Note: Descriptions are shown in the official language in which they were submitted.
` ~2~Z'~7~
ANTI-SPASMODI _AGENTS HAVING
A RING IN THE MAIN CHAIN
Background of -the Inven-tion
Field of the Invention
The present invention relates to new pharmaceutical
compounds having useEul anti-spasmodic properties.
Description of the Prior Ar-t
The purpose of an anti-spasmodic drug is to relieve
spasms of the smooth muscles. Smooth muscles line most
of the visceral organs. The peristalsis and muscular
activity of the stomach, in-testines, gall bladder, urinary
bladder, lung, the uterus, and to a degree the heart are
all largely controlled by smooth muscles. Smooth muscles
are innervated by the autonomic nervous system. The
autonomic nervous system consists of two antagonistic
branches--the sympathetic branch and the parasympathetic
branch. On all visceral organs except the heart the para-
sympathetic nerve impulses increase the irri-tability and
tension of the smooth muscles; contrariwise, the sympa-
thetic nerve lmpulses increase -the tension and irrita-
bility of the muscles of the heart muscle and relax the
smooth muscles of the other visceral organs.
A spasm in a smooth muscle may be due -to one of
-two causes. Either the smooth muscle may be receiving
exaggera-ted impulses from the autonomic nervous system
which create violent contractions in the muscle, or
-the muscle may be intrinsically stimula-ted into a spasm
(most likely from chemical changes in the surrounding
tissue). A spasm due to exaggerated impulses from the
parasympathetic branch of the autonomic nervous system
may oEten be corrected by administering a-tropine (an
active alkaloid of belladonna which serves -to break a
connection between -the parasympathe-tic nerve and the
9;~
smooth muscle. This ability and effect of atropine is call-
ed a "neurotropic effect". A spasm intrinsic in -the smooth
muscle itself may often be corrected by papaverine (a deriv-
ative of opium which is classed as a narcoti.c)~ Papaverine
has an ability to decrease in-trinsically the contractility
of smooth muscle; it has the ability to relax smooth muscles
directly. This ability and effect of papaverine is called a
"musculotropic effect".
In relieving spasms of smooth muscles generally, a mus-
culotropic effect is acknowledged to be superior to a neuro-
tropic effect. A neurotropic effect cannot relieve spasms
intrinsic in the smooth muscle itself, while a musculotropic
effect, by relaxing and decreasing the irritability and re-
sponsiveness of smooth muscle to stimulation from the auto-
nomic nervous system, can help to relieve a smooth musclespasm even when it is due to exaggerated impulses from the
autonomic nervous system.
A clinical difficulty with atropine is that oE un-
desirable side-reactions. Atropine when given in effective
doses, serves -to break or partly break all the parasympa-
thetic nerve-smooth muscle connections throughout the body.
Thus when atropine is given in sufficient dosage to relieve
a spasm in a specific visceral organ, such as a gastric or
intestinal spasm (the spasm caused by exaggerated nerve im-
pulses from the parasympathetic nervous system) undesirab]eside-actions due to the breaking oE the parasympathetic
nerve-muscle connections elsewhere in -the body may occur.
The most easily recognized of these undesirable si.de re-
actions are dilation of the pupi]. and dryness oE the mouth,
caused by the breaking of the parasympathetic connections to
-the iris and -the saliva producing mechanism respec-tively.
Atropine is ac]snowledged -to have also a musculotropic
effect, but its neurotropic effect is so strong that it
cannot be given in greater than minute doses (1/60 to 1/40
grain) without encountering the undesirable side reac-tions.
This dosage is too small to permit a significant musculo-
tropic effect.
Bl`
~Z~2~7~
U.S. Patent No. 2,390,555 discloses a class of com-
pounds comprising di-N-substi-tuted aminoethyl es-ters of
diphenylthioacetic acid of the general formula (C6H5)2-CFl-
COS-CH2CH2-R in which R represents a disubstituted amino
radical of either -the diethylamino group, the morpholino
group or the piperidino group. This patent was based upon
the discovery that the -thio analogs of certain disubstituted
acetic acid esters of aminoalcohols have desirable anti-
spasmodic properties. These compounds have proven to be
very effective and are widely used as anti-spasmodics with-
out encountering the undesirable side reactions due -to
excessive neurotropic effect.
U.S. Patent No. 4,432,977 discloses new uses, especial-
ly for the dilation of the smooth muscles of the upper
urinary tract, of the compounds disclosed in U.S. Patent No.
2,390,555.
In Compte Rendu de la Société de Biologie, 140, pp
477-9, (1946) Dupre, Levy and Tchoubar disclose a series
of compounds having -the formula (C6H5)(R)CHC(:O)SCH2CH2N-
(CH2CH3)2 where R is either a phenyl group, a propyl group,an isopropyl group, a butyl group or an isoamyl group.
These compounds are all disclosed as being spasmolytic
agents.
Compounds of the same general formula given above were
prepared by Tchoubar and Letellier-Dupre in Bulletin de la
Société Chimique, pp 792-4 (1947) wherein R was a phenyl
group, an ethyl group, a propyl group, an isopropyl group,
a butyl group, an isoamyl group or hydrogen.
In Farmakol. i. Toksikol., pp 10-17 (1956), Liberman
discloses a class of compounds having the general formula
(C6H5)2CHCOSCH2CH2N-R2, wherein both R's are the same and
are selected from methyl, ethyl, propyl and butyl groups;
and a class of compounds having the general formula
(C6H5)-CH(C6Hll)CSCH2CH2N-R2' wherein both R's are the
same and are selected from methyl, ethyl, propyl and butyl
groups.
~2~
C.A. Buehler et al in the Journal of Medicinal Chem-
istry, 6, pp 230-3 (1963) disclose physiologicall.y active
compounds of the general formula R(R')-C(OH)COS(CH2)2NR"2
wherein R and R' are aryl groups.
R~O. Clinton et al in the Journal of the American
Chemical Society, 68, pp 2076-7 (1946) synthesized a num-
ber of dialkyl aminoalkyl diarylthiolacetates including
fluorene-9-carbothioic acid, S-[2-diethylaminoethyl]
ester.
Summary of the Invention
A new class of anti-spasmodic compounds is provided
having -the general formula:
/(CH2)
R 1l S (C 2)m N\
where R is selected from the group consisting of:
CH -
1 2
'~3 ' ~'
-CH2- ' 3/
~CH2- ~3
CH
~Z~7~
~CH2 ~CH,-
. (~O-CH- whereln q
C~13~(CH2)q is an integer
~rom 1 to 4,
Cl~
CH3-C
CH3
~ ' .
~ .
O=C O
CH~
~3 C~ n (~ ~ f H -
HO- CH2 OH
~,`
2 ~
The total number of carl)on atom~s in R is equal to
or less ~ n 20 1 urtllcrn)orc!
m is an integer from 1 to 4;
n is an inte~er frorn 1 to 4;
p is an integer Erom'l to 4; ancl
X may be nonexistent or may be 0, S, Nll or CH~ or
salts thereof, but when X is noncxistent the terminal group
in both the n-chain and the p-chain is a methyl ~roup.
A preferred sub-genus, of the compounds hayin~ the
above-described general formula, incluc!es the following:
C S CH2 C~12 ~ ; C113,,C ~ C S CH2 CH2 N ~ ; and
~ (rO~C6115
O C1~3
~ o f~ l s cll2 C~12_~
CH3-tC~12)r wherein r is an inte~er Erom 1 to 4.
The present invention also comprises rnethods of administering
the above-de.scribed compounds Eor, but no~ limited to, the
treatment of patients suffering from pylorospasm in the
upper and lower ~astrointestinal tract, ~spasm associate~
with the gall bladder and comrnon bile cluc~, as well as
liarrhea, the irritable bowel syndrolne, ureterospasm, bladder
irritation, asthma and emphysema.
Description of the Preferred l~mbocliments
The anti-spasmodic compo~lnds of thc prescnt invention
are ef~ectlve ~n n d~s~,e ranp,e oE from about 1 to about 15
mg/kilo~ram of body weip7ht per day. ~ preferred dosap,e is in the
'5 ran~,e of from about 1.5 to about 11.5 mg/kilogram of body
wei~ht pcr day, ~ .5~ill more prcfcrred dosar,e range is from about 3
to about 6 m~/kilop,r.lln of l~ody weip,ht pcr clay.
The anti-spasmodic compounds oE the present invention
may be combined with a pharmaceutically acce~table carrier
~n and can be adminlstered orally, typically in tablets of 400
mg active ingredient, total 1155 mg, or by intravenous
injection, or by topical application.
.
~6-
--- lZ~ 7~
Because the anti-spasmodic compounds of -the present
invention generally hydrolyze slowly in water, -they are
preferably not used as a serum or suspension unless used
as a freshly prepared solution. It is possible, however,
to encapsulate microspheres of these compounds in the form
of a liquid suspension for administration -to patients.
As specific examples of the compounds of the present
invention, there can be mentioned:
4-t-butyl-benzoyl-thio-S-(2-diethylaminoe-thyl)-ester.HCl
3/ ~ CO-S-CH -CH -N-(CH CH ) HCl
as well as compounds of the following formulas:
~3
CH -CO-S-CH -CH -N-(CH CH CH CH ) HCl
H2-cH2-N-(cH2cH2cH3)2-
~ O-CH -CO-S-CH2-CH2-N-(CH2CH3)2
~ ~ ~ \ ~ CH _co-s-cH2-cEI2-cH2 N (C 3)2
2 CO S-CH2-N-CH2CH2CH2-NH
`~ / ~ 2 2 2 e2 2 \ 2/ 2
3 Z~2~7~
~ CH2CH3
, ~ CH2 CO S CH2 CH2N~
\
-CH2
~ O-CH-CO-S-CH -N-CH -CH -S
CH3-CH2-CH2-CH2-CH2
O-CH-CO-S-CH -CH -N-CH -CH . HCl
CH2-CH2-CH3
CH -CH
CH3 \ A
CH - C ~ CO-S-CH2-CH2-N-CH3 . HCl
CH3 CH -CH
; OH
1_CO S CH -CH ~N-(CH CH ) HCl
OH
H2-cH2-N-(cH2cH3)2-
~ CO-S-CH2-CH2-N ~ )
O=C O
> <
''~
~ 1000-85 4
~2~Z47~
~10-C~l
1 2
-cll-co-s-cll2-cll2-N-(c1l2c113)2 ~1
~10
Cl~-co-s-c~l2-cll2-N-(cll2cll3)2 ~ICl
. . _
The general reaction use~ in thc ~yn~hcsis of the anti-
spasmodic compounds described in the followinF, examples of
the present invention involves tlle nucleophilic substitution
of certain acyl cllloricles with certain ~l~iol compounds, st~ch
- as 2-diethylaminocthanethiol. This reaction is illustra~ed
in the following formula, wherein R is as defined above:
0 heat
R-C-Cl + IIS (CH2)2N(C2H5)2 ~Cl
acyl chloride 2-diethylaminoeth~nethiol
hydroctlloricle . .
o
R-c-s-(cl~2)2N(c2ll5)2 HCl
thiol ester hydrochloride
2-diethylaminoctllanethiol was ~urifiecl by re-distillation
in vaccuo an~ nitrogen gas. Sub~equently, thc thiol w~s
reacted with various acyl chlorides in ~ichloromethane by
combining tht! two reactants in a 1:1 molar ratio and ~,ently
heating under reflux condensa~ion ~or ap~roximately 1-2
hours. The reaction mixture was thcn cooled in ice-water
until crystalll7.ation occurred or, if nece.qsary, in dry ice-
ethanol. The crude crystal~q wcrc llarvest~ y suction
iltration and were then recryst~llLzed from an appropriate
solvent (e.~,. ethyl acctate, acetone, petroleum ether, or
dichloromethane).
The desired acyl chlorides may bc preparetl from the
carboxylic acid analogues by reac~ioll with oxalyl chlori~e
as follows:
_g
1000-85
~ heat
R-C-OH -~ CL-C-C-Cl ~ R-~-Cl -~ 11Cl ~ C02 ~ C0
carboxylie oxalyl acid
acid chloride chloride
.
The reaetion was performed under reflux eondensation.
Following the reaetion, which was usually complete within a
few hours, the aeid chlorides were vacuum-distilled and
reac~ed with a thiol compound as described above.
The eompounds of this lnvention nre anti-muscarinie
agents (cholinerp,ic-muscarinic receptor antap,onists) whieh
1~ inhibit the actions of acetylcholine on autonomic effectors
innervated 1~y post~,an~lionic choliner~,ic nerves as well as
on smooth muscle that lacks eholinerp,ic innervation. Sinee
a major component of parasympathetic control of smooth
rnuscle occurs via muscarinic receptors, these compounds are
effective as mocliiers of smooth m~scle activity.
Thiphenamil hydroehloride has been shown to decrease
spasm of the ~astrointestinal tract, biliary tract, ureter
and uterus without produein~ eharaeteristic atropinie side
effects on salivary and sweat ~lancls, GI ~,lands, the eye or
n the cardiovascular system. This invention results in eompouncls
which are as efficaeious as thiphenamil hydrochloride,'or
more so, in relaxin~, various .smooth muscle .systems while at
the same time demonstrating thiphenamil hclyrochloride's lack
of assoeiated side-effects. Pharmacolor~ical con~irmation of
these'a~ents included in vitro orp~an 1)ath work and development
of actual receptor-bindinp, dat~.
F,xample 1
-10-
1 ono-~5 ~2~2~74
The ~-t-butyl-benzoyl~thio-S-(dlethylaminoethyl)-ester'HCl
was tested uslng a muscar~nic receptor preparation ~ro~
r~b~it l~ng tissue. A mea~sure of the ability o this
compound to interact with muscarinic receptors, in this
preparation, was determined by ~he dep,ree to which the
compound competed w~th 13H] Quinuclidinyl Benzilate (hereinEfter
referred to as [3H]QNB~for muscarinic receptors ~nd thereby
inhibited the usual tissue upta~e of ~3HlQNB~ Fresh peripheral
lung tissue from New Zealand White rabbits was minced with
sclssors and homogenized wlth a polytron in 10 volume~ o
ice cold SOmM sodium phosphate buffer (p~l 7.4~. The homop,enate
w~s centrifur,ed ~1000 x ~, 5 min) and thc supcrnntant collec~cd.
The supernatant was then centrifu~,ed (42,000 x ~, 10'min,
4C) and the pellet res~spende~ ln buffer. Follow~ng a
fin~l centrifugat~on ~42,000 x g, 10 min, 4C) the resulting
pellet wa~ resuspended in 2 ml of phosph~te buffer f~r u~e
in binding assays.
The [3H]QNB blnding assay was performed by incubatinp.
aliquots of the lun~ homogcnates (0.8 mg ~rotein/assay) at
37C for 60 min in 2 ml of sodium phosphate buffer which
contained 0.1 nM ~311~QNB in the presence of 1 x 10 5 M
concentration of ~he nnti-spasmodic compound to determine
inhibition of 1311]QN~ bindlnp,. Followinr, incubatlon, the
assay was termin~ted by thc addit~on of ice-cold buffer and
rapid filtration throu~,h Whatman ~F-C~,la~s fiber fllters
under suction in n ~r~ndel~cell harvester. The filters were
remove~, placed individually in 8 ml of ficintillation cockt~il,
and counted for radioactivity in a scintill~tion spectrometer.
t3H]QNB whlch bound ln the pre6ence of 1 M atropine was
termed "nonspecific" and w~s .substracted from that which
bound in the nbsence of atrol-ine (e.~. "spcciflc" bindlnr,).
~11 poin~s wcre detcrmincd in dupllcate.
A~;
1000-85 . . ~ 7~ '
Compound/ Molecular Melting % inhibition of3H[~NB]
formula ~eight Point bindin~ (at a con-
(grams) (C) centrat~on o~'
of 1.0 x 10- ~1)
-- _ _
4-e-butyl-benzoyl-tllio-
S-(2-diethylaminoethyl)-
ester'HCl 329.9 16521%
(C~3)3-C ~ CO-S-
(CH2)2-N-(CH2C~3)2 HCl
-12- . .
`~ ~Zs~2~
Example 2
The pharmacological actions of one anti-spasmodic
compound was studied in a rabbit urinary bladder strip
preparation. In general, longitudinal strips were prepared
from the base of freshly isolated rabbit bladders and were
then suspended under near-physiological conditions in tissue
baths. The strips were attached to force transducers and
both contractile and relaxant activity was measured. To
measure the relaxant effects on the anti-spasmodic compounds
on previously-contracted bladder strips, the strips were
initially exposed to the muscarinic receptor agonist beth-
anechol and allowed to reach a steady level of contractile
activity for 20 minutes. At this point cumulative dose-
responses to the compound was recorded. The rabbit abdomens
were opened through a vertical midline incision. The
bladder and ure-thra were dissected free of all surrounding
tissues, removed and placed in aerated (95% 2 5% C2)
Kreb's~-bicarbonate buffer (pH:7.4) of the following compo-
sition (milliosmoles/liter):KCl 4.6, CaC12 2H2O 2.5, KH2PO4
1.2, MgSO4 7H2O 1.2, NaCl 118.2, NaHCO3 24.8, and glucose
10Ø Longitudinal muscle strips were prepared from the
bladder base (approximately 6 mm x 4 mm) and suspended in an
organ bath containing Kreb's buffer (37C) which was contin-
uously aerated with O2:CO2 (95%:5~). Tissues were allowed
to equilibrate to a tension of 2 gm for sixty minutes during
which time buffer was replaced at 20 minute in-tervals. The
contractile and relaxant responses of the muscle s-trips were
measured isometrically with a Sta-tham UC3~ force-displace-
ment transducer and recorded on an Electronics for Medicine
DR8~ oscillographic recorder. Bethanechol was employed as
the representative cholinergic agonis-t and, following
equilibration, was added to the baths for a final concen-
tration of 250 ~M. The tissues were allowed 20 minu-tes to
achieve a maintained level of contraction in response to
bethanechol and, at this point, cumulative dose-response
B~
-
~;292~
measurements for one anti-spasmodic compound were started
at concentrations ranging from 10 M -to 10 M. Solutions
were added in volumes up to 100 ~1 and were prepared Eresh
each day by dissolving them in distilled:deionized water.
Responses were measured 5 minu-tes following any particular
cumulative addition and were expressed as a percen-tage of
maximal relaxation (e.g. maximal relaxation is the base-
line or prebethanechol level of muscle tone).
Dose responses, measured from the standard bethane-
chol-contracted rabbit bladder strips, at various concen-
trations of 4-t-butyl-benzoyl--thio-S-(2-diethylaminoethyl)-
ester.HCl [(CH3)3-C ~ CO-S-(CH2)2-N-(CH2CH3)2.HCl] are
presented in Table I:
Table I
Concentration (moles/liter)
lo~8 10-7 1o~6 10-5 10-4
Increase in leng-th of
rabbit bladder s-trip
(cm) 0.1 0.2 0.4 1.3 3.2
20 Decrease in force o~
contraction of rabbit
bladder strip (gm) 0.02 0.04 0.08 0.27 0.67
% of maximum relaxation 1.3 2.6 5.2 16.5 40.5
% background relaxation 0.0 0.0 0.0 9.5 31.8
- 14 -
..
~:1
