothiocyanate and trans-(1 R,2R)-(-)-1,2-diaminocyclohexane by subsequent
column-
chromatographic separation on silica gel using a mixture of 10 parts of ethyl
acetate,
5 parts of n-heptane, 5 parts of dichloromethane, 5 parts of methanol and 1
part of
ammonia (35-37%), as an amorphous, dark product which is processed further
without
further work-up.
CA 02488242 2004-12-01
69
b) trans-(3aR, 7aR)-4-Chloro-3N-(3a,4,5,6,7,7a-hexahydro-1 H-2-benzimidazolyl)-
3-
thienylamine
is obtained analogously to the procedure given in example 52h) from trans-R,R-
3N-(2-
aminocyclohexyl)-N'-(4-chloro-3-thienyl)thiourea, p-toluenesulfonyl chloride
and
subsequent application of medium pressure column chromatography on silica gel
using a mixture of 10 parts of ethyl acetate, 5 parts of n-heptane, 5 parts of
dichloromethane, 5 parts of methanol and 1 part of ammonia (35-37%), as an
amorphous, oily product. Preparation of the trans-R,R-4-chloro-3N-
(3a,4,5,6,7,7a-
hexahydro-1 H-2-benzimidazolyl)-3-thienylamine hydrochloride in ethyl acetate
and a
little ethanol using diethyl ether saturated with hydrogen chloride gas.
Crystalline
product, m.p. 240-244 C.
Example 62: cis-4-Chloro-3N-(3a,4,5,6,7,7a-hexahydro-1 H-2-benzimidazolyl)-3-
thienylamine hydrochloride
H x HCI
H CI
~~--N \b\
H H
S
a) cis-3N-(2-Aminocyclohexyl)-N'-(4-chloro-3-thienyl)thiourea
is obtained analogously to the reaction given in example 1, b) from 4-chloro-3-
thienyl
isothiocyanate and cis-1,2-diaminocyclohexane by subsequent column-
chromatographic separation on silica gel using a mixture of 10 parts of ethyl
acetate,
5 parts of n-heptane, 5 parts of dichloromethane, 5 parts of methanol and 1
part of
ammonia (35-37%), as an amorphous, dark product which is processed further
without
further work-up.
b) cis-4-Chloro-3N-(3a,4,5,6,7,7a-hexahydro-1 H-2-benzimidazolyl)-3-
thienylamine
is obtained analogously to the procedure given in example 52h) from 3N-(cis-2-
amino-
cyclohexyl)-N'-(4-chloro-3-thienyl)thiourea, p-toluenesulfonyl chloride and
subsequent
CA 02488242 2004-12-01
application of medium pressure column chromatography on silica gel using a
mixture
of 10 parts of ethyl acetate, 5 parts of n-heptane, 5 parts of
dichloromethane, 5 parts of
methanol and 1 part of ammonia (35-37%), as a brown, oily product. Preparation
of the
4-chloro-3N-(cis-3a,4,5,6,7,7a-hexahydro-1 H-2-benzimidazolyl)-3-thienylamine
hydro-
5 chloride in ethyl acetate and a little ethanol, using diethyl ether
saturated with
hydrogen chloride gas. Crystalline product, m.p. 228-231 C.
Example 63: trans-R,R-2,4-Dichloro-3N-(3a,4,5;6,7,7a-hexahydro-1 H-
benzimidazolyl)
3-thienylamine hydrochloride
xHCI
N H CI
Jfj \>-N
H
10 CI S
is obtained analogously to the procedure given in example 52i) by reacting
trans-R,R-
4-chloro-3N-(3a,4,5,6,7,7a-hexahydro-1 H-2-benzimidazolyl)-3-thienylamine with
N-chlorosuccinimide and analogous work-up. Crystalline product. Foaming with
sublimation starting at 165 C.
Example 64: cis-2,4-Dichloro-3N-(3a,.4,5,6,7,7a-hexahydro-1 H-2-
benzimidazolyl)-3-
thienylamine hydrochloride
H x HCI
N H CI
~_N
H H
CI S
is obtained analogously to the procedure given in example 52i) by reacting cis-
4-
chloro-3N-(3a,4,5,6,7,7a-hexahydro-1 H-2-benzimidazolyl)-3-thienylamine with
N-chlorosuccinimide and analogous work-up. Crystalline product. M.p. 270-274
C.
CA 02488242 2004-12-01
71
Example 65: 4-Chloro-3N-(4-chloro-2-benzimidazolylamino)thiophene
hydrochloride
CI X HCI
H CI
N
H
a) 1-N-(2-Amino-3-chlorophenyl)-3-N-(4-chloro-3-thienyl)thiourea
is obtained from 3-chloro-1,2-diaminobenzene and 4-chloro-3-thienyl
isothiocyanate
analogously to the procedure described in example 1 b) and crystallization
under
diisopropyl ether, as a solid having two melting points: m.p. 1: 152-155 C
with
recrystallization; m.p. 2: >310 C
b) 4-Chloro-3N-(4-chloro-2-benzimidazolylamino)thiophene
is obtained analogously to the procedure described in example 52h) by reacting
1-N-
(2-amino-3-chlorophenyl)-3-N-(4-chloro-3-thienyl)thiourea with p-
toluenesulfonyl
chloride and column chromatography on silica gel using a mixture of 3 parts of
toluene
and 1 part of ethyl acetate as mobile phase and subsequent distillative
removal of the
solvent under reduced pressure, as a foam-like, amorphous product which is
converted further into the hydrochloride.
c) 4-Chloro-3N-(4-chloro-2-benzimidazolylamino)thiophene hydrochloride
is obtained by treating a solution of 4-chloro-3N-(4-chloro-2-
benzimidazolylamino)thiophene in ethyl acetate with a solution in diethyl
ether
saturated with hydrogen chloride gas, as a crystalline precipitate. M.p. 276-
280 C.
CA 02488242 2004-12-01
72
Example 66: 2,4-Dichloro-3N-(4-chloro-2-benzimidazolylamino)thiophene
hydrochloride
Cl x HCI
N ~'_N Cl
H
CI S
is obtained analogously to the procedure given in example 52i) from 4-chloro-
3N-(4-
methyl-2-benzimidazolylamino)thiophene and N-chlorosuccinimide in glacial
acetic
acid, with analogous work-up. Crystalline product, m.p. 294-297 C.
Analogously to the compounds listed in the working examples, it is possible to
prepare
the following thiophene derivatives:
2-bromo-4-chloro-3N-(4-methyl-2-benzimidazolylamino)thiophene hydrochloride,
m.p. 284-286 C,
2-bromo-4-chloro-3N-(4-chloro-2-benzimidazolylamino)thiophene hydrochloride,
m.p. 304-306 C,
trans-R,R-2-bromo-4-chloro-3N-(3a,4,5,6,7,7a-hexahydro-1 H-2-benzimidazolyl)-3-
thienylamine hydrochloride, point of decomposition: 215 C,
trans-(3aS,7aS)-2-bromo-4-chloro-3N-(3a,4,5,6,7,7a-hexahydro-1 H-2-
benzimidazolyl)-
3-thienylamine hydrochloride 243-254 C,
2,4-dibromo-3N-(2-benzimidazolyl)-3-thienylamine hydrochloride,
2,4-dimethyl-3N-(2-benzimidazolyl)-3-thienylamine hydrochloride,
2,4-dimethyl-3N-(4-methyl-2-benzimidazolyl)-3-thienylamine hydrochloride,
2,4-dimethyl-3N-(5-fluoro-2-benzimidazolyl)-3-thienylamine hydrochloride,
2-chloro-3N-(4-butoxy-2-benzimidazolyl)-4-methyl-3-thienylamine hydrochloride,
2-chloro-3N-(4-trifluoromethyl-2-benzimidazolyl)-4-methyl-3-thienylamine
hydrochloride,
2-chloro-3 N-(4-methylsulfonyl-2-benzimidazolyl)-4-methyl-3-thienylamine
hydrochloride.
CA 02488242 2004-12-01
73
Pharmacological data:
Test description:
In this test, the recovery of the intracellular pH (pHi) after an
acidification, which starts
when the NHE is capable of functioning, even under bicarbonate-free
conditions, was
determined. For this purpose, the pHi was determined using the pH-sensitive
fluorescent dye BCECF (Calbiochem, the precursor BCECF-AM is employed). The
cells were initially loaded with BCECF. The BCECF fluorescence was determined
in a
"ratio fluorescence spectrometer" (Photon Technology International, South
Brunswick,
N.J., USA) with excitation wavelengths of 505 and 440 nm and an emission
wavelength of 535 nm, and was converted into the pHi using calibration plots.
The
cells were incubated in NH4CI buffer (pH 7.4) (NH4CI buffer: 115 mM NaCl, 20
mM
NH4CI, 5 mM KCI, 1 mM CaC12, 1 mM MgSO4, 20 mM Hepes, 5 mM glucose, 1 mg/ml
BSA; a pH of 7.4 is established with 1 M NaOH) even during the BCECF loading.
The
intracellular acidification was induced by addition of 975 ,u1 of an NH4CI-
free buffer (see
below) to 25 p1 aliquots of the cells incubated in NH4CI buffer. The
subsequent rate of
pH recovery was recorded in the case of NHE1 for two minutes, in the case of
NHE2
for five minutes and in the case of NHE3 for three minutes. To calculate the
inhibitory
power of the tested substances, the cells were initially investigated in
buffers in which
complete or absolutely no pH recovery took place. For complete pH recovery
(100%),
the cells were incubated in Na+-containing buffer (133.8 mM NaCl, 4.7 mM KCI,
1.25 mM CaCI2, 1.25 mM MgC12, 0.97 mM Na2HPO4, 0.23 mM NaH2PO4, 5 mM
Hepes, 5 mM glucose, a pH of 7.0 is established with 1 M NaOH). To determine
the
0% value, the cells were incubated in an Nay'-free buffer (133.8 mM choline
chloride,
4.7 mM KCI, 1.25 mM CaCI2, 1.25 mM MgC12, 0.97 mM K2HPO4, 0.23 mM KH2PO4, 5
mM Hepes, 5 mM glucose, a pH of 7.0 is established with 1 M KOH). The
substances
to be tested were made up in the Na+-containing buffer. Recovery of the
intracellular
pH at each tested concentration of a substance was expressed as a percentage
of the
maximum recovery. Using the Sigma-Plot program, the IC50 value of the
substance in
CA 02488242 2004-12-01
74
question was calculated for the individual NHE subtypes using the percentages
for pH
recovery.
Results:
Example IC50 (PM],
16
trans-R,R-2-chloro-3N-(3a,4,5,6,7,7a-hexahydro-1 H-2- 0.27 (rNHE3)
benzimidazolyl)-4-methyl-3-thienylamine hydrochloride
12
2-chloro-3N-(2-benzimidazolyl)-4-methyl-3-thienylamine 0.12 (rNHE3)
hydrochloride
54:
2-bromo-4-chloro-3N-(2-benzimidazolylamino)thiophene 0.22 (hNHE3)
hydrochloride
53:
2,4-dichloro-3N-(2-benzimidazolyl amino)thiophene 0.14 (hNHE3)
hydrochloride
56:
2,4-dichloro-3N-(4-methyl-2-benzimidazolyl- 0.22 (hNHE3)
amino)thiophene hydrochloride
60:
trans-R,R-2,4-dichloro-3N-(3a,4,5,6,7,7a-hexahydro-1 H- 0.19 (hNHE3)
2-benzimidazolyl)-3-thienylamine hydrochloride
63:
2,4-d ich lo ro-3 N -(4-ch loro-2-benzi mid azolyl- 0.54 (hNHE3)
amino)thiophene hydrochloride
38:
2-chloro-3N-(4-hydroxy-2-benzimidazolylamino)-4- 0.84 (hNHE3)
methylthiophene hydrochloride
CA 02488242 2004-12-01
18:
2-bromo-3N-(2-benzimidazolyl)-4-methyl-3-thienylamine 0.12 (hNHE3)
hydrochloride
19:
trans-R,R-2-bromo-3N-(3a,4,5,6,7,7a-hexahydro-1 H-2- 0.56 (hNHE3)
benzimidazolyl)-4-methyl-3-thienylamine hydrochloride
2:
2-chloro-3N-(5-fluoro-2-benzimidazolyl)-4-methyl-3- 0.62 (hNHE3)
thienylamine hydrochloride
44:
(1 H-benzimidazol-2-yl)-(2-chloro-4-methylthiophen-3-yl)- 1.59 (hNHE3)
methylamine
