Note: Descriptions are shown in the official language in which they were submitted.
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WO 99/43677 PCTIGB99100485
SUBSTITUTED 1.2.4-TRIAZOLO(3.4-aIPYRIDAZINE
The present invention relates to a substituted triazolo-pyridazine
derivative, to its use in therapy, to compositions containing it and to a
process for
its manufacture.
We have now discovered that it is possible to obtain medicaments which
have cognition enhancing effects which may be employed with less risk of
proconvulsant effects previously described with benzodiazepine receptor
partial
or full inverse agonists. Inverse agonists which are inverse agonists for the
a5
receptor and are relatively free of activity at al, a2 and a3 receptor binding
sites are preferred.
European Patent Applications 0085840 and 0134946 describe related
series of 1;2,4-triazolo[3,4-a]phthalazine derivatives which are stated to
possess
antianxiety activity. However, there is no disclosure nor any suggestion in
either
of these publications of the compounds of the present invention, nor that the
compounds disclosed in the Applications have any cognition enhancing
properties.
The present invention provides a compound which is:
3-(5-methylisoxazol-3-yl)-6-( 1-methyl-1, 2, 3-triazol-4-yl)methyloxy-1, 2, 4-
triazolo[3,4-a]phthalazine.
Cognition enhancement can be shown by testing the compound in the
Morris watermaze as reported by McNamara and Skelton, Psychobiology, 21:101-
108. The functional efficacy at the various receptor subtypes can be
calculated
using the method disclosed in WO-A-9625948.
Thus, for example, the compound of the present invention can be used in a
variety of disorders of the central neiwous system. Such disorders include
delirium, dementia and amnestic and other cognitive disorders. Examples of
delirium are delirium due to substance intoxication or substance withdrawal,
delirium due to multiple etiologies and delirium NOS (not otherwise
specified).
Examples of dementia are: dementia of the Alzheimer's type with early onset -
which can be uncomplicated or with delirium, delusions or depressed mood;
dementia of the Alzheimer's type, with late onset, which can be uncomplicated
or
with delirium, delusions or depressed mood; vascular dementia which can be
uncomplicated or with delirium, delusions or depressed mood; dementia due to
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HIV disease; dementia due to head trauma; dementia due to Parkinson's disease;
dementia due to Huntington's disease; dementia due to Pick's disease; dementia
.
due to Creutzfeld-Jakoh disease; dementia which is substance-induced
persisting
or due to multiple etiologies; and dementia NOS. Examples of amnestic
disorders are amnestic disorder due to a particular medical condition or which
is
substance-induced persisting or which is amnestic disorder NOS.
The invention also provides pharmaceutical compositions comprising the
compound of this invention and a pharmaceutically acceptable carrier.
Preferably these compositions are in unit dosage forms such as tablets, pills,
capsules, powders, granules, sterile parenteral solutions or suspensions,
metered
aerosol or liquid sprays, drops, ampoules, transdermal patches, auto-injector
devices or suppositories; for oral, parenteral, intranasal, sublingual or
rectal
administration, or for administration by inhalation or insufffation. For
preparing solid compositions such as tablets, the principal active ingredient
is
I5 mixed with a pharmaceutical carrier, e.g. conventional tableting
ingredients such
as corn starch, lactose, sucrose, sorbitoi, talc, stearic acid, magnesium
stearate,
dicalcium phosphate or gums or surfactants such as sorbitan monooleate,
polyethylene glycel, and other pharmaceutical diluents, e.g. water, to form a
solid
preformulation composition containing a homogeneous mixture of the compound
of the present invention, or a pharmaceutically acceptable salt thereof. When
referring to these preformulation compositions as homogeneous, it is meant
that
the active ingredient is dispersed evenly throughout the composition so that
the
composition may be readily subdivided into equally effective unit dosage forms
such as tablets, pills and capsules. This solid preformulation composition is
then
subdivided into unit dosage forms of the type described above containing from
0.1 to about 500 mg of the active ingredient of the present invention. Typical
unit dosage forms contain from 1 to 100 mg, for example 1, 2, 5, 10, 25, 50 or
100
mg, of the active ingredient. The tablets or pills of the novel composition
can be
coated or otherwise compounded to provide a dosage form affording the
advantage of prolonged action. For example, the tablet or pill can comprise an
inner dosage and an outer dosage component, the latter being in the form of an
envelope over the former. The two components can be separated by an enteric
layer which serves to resist disintegration in the stomach and permits the
inner
component to pass intact into the duodenum or to be delayed in release. A
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variety of materials can be used for such enteric layers or coatings, such
materials including a number of polymeric acids and mixtures of polymeric.
acids
with such materials as shellac, cetyl alcohol and cellulose acetate.
The liquid forms in which the novel compositions of the present invention
may be incorporated for administration orally or by injection include aqueous
solutions, suitably flavoured syrups, aqueous or oiI suspensions, and
flavoured
emulsions with edible oils such as cottonseed oii, sesame oil, coconut oil or
peanut oil, as well as elixirs and similar pharmaceutical vehicles. Suitable
dispersing or suspending agents for aqueous suspensions include synthetic and
natural gums such as tragacanth, acacia, alginate, dextran, sodium
carboxymethylcellulose, methylcellulose, polyvinyl-pyrroiidone or gelatin.
The present invention further provides the use of the compound of the
present invention in the manufacture of a medicament for the enhancement of
cognition, preferably in a human suffering from a dementing illness such as
Alzheimer's disease.
For the enhancement of cognition, a suitable dosage level is about 0.01 to
250 mg/kg per day, preferably about 0.01 to 100 mg/kg per day, and especially
about 0.01 to 5 mglkg of body weight per day. The compound may be
administered on a regimen of 1 to 4 times per day. In some cases, however,
dosage outside these limits may be used.
It is preferred that the compound of the present invention be ground, for
example using a pestle and mortar or industrial equivalent thereto, to a
particle
size of between 1 and 10 ~,M, and preferably less than 5 uM, before
formulation.
The compound may be micronised or sonicised by methods known in the art or
nanonised, for example by methods disclosed in US-A-5145684.
The present invention also provides a process for the production of the
compound of the present invention, which comprises reacting a methylating
reagent, such as- lithium hexamethyldisilazide with 3-(5-methylisoxazol-3-yl}-
6-
( 1H-1, 2, 3-triazol-5-yl) methyloxy-1, 2, 4-triazolo [3, 4-a] phthalazine.
The reaction is generally carried out in a solvent such as DMF, generally
at a temperature below 0°C with warming to about room temperature and
generally under an inert gas such as nitrogen. The reaction mixture is
generally
allowed to stand for 4-12 hours. The desired product is generally purified
from
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other reaction products by a conventional separation technique such as
preparative HPLC.
During any of the above synthetic sequences it may be necessary and/or
desirable to protect sensitive or reactive groups on any of the molecules
concerned. This may be achieved by means of conventional protecting groups,
such as those described in Protective Groups in Organic Chemistry, ed. J.F.W.
McOmie, Plenum Press, 19'73; and T.W. Greene & P.G.M. Wuts, Protective
Groups in Organic Synthesis, John Wiley & Sons, 1991. The protecting groups
may be removed at a convenient subsequent stage using methods known from
IO the art.
The compound in accordance with this invention potently inhibit the
binding of [3H]-ffumazenil to the benzodiazepine binding site of human GABAn
receptors containing the a5 subunit stably expressed in Ltk- cells.
Reagents
~ Phosphate buffered saline (PBS).
~ Assay buffer: 10 mM KHzP04, 100 mM KCI, pH 7.4 at room temperature.
~ [3HJ-Flumazenil (18 nM for al[i3y2 cells; 18 nM for a2[33y2 cells; 10 nM for
a3[33y2 cells; 10 nM for a5(33y2 cells) in assay buffer.
~ Flunitrazepam 100 uM in assay buffer.
~ Cells resuspended in assay buffer (1 tray to 10 ml).
Harvesting Cells
Supernatant is removed from cells. PBS (approximately 20 ml) is added.
The cells are scraped and placed in a 50 ml centrifuge tube. The procedure is
repeated with a further 10 ml of PBS to ensure that most of the cells are
removed. The cells are pelleted by centrifuging for 20 min at 3000 rpm in a
benchtop centrifuge, and then frozen if desired. The pellets are resuspended
in
10 ml of buffer per tray (25 cm x 25 cm) of cells.
Assay
Can be carried out in deep 96-well plates or in tubes. Each tube contains:
~ 300 ~1 of assay buffer.
~ 50 N.1 of [3H]-flumazenil (final concentration for al[i3y2: 1.8 nM; for
a2[33y2: 1.8
nM; for a3(33y2: 1.0 nM; for a5(33y2: 1.0 nM).
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~ 50 ul of buffer or solvent carrier (e.g. IO% DMSO) if compound is dissolved
in
10% DMSO (total); test compound or flunitrazepam (to determine non-specific
binding), 10 p,M final concentration.
~ 100 pl of cells.
Assays are incubated for 1 hour at 40°C, then filtered using
either a
Tomtec or Brandel cell harvester onto GFB filters followed by 3 x 3 ml washes
with ice cold assay buffer. Filters are dried and counted by liquid
scintillation
counting. Expected values for total binding are 3000-4000 dpm for total counts
and less than 200 dpm for non-specific binding if using liquid scintillation
counting, or 1500-2000 dpm for total counts and less than 200 dpm for non-
specific binding if counting with meltilex solid scintillant. Binding
parameters
are determined by non-linear Least squares regression analysis, from which the
inhibition constant K. can be calculated for the test compound.
The compound in accordance with this invention potently inhibits the
I5 binding of [3H]-ffumazenil to the benzodiazepine binding site of human
GABAA
receptors containing the a5 subunit stably expressed in Ltk- cells.
The compound of the accompanying Example was tested in the above
assay, and was found to possess a K; value for displacement of j3H]Ro 15-1788
from the a5 subunit of the human GABAn receptor of 100 nM or less.
The compound of the present invention has been shown to enhance
cognition in the rat water maze test (Morris, Learning and Motivation, 1981,
12, 239ffj. Further details of methodology for demonstrating that the present
compounds enhance cognition can be found in WO-A-9625948. This has been
demonstrated at a minimum effective dose of 0.3mg/kg at which the compound
of the present invention has 40% receptor occupancy. It has also been
demonstrated at a dose of 3mglkg.
The compound of the present invention can be made as described in
following Examples. Precise details of the reaction conditions, and obvious
modifications of the reaction procedure, are well within the capabilities of
the
skilled person.
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INTERMEDIATE 1
6-Chloro-3-(5-Methvlisoxazol-3-vD-1 2 4-triazolof3 4 a]nhthalazine -, _
a) 1-Chloro-4-hvdrazinophthalazine
1,4-Dichlorophthalazine (20.Og, 0.100 mol) was added to a boiling solution
of hydrazine monohydrate (37.3 ml, 0.765 mol) in ethanol (500 ml) and the
mixture heated at reflux for 0.5 h. The mixture was cooled to room temperature
and the solid collected by filtration and washed with ether. The material was
taken with n-butanol and ammonia solution (sp. gr. 0.91) and heated until the
solid dissolved. The organic layer was separated, evaporated in vacuo and the
residue azeotroped with xylene (x2) and dried in vacuo to give the title-
hydrazine
(11.5 g, 59°/), 3H NMR (250 MHz, døDMSO) 8 7.84 - 8.04 (3H, m, Ar-H},
8.20 (1H,
m, Ar-H); MS (ES+) m/e 194 [MH]+.
b) 5-Methvlisoxazole-3-carboxvlic acid
A mixture of acetonylacetone (lOg, 88 mmol) and nitric acid (sp. gr. 1.42) /
water (2:3) (50 ml) was cautiously brought to reflux under a stream of
nitrogen
and boiled for lh. The solution was cooled to room temperature and aged
overnight. The resultant solid was collected by filtration, washed with
chilled
water (2 x 7 ml) and hexane, and dried in vacuo to give the title-acid (4.4g,
40%),
1H NMR (CDCIs) b 2.50 (3H, d, J=0.8Hz, Me), 6.41 (1H, d, J=0.8Hz, Ar-H).
c) 6-Chloro-3-(5-Methvlisoxazol-3-vb-1 2 4-triazolof3 4 ainhthalazine
5-Methylisoxazole-3-carboxylic acid (5.24 g, 41.3 mmol), bis(2-oxo-3-
oxazolidinyl)phosphinic chloride (10.5 g, 41.2 mmol) and triethylamine (lL5
ml,
82.5 mmol) were added successively to a stirred suspension of 1-chloro-4-
hydrazinophthalazine (8.00 g, 41.2 mmol) in dichloromethane (11) at 0
°C under
nitrogen. The mixture was stirred at 0 °C for 2h and at room
temperature
overnight. The solvent was evaporated in vacuo, the residue triturated with
water and the solid filtered off, washed with hexane and dried in uacuo to
give
the ketohydrazine (11 g), MS (ES+) m/e 304 [MH]+. A solution of the
ketohydrazine (11 g) and triethylamine hydrochloride (2.2 g, 20% w/w) in
xylene
30, (500 ml) was heated at reflux for 3 h. The mixture was cooled to room -
temperature and the solvent evaporated in uacuo. The residue was dissolved in
dichloromethane, washed with water (x 2), dried (MgS04) and evaporated
in vacuo, and the solid recrystallised (dichloromethane/hexane) to give the
title-
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compound (6.8 g, 58%), 1H NMR (360MHz, CDCl3) 8 2.59 (3H, s, Me), 6.90 (1H, s,
Ar-H), 7.95 (1H, m, A.r-H), 8.0? (1H, m, Ar-H), 8.34 (1H, m, Ar-H), 8.78.(1H,
s,
Ar-H); MS (ES+) m/e 286 [MHJ+.
REFERENCE El AMPLE 1
3-(5-Methvlisoxazol-3-vl)-6-(2-nvridyDmethyloxy 1 2 4 triazoloj3 4
aJphthalazine
Sodium hydride (244 mg of a 60% dispersion in oil, 6.10 mmol) was added
to a stirred solution of 2-pyridylcarbinol (470 mg, 4.27 mmol) in DMF (60 ml)
at
room temperature under nitrogen and the mixture stirred for 0.25 h. After this
time, Intermediate 1 (1160 mg, 4.07 mmol) was added and the mixture stirred
for 2h. The solvent was removed in uacuo and the residue dissolved in
dichloromethane, washed with water (x2), dried (MgSOa) and evaporated
in vacuo. Flash chromatography on silica gel eluting with 3%
methanol/dichloromethane followed by recrystallisation
(dichloromethane/hexane) gave the title-product (640 mg, 44%), mp 234 - 236
°C;
'H NMR (360MHz, CDCIs) b 2.59 (3H, d, J =0.8Hz, Me), 5.77 (2H, s, CHz), 6.82
(1H, d, J=0.8Hz, A.r-H), 7.30 (1H, m, Ar-H), 7.74 - 7.85 (3H, m, Ar-H); 7.95
(1H,
m, Ar-H), 8.33 (1H, d, J=7.8Hz, Ar-H), 8.64 - 8.72 (2H, m, Ar-H}; MS (ES+) m/e
359 [MHJ+; Anal. Found. C, 62.93; H, 3.56; N, 22.94. CisHi4NsOz 0.05 (CHzCIz)
requires C, 63.10; H, 3.92; N, 23.1?%.
REFERENCE EXAMPLE 2
6-(6-Bromonvridin-2-vDmethvioxv 3 l5 methvlisoxazol 3 vl) 1 2 4 triazolo(3 4
a] phthalazine
The title-compound was prepared from Intermediate 1 and 2-
bromopyridine-6-methanol (Tetrahedron Lett., 1996, 50, 2537) following the
procedure given for Reference Example I. The product was isolated by addition
of water to the reaction mixture and the resulting precipitate was filtered
off.
Flash chromatography on silica gel, eluting with ethyl acetate, and
recrystallisation (ethyl acetate-methanol) gave the title phthalaxine, mp
247.5 -
249 °C; 'H NMR (360 MHz, CDCIs) 8 2.61 (3H, d, J = 0.7 Hz, Me), 5.?3
(2H, s,
CHz), 6.82 (1H, d, J = 0.7 Hz, Ar-H), 7.48 (1H, d, J = 7.8 Hz, Ar-H), 7.63
(1H, t,
J = 7.7 Hz, Ar-H), ?.76 (1H, d, J = 7.4 Hz, Ar-H), 7.84 (1H, t, J = 8.4 Hz, Ar-
H),
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7.98 (IH, t, J = 8.4 Hz, Ar-H), 8.31 (1H, d, J = 8.5 Hz, Ar-H), 8.70 (1H, d,
Ar-H);
MS (ES+) m/e 437, [MH]+; Anal. Found C, 52.27; H, 2.85; N, 19.14. C19H~3N6O2 -
Br. 0.1 (Hz0) requires C, 51.98; H, 3.03; N, 18:60%.
INTERMEDIATE 2
6-Hvdroxv-3-(5-Methvlisoxazol-3-vl)-1 2 4 triazolof3 4 alnhthalaz_ine
A solution of sodium hydroxide (0.67 g, I7 mmol) in water (7.5 ml) was
added to a stirred solution of Intermediate 1 (1.0 g, 3.5 mmol) in dioxane
(37.5
ml) and the mixture heated at reflux for 4 h. The solvent was evaporated
in uacuo and the residue partitioned between water and diethyl ether. The
aqueous layer was separated, washed with ether (x 1) and then acidified with
2N
hydrochloric acid until pH2 was attained. The solid which precipitated out of
solution was filtered off and the aqueous filtrate extracted with
dichloromethane
(x 3). The combined extracts were dried (MgS04) and evaporated in udcuo and
combined with the precipitate to give the title product (0.45 g, 48%), 1H NMR
(250 MHz, ds-DMSO) 8 2.58 (3H, d, J = 0.7 Hz, Me), 7.07 (1H, d, J = 0.9 Hz,
Ar-H), 7.94 (1H, m, Ar-H), 8.08 (1H, m, Ar-H), 8.24 (1H, d, J = 7.4 Hz, Ar-H),
8.54 (1H, d, J = 7:4 Hz, Ar-H), 13.32 (1H, br s, NH); MS (ES+) mle 268 [MH]+
REFERENCE EXAMPLE 3
3-(5-Methvlisoxazol-3-vl)-6-(1H-1 2 3-triazol 5 vDmethyloxy 1 2 4
triazolo f 3.4-alphthalazine
a) 5-Formvl-I-f2-(trimethvlsilvbethoxvlmethvl 1 2 3 triazole
n-Butyl lithium (6.8m1 of a 1.6M solution in hexanes, 10.9mmo1) was
added dropwise over 0.08h to a stirred solution of 1-[2-(trimethyl-
silyl)ethoxy]methyl-1,2,3-triazole (J. Heterocycl. Chem., 1992, 29, 1203)
(2.077g,
10.42mmo1) in THF (30m1) at -78°C under nitrogen. The solution was
allowed to
warm to -60°C aver 0.67h, then retooled to -78°C and DMF (0.9m1,
11.6mmo1)
added. The mixture was allowed to warm to room temperature and stirred for
16.5h. Saturated ammonium chloride solution (50m1) was added and the _
reaction mixture extracted with diethyl ether (3 x 80m1). The combined
ethereal
extrants were dried (MgS04), evaporated in uacuo, and the residue
chromatographed on silica gel, eluting with 30% ethyl acetate/hexane, to give
the
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title-triaxole (1.7138, 72%), 1H NMR (360 MHz, CDCIs) 8 0.01 (9H, s, MesSi),
0.92-0.99 (2H, m, CHz), 3.64-3.69 (2H, m, CHz), 6.05 (2H, s, CHa), 8.31
(lH;.s;
Ar-H), 10.12 (1H, s, CHO).
b) 5-Hvdroxvmethvl-1-f2-(trimethvlsilvDethoxvlrnethyl 1 2 3 triazole
Sodium borohydride (0.2848, 7.51mmo1) was added to a stirred solution of
the preceding triazole (1.7048, 7.495mmol) in methanol (8ml} at 0°C
under
nitrogen. The mixture was stirred at 0°C for 0.5h and at room
temperature for
O.Sh. Water was added and the mixture partitioned between dichloromethane
and saturated brine. The aqueous layer was separated and further extracted
with dichloromethane (x2). The combined organic layers were dried ((MgS09)
and evaporated in uacuo and the residue chromatographed on silica gel, eluting
with ?0% ethyl acetate/hexane, to give the title product (1.348, 78%), 1H NMR
(360 MHz, CDCla) 8 0.00 (9H, s, MesSi), 0.90-0.95 (2H, m, CHz), 3.58-3.63 (2H,
m,
CHz), 4.84 (2H, s, CHz), 5.80 (2H, s, CHz), 7.68 (1H, s, Ar-H).
c) 3-(5-Methvlisoxazol-3-vl)-6-11-f2-(trimethvlsilvDethoxvlmethvl 1 2 3
triazol-5-vllmethvloxv-12 4-triazolof3 4 a]'~n~hthalazine
The title-compound was prepared from Intermediate 1 and the preceding
alcohol following the procedure described for Example 10, 360 MHz (360 MHz,
CDCIs) 8 0.00 (9H, s, MesSi), 0.88-0.93 (2H, m, CHz), 2.63 (3H, s, Me), 3.61-
3.66
(2H, m, CHz), 5.92 (2H, s, CHz), 5.97 (2H, s, CHz), 6.89 (1H, s, Ar-H), 7.86
(1H,
m, Ar-H), 8.02 (1H, t, J = 7.7 Hz, Ar-H), 8.18 (1H, s, Ar-H), 8.23 (1H, d, J =
8.0
Hz, Ar-H), 8.76 (1H, d, J = 8.0 Hz, Ar-H); MS (ES+) m/e 479 [MH]+.
d) 3-(5-Methvlisoxazol-3-vl)-6-(1H 1 2 3 triazol 5 vbmethyloxv 1 2 4
triazolof3 4-a]nhthalazine
A mixture of the preceding product, ethanol (lOml) and 2N HCl (20m1)
was heated at 50°C for 15.25h. The solution was basified to pH 12 with
saturated sodium carbonate solution and the solvents evaporated in uacuo. The
residue was azeotroped with ethanol (x2) and chromatographed on silica gel,
eluting with 0-4% methanol/dichloromethane (gradient elution), to give the
title product, IH NMR (400 MHz, CDCIs) 8 2.65 (3H, s, Me), 5.73 (2H, s, CHz),
7.02 (1H, s, Ar-H), 7.87 (1H, t, J = 7.8 Hz, Ar-H), 7.99-8.03 (2H, m, 2 of Ar-
H),
8.24 (1H, d, J = 8.2 Hz, Ar-H) 8.72 (1H, d, J = 7.9 Hz, Ar-H); MS (ES+) m/e
349
~~+.
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EXAMPLE 1
3-(5-Methvlisoxazol-3-vl)-6-ll-methyl-1 2 3 triazol 5 vl)methyloxy 1 2 4
triazolof3 4-alnhthalazine 3-(5-methvlieoxazol 3 vl) 6 (2 methyl 1 2 3 triazol
4
yDmethyloxv-1 2 4-triazolof3 4-alnhthalazine and 3 (5 methylisoxazol 3 vl) 6
(1
methyl-1.2,3-triazol-4-vDmethvloxv-I 2 4-triazolof3 4 aln~hthalazine
Lithium hexamethyldisilazide (1.63m1 of a 1M solution in THF,
1.63mmol) was added dropwise to a stirred solution of 3-(5-methylisoxazol-3-
yl)-
6-(1H-1,2,3-triazol-5-yl)methyloxy-1,2,4-triazolo[3,4-a]phthalazine (241mg,
0.626mmo1) prepared as in Reference Example 3 in DMF (50m1) at -31°C
under
nitrogen. The mixture was warmed to -23°C over 1.5h, methyl iodide
(O.lOml,
l.6mmo1) added dropwise and the reaction mixture allowed to warm to room
temperature overnight. Water was added and the solvent evaporated in vacuo.
The residue was partitioned between dichloromethane and water and the
aqueous phase separated and re-extracted with dichloromethane (xl). The
combined organic extrants were washed with brine (xl), dried (MgS04) and
evaporated in vacuo . Chromatography of the residue on silica gel, eluting
with
0-5% methanol/dichloromethane (gradient elution), followed by preparative
HPLC (YMC Sil column, 250 x 20mm) eluting with 5% methanol/1-chlorobutane,
separated the triazole isomers:
Least polar isomer (HPLC solvent system): 3-(5-methvlisoxazol-3-yD-6-(2-
methvl-12 3-triazol-4-vl)methvloxv 12 4 triazolo[3 4 a]phthalazine 1H NMR
(400 MHz, CDCIa) 8 2.59 (3H, s, Me), 4.21 (3H, s, Me), 5.73 (2H, s, CHz), 6.89
(1H, s, Ar-H), 7.79 (1H, m, Ar-H), 7.94 (1H, m, Ar-H), 8.10 (1H, s, Ar-H),
8.22
(1H, d, J = 8.0 Hz, Ar-H), 8.67 (1H, d, J = 8.0 Hz, Ar-H); MS (ES+) mle 363
[MH]+.
Intermediate polarity isomer: 3-l5-methvlisoxazol-3-vD-6-(1-methyl 1 2 3
triazol
4-vl)methvloxv-1 2 4-triazolof3 4-alDhthalazine 1H NMR (400MHz, CDCls) 8 2.60
(3H, s, Me), 4.09 (3H, s, Me), 5.78 (2H, s, CHz), 6.90 (1H, d, J = 0.8 Hz, Ar-
H),
7.80 (1H, m, Ar-H), 7.94 (1H, m, Ar-H), 8.25 (1H, d, J = 8.0 Hz, Ar-H), 8.65
(1H,
d, J = 8.0 Hz, Ar-H), 8.73 (1H, s, Ar-H); MS (ES+) mle 363 [MH]+.
Most polar isomer (HPLC solvent system): 3-(5-methvlisoxazol-3-vl)-6-(1-
methv_1-
1.2.3-triazol-5-vl)methvloxy-1 2 4-triazolof3 4 alnhthalazine 1H NMR (400
MHz, CDCIa) 8 2.56 (3H, s, Me), 4.19 (3H, s, Me), 5.?6 (2H, s, CHz), 6.82 (1H,
s,
CA 02317416 2000-07-10
WO 99143677 - 1I - PCTIGB99/00485
Ar-H), 7.80 (1H, m, Ar-H), 7.96 (1H, m, Ar-H), 8.04 (1H, s, Ar-H), 8.12 (1H,
d,
J = 8.8 Hz, Ar-H), 8.67 (1H, d, J = 8.0 Hz, Ar-H); MS (ES+) m/e 363 [MIi]+. _
_
