Patent Application
20080096884
The various aspects of the invention will now be described by reference to the following examples. These examples are merely illustrative and are not to be construed as a limitation of the scope of the present invention. In this section, “intermediates” represent syntheses of intermediate compounds intended for use in the synthesis of the ‘examples’
HPLC high performance liquid chromatography
NMR nuclear magnetic resonance
LC/MS liquid chromatography/mass spectroscopy
TLC thin layer chromatography
SPE solid phase extraction column. Unless otherwise specified the solid phase will be silica gel. Aminopropyl SPE refers to a silica SPE column with aminopropyl residues immobilised on the solid phase (eg. IST Isolute™ columns). It is thought that compounds isolated by SPE are free bases.
SCX solid phase extraction (SPE) column with benzene sulfonic acid residues immobilised on the solid phase (eg. IST Isolute™ columns). When eluting with ammonia/ methanol, it is thought that compounds isolated by SCX are free bases.
Waters ZQ mass spectrometer operating in positive ion electrospray mode, mass range 100-1000 amu.
UV wavelength: 215-330 nM
Column: 3.3 cm×4.6 mm ID, 3 μm ABZ+PLUS
Flow Rate: 3 ml/min
Injection Volume: 5 μl
Solvent A: 95% acetonitrile+0.05% formic acid
Solvent B: 0.1% formic acid+10 mM ammonium acetate
Gradient: Mixtures of Solvent A and Solvent B are used according to the following gradient profiles (expressed as % Solvent A in the mixture): 0% A/0.7 min, 0-100% A/3.5 min, 100% A/1.1 min, 100-0% A/0.2 min
The preparative column used was a Supelcosil ABZplus (10 cm×2.12 cm internal diameter; particle size 5 μm)
UV detection wavelength: 200-320 nM
Flow rate: 20 ml/min
Injection Volume: 0.5 ml
Solvent A: 0.1% formic acid
Solvent B: 95% acetonitrile+0.05% formic acid
Gradient systems: mixtures of Solvent A and Solvent B are used according to a choice of 5 generic gradient profiles (expressed as % Solvent B in the mixture), ranging from a start of 0 to 50% Solvent B, with all finishing at 100% Solvent B to ensure total elution.
It is thought that compounds isolated by this method are free bases, unless the R1 or R3 groups contain basic moieties, in which case formate salts may be formed.
The preparative column used was a Supelcosil ABZplus (10 cm×2.12 cm internal diameter; particle size 5 μm)
UV detection wavelength: 200-320 nM
Flow rate: 20 ml/min
Injection Volume: 0.5 ml
Solvent A: water+0.1% trifluoroacetic acid
Solvent B: acetonitrile+0.1% trifluoroacetic acid
Gradient systems: mixtures of Solvent A and Solvent B are used according to a choice of 5 generic gradient profiles (expressed as % Solvent B in the mixture), ranging from a start of 0 to 50% Solvent B, with all finishing at 100% Solvent B to ensure total elution.
It is thought that compounds isolated by this method are trifluoroacetate salts.
It is thought that compounds isolated by this method from reactions involving displacement of a 4-chloroquinoline intermediate with an amine of formula R1R2NH are hydrochloride salts.
This refers to a Whatman PTFE filter medium (frit), pore size 5.0 μm, housed in a polypropylene tube.
Reference to column chromatography, SPE and preparative HPLC purification includes evaporation of the product containing fractions to dryness by an appropriate method.
‘880 Ammonia’ or ‘0.880 ammonia’ refers to concentrated aqueous ammonia (specific gravity 0.880).
All reagents not detailed in the text below are commercially available from established suppliers such as Sigma-Aldrich.
Intermediate 1. Diethyl ({4-(1-piperidinylsulfonyl)phenyl]amino}methylidene) propanedioate
4-(1-Piperidinylsulfonyl)aniline (0.20 g) (available from Maybridge International) and diethyl (ethoxymethylene)malonate (0.18 g) (available from Aldrich) were heated at 150° C. under 150 W microwave irradiation for 15 mins. The mixture was diluted with cyclohexane, filtered and the residue dried at 40° C. in vacuo to give the title compound as a pale pink solid (0.284 g).
Intermediate 2. Ethyl 4-oxo-6-(1-piperidinylsulfonyl)-1,4-dihydro-3-quinolinecarboxylate
Intermediate 1 (0.284 g) was suspended in diphenyl ether (15 ml) and heated at 250° C. for 2 h. After cooling, the mixture was diluted with cyclohexane (50 ml) and the resulting precipitate filtered off and dried in vacuo to give the title compound as a brown solid (0.138 g).
LC/MS Rt 2.68 min m/z 365 [MH+]
Intermediate 3. 4-Oxo-6-(1-piperidinylsulfonyl)-1,4-dihydro-3-quinolinecarboxylic acid
Intermediate 2 (0.138 g) was dissolved in ethanol (2 ml) and 2 M sodium hydroxide (2ml) and the mixture heated under reflux for 3 h. After cooling the solvent was removed under a stream of nitrogen and the residue dissolved in water (2 ml) and extracted with ethyl acetate (2×4 ml). The aqueous layer was acidified to pH 6.0 using 2M hydrochloric acid, and the resulting precipitate removed by filtration and dried in vacuo at 40° C. to give the title compound (0.052 g).
LC/MS Rt 2.83 min m/z 337 [MH+]
Intermediate 4. 4-Chloro-6-(1-piperidinylsulfonyl)-3-quinolinecarboxamide
Intermediate 3 (0.051 g) was suspended in thionyl chloride (4 ml) and treated with N,N-dimethylformamide (4 drops), and the mixture heated at 80° C. for 18 h. The solvent was removed in vacuo and the residue azeotroped with toluene (5 ml). The resulting solid was added to 880 ammonia (4 ml) and the mixture stirred at room temperature for 3 h. The solid was removed by filtration to give the title compound as a brown solid (0.011 g).
LC/MS Rt 2.63 min m/z 354 [MH+]
Intermediate 5. Diethyl {[(4-iodophenyl)amino]methylidene}propanedioate
A mixture of 4-iodoaniline (208 g) (available from Aldrich) and diethyl (ethoxymethylene)malonate (210 ml) (available from Aldrich) was heated to 100° C. The mixture set solid at ca. 60° C., and was removed from heating and broken up. Heating was continued at 100° C. for 1 h, and the solid was collected, washed with cyclohexane (1000 ml) and ethanol (2×500 ml), and dried in vacuo at 40° C. overnight to give the title compound as a white solid (356 g).
LC/MS Rt 3.57 min m/z 390 [MH+].
Intermediate 6. Ethyl 6-iodo4-oxo-1 4-dihydro-3-quinolinecarboxylate
Diphenyl ether (170 ml) was heated to reflux and intermediate 5 (30 g) was gradually added down an air condenser. Once all the reagent had been added the mixture was heated under reflux for a further 30 min. The mixture was then cooled and isohexane (200 ml) was added. The solid formed was collected by filtration to give the title compound (19.2 g).
NMR: (d-6 DMSO) δ 8.58 (1H,s), 8.42(1H,d), 7.99 (1H,dd), 7.44(1H,d), 4.21(2H,q), 1.28 (3H,t).
Intermediate 7. 6-Iodo-4-oxo-1,4-dihydro-3-quinolinecarboxylic acid
Sodium hydroxide (9.8 g) was dissolved in water (61 ml) and ethanol (30 ml) was added. The resultant solution was added to intermediate 6 (10.0 g), and the mixture was heated under reflux for 60 min with stirring under nitrogen. Concentrated hydrochloric acid was added, giving a white precipitate. After stirring for 16 h, the precipitate was filtered off, washed with water and dried in vacuo to give the title compound as a white solid (8.15 g).
LC/MS Rt 3.01 min m/z 316 [MH+].
Intermediate 8. 4-Chloro-6-iodo-3-quinolinecarboxamide
Intermediate 7 (8.1 g) was added portionwise to stirred thionyl chloride (60 ml). N,N-dimethylformamide (3 drops) was added and the mixture was heated under reflux with stirring under nitrogen for 1.75 h. The excess thionyl chloride was evaporated in vacuo and the residue was azeotroped with toluene (2×50 ml). The resulting pale yellow solid was added portionwise to stirred 880 ammonia (250 ml), and the mixture stirred at room temperature for 1.5 h. The solid was filtered off, washed with water and dried in vacuo at 60° C. for 16 h to give the title compound as a white solid (7.94 g).
LC/MS Rt 2.72 min m/z 332 [MH+].
Intermediate 9. 4-Chloro-6-[(1,1-dimethylethyl)thio]-3-guinoline carboxamide
To a stirred mixture of intermediate 8 (14.7 g) and tetrakistriphenylphosphine palladium (0) (1.02 g) in toluene (250 ml) under nitrogen was added a solution of (tert-butylsulphanyl)tributyltin (JACS 2002, 124, 4874) (20.1 g) in toluene (50 ml), and the mixture was heated under reflux for 1 h. The mixture was cooled to room temperature, partitioned between 5% potassium fluoride solution (1000 ml) and diethyl ether (500 ml) and the organic solvent evaporated in vacuo. The solid obtained was triturated with diethyl ether and filtered to give the title compound as a pale orange solid (9.47 g). The filtrate was evaporated in vacuo. Purification by chromatography on silica gel, eluting with diethyl ether then ethyl acetate, gave further title compound as an orange solid (2.97 g; total yield 12.4 g).
LC/MS Rt 3.04 min m/z 295 [MH+]
Intermediate 10. 6,6′-Dithiobis(4-chloro-3-guinolinecarboxamide)
Intermediate 9 (12.3 g) was dissolved in trifluoroacetic acid (200 ml), phenyl sulphoxide (21.2 g) added, and the mixture cooled to 0° C. Methyltrichlorosilane (49 ml) was added over 10 mins, and the mixture stirred for 1 h. The mixture was evaporated in vacuo, the residue triturated with diethyl ether (250 ml), and the solvent decanted off. The residue was triturated twice more with diethyl ether (200 ml) and the solid filtered off to give the title compound as a pale yellow solid (10.5 g).
LC/MS Rt 2.87 min m/z 475 [MH+]
Similarly prepared using 4-iodo-2-methylaniline Instead of 4-iodoaniline (as in the preparation of Intermediate 5) was:
Intermediate 10a. 6,6′-Dithiobis(4-chloro-8-methyl-3-guinolinecarboxamide)
LC/MS Rt 3.50 min m/z 503 [MH+]
Intermediate 11. 3-(Aminocarbonyl)-4-chloro-6-guinolinesulfonyl chloride
Chlorine was bubbled through a suspension of intermediate 10 (0.20 g) in acetic acid (4 ml) and water (1 ml) for 5 min, giving a yellow solution. The mixture was partitioned between water (50 ml) and diethyl ether (50 ml) and the organic layer dried (Na2SO4) and concentrated in vacuo to give the title compound as a pale yellow solid (0.248 g).
LC/MS Rt 2.63 min m/z 305 [MH+]
Intermediate 12. 4-Chloro-6-(4-morpholinylsulfonyl)-3-guinolinecarboxamide
A solution of intermediate 11 (0.88 g) in dichloromethane (10 ml) and N,N-dimethylformamide (5 ml) was added to a solution of morpholine (0.131 ml) and N,N-diisopropylethylamine (1.31 ml) in dichloromethane (30 ml) at 0-5° C. The mixture was allowed to warm to 20° C. over 18 h, diluted with dichloromethane (150 ml), and extracted with 1M hydrochloric acid (100 ml) followed by saturated aqueous sodium bicarbonate solution (100 ml). The organic layer was dried (Na2SO4) and evaporated in vacuo to give the title compound as a brown gum (0.571 g).
LC/MS Rt 2.22 min m/z 356 [MH+]
Similarly prepared from intermediate 11 were the following:
Intermediate 25. 1.1-Dimethylethyl 4-(chlorocarbonyl)-1-piperazinecarboxylate
A solution of 1,1-dimethylethyl 1-piperazinecarboxylate (13.0 g) (available from Aldrich) and pyridine (11.2 ml) in dichloromethane (30 ml) was added dropwise to a solution of triphosgene (8.3 g) in dichloromethane (60 ml) at 0-5° C. The cooling bath was removed and the mixture warmed to room temperature over 30 min. The mixture was quenched by the dropwise addition of 1M hydrochloric acid (50 ml). The organic layer was separated and washed successively with 1M hydrochloric acid (40 ml), water (40 ml) and saturated sodium chloride solution (40 ml), dried (Na2SO4) and evaporated in vacuo to give the title compound as a yellow solid (16.0 g).
1HNMR (CDCl3) δ 3.71 (2H,m,CH2), 3.62 (2H,m,CH2), 3.5 (4H,m,2xCH2),1.5 (9H,s,3xCH3).
Intermediate 26. 1,1-Dimethylethyl 4-[(dimethylamino)carbonyl]-1-piperazinecarboxylate
To a solution of dimethylamine hydrochloride (0.15 g) (available from Aldrich) in dichloromethane (5 ml) was added triethylamine (0.305 g) and the mixture stirred for 10 min, after which intermediate 25 (0.3 g) was added. The mixture was heated under reflux for 3 hr, cooled, diluted with dichloromethane (20 ml) and washed with water (20 ml). The organic layer was dried and evaporated in vacuo; the residue was loaded in methanol onto a sulphonic acid ion exchange cartridge (Isolute SCX), and the cartridge was eluted with methanol. Evaporation of the solvent gave the title compound as a white solid (0.276 g).
1HNMR (CDCl3) δ 3.45 (4H,m,CH2), 3.2 (4H,m,2xCH2), 2.85 (6H,s,2xCH3), 1.55 (9H,s,3xCH3).
Intermediate 27. N,N-dimethyl-1-piperazinecarboxamide
To intermediate 26 (0.27 g) was added 4M hydrogen chloride in 1,4 dioxane (10 ml); after stirring for 3 h the solvent was evaporated in vacuo to give the title compound as a white solid (0.238 g).
1HNMR (MeOD) δ 3.5 4 (H,m,CH2), 3.3 (4H,m,2xCH2), 2.95 (6H,s,2xCH3), 3.35 (1H,m,NH)
Intermediate 28. 4-Chloro-8-methyl-6-(4-morpholinylsulfonyl)-3-guinolinecarboxamide
Chlorine was bubbled through a suspension of intermediate 10a (3.0 g) in acetic acid (40 ml) and water (10 ml) for 4 min. The mixture was partitioned between water (300 ml) and diethyl ether (300 ml) and the organic layer dried (MgSO4) and concentrated in vacuo. The residue was triturated with toluene (75 ml) and the solvent removed in vacuo to give a yellow solid (2.7 g). The yellow solid (1 g) in dichloromethane (3 ml) and N,N-dimethylformamide (0.5 ml) was added to a solution of morpholine (0.272 g) and N,N-diisopropylethylamine (1 ml) in dichloromethane (15 ml) at 0° C. The mixture was stirred at 0° C. for 2 h and then allowed to warm to room temperature over 3 h. The mixture was partitioned between saturated aqueous sodium bicarbonate solution (40 ml) and dichloromethane (40 ml). The organic layer was collected, dried (MgSO4) and the solvent removed in vacuo. Purification by chromatography on silica gel, eluting with 30% cyclohexane in ethyl acetate gave the impure title compound as a fawn foam (0.6 g).
LC/MS Rt 2.52 min m/z 370 [MH+]; major by product LC/MS Rt 2.70 min m/z 455 [MH+]
Similarly prepared from intermediate 10a and 1-acetylpiperazine (Aldrich) was the following:
Intermediate 29. 6-[(4-Acetyl-1-piperazinyl)sulfonyl]-4-chloro-8-methyl-3-quinolinecarboxamide
LC/MS Rt 2.41 min m/z 411 [MH+]
Intermediate 30. 4-Chloro-6-({[2-(4-morpholinyl)ethyl]amino}sulfonyl)-3-quinolinecarboxamide
Chlorine was bubbled through a vigourously stirred suspension of intermediate 10 (2.5 g) in acetic acid (40 ml) and water (10 ml) at room temperature for 10 min. The mixture was partitioned between water (300 ml) and diethyl ether (2×300 ml) and the organic layers washed with brine, dried (MgSO4) and concentrated in vacuo. The residue was triturated with toluene (2×150 ml) and the solvent removed in vacuo to give the sulphonyl chloride intermediate as a yellow solid (3.3 g). The yellow solid was dissolved in a mixture of dichloromethane (100 ml) and N,N-dimethylformamide (11 ml), and an aliquot (11.1 ml) of this solution was added to a solution of [2-(4-morpholinyl)ethyl]amine (Aldrich, 0.136 g) and N,N-diisopropylethylamine (0.367 ml) in dichloromethane (2 ml) at 0° C. The mixture was stirred at 0° C. for 2 h and then allowed to warm to room temperature overnight. The mixture was partitioned between saturated aqueous sodium bicarbonate solution (20 ml) and dichloromethane (10 ml). The organic layer was separated using a hydrophobic frit, and the solvent removed in vacuo to give the title compound as a brown gum (0.334 g).
LC/MS Rt 1.77 min m/z 399 [MH+]
Similarly prepared from intermediate 10 were the following:
Intermediate 33. 4-Chloro-6-[(methylamino)sulfonyl]-3-quinolinecarboxamide
Chlorine was bubbled through a vigourously stirred suspension of intermediate 10 (0.1 g) in acetic acid (4 ml) and water (1 ml) at room temperature for 2 min. The mixture was partitioned between water (100 ml) and diethyl ether (3×50 ml) and the organic layers washed with brine, dried (MgSO4) and concentrated in vacuo. The residue was triturated with toluene (2×15 ml) and the solvent removed in vacuo to give the sulphonyl chloride intermediate as an orange gum (0.127 g). The orange gum was dissolved in N,N-dimethylformamide (2.6 ml), and an aliquot (1.3 ml) of this solution was cooled to 0° C. Methylamine hydrochloride (Aldrich, 0.0074 g) and N,N-diisopropylethylamine (0.058 ml) were added, and the mixture was allowed to warm to room temperature with stirring overnight (18 h). The mixture was applied directly to a solid phase extracton cartridge (Isolute, aminopropyl solid phase, 10 g), and eluted sequentially with chloroform, ether, ethyl acetate, acetone and methanol. The acetone and methanol fractions were evaporated to give the title compound (0.0109 g).
LC/MS Rt 2.04 min m/z 300 [MH+]
Intermediate 4 (0.011 g) was suspended in acetonitrile (2 ml), 3-methoxyaniline (0.004 g) (available from Aldrich) was added and the mixture heated at 70° C. for 5 h. The mixture was cooled to room temperature, and the precipitate filtered off, washed with acetonitrile and dried to give the title compound (0.008 g).
LC/MS Rt 2.75 min m/z 441 [MH+]
Similarly prepared from the intermediate numbers shown in the table were the following:
Intermediate 28 (0.050 g) was suspended in acetonitrile (2 ml), 4-fluoro-3-(methyloxy)aniline (0.025 g) (available from Aldrich) was added and the mixture heated at 80° C. for 16 h. The mixture was cooled to room temperature and the solvent blown off under a stream of nitrogen. Purification by mass directed HPLC gave a yellow oil. This was loaded onto an SPE cartridge (1 g Varian Bond Elut, aminopropyl solid phase) and eluted with methanol to give the title compound as a yellow solid (0.018 g).
LC/MS Rt 2.58 min m/z 475 [MH+]
Similarly prepared from the intermediate numbers shown in the table were the following:
4-Fluoro-3-methoxyaniline (Apollo-Chem, 0.0085 g) was added to intermediate 30 (0.021 g) in ethanol (3 ml), pyridine hydrochloride 0.012 g) was added, and the mixture was heated under reflux for 5 h. The solvent was evaporated to give a brown gum (0.033 g), which was purified by mass directed preparative HPLC (Method A); 2N hydrochloric acid (1 ml) was added to the product fractions, and the solvents evaporated to give the title compound (0.0067 g).
LC/MS Rt 1.91 min m/z 504 [MH+]
To intermediate 31 (0.042 g) in ethanol (3 ml) was added 2,3-dihydro-1-benzofuran-4-amine (Journal of Heterocyclic Chemistry (1980), 17(6), 1333-5, 0.016 g) and concentrated hydrochloric acid (0.1 ml), and the mixture was heated under reflux for 3 h. The solvent was evaporated to give the crude product (0.070 g), which was purified by mass directed HPLC (Method A); 2N hydrochloric acid (0.5 ml) was added to the product fractions, and the solvents evaporated to give the title compound (0.0041 g).
LC/MS Rt 1.89min m/z 496 [MH+]
Similarly prepared from intermediate 32 and 4-fluoro-3-methoxyaniline (Apollo-Chem) (except that no hydrochloric acid was added to the preparative HPLC fractions) was:
LC/MS Rt 1.79 min m/z 488 [MH+]
To a solution of intermediate 33 (0.011 g) in acetonitrile (2 ml) and N,N-dimethylformamide (1.5 ml) was added 4-fluoro-3-methoxyaniline (Apollo-Chem, 0.007 g), and the mixture was heated at 80° with stirring under nitrogen for 18 h. The solvents were evaporated to give a brown gum, which was purified by mass directed preparative HPLC (Method A); 2N hydrochloric acid (0.5 ml) was added to the product fractions, and the solvents evaporated to give the title compound as a pale yellow solid (0.0058 g).
LC/MS Rt 2.17 min m/z 405 [MH+]
| Number | Date | Country | Kind |
|---|---|---|---|
| 0322722.0 | Sep 2003 | GB | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/EP04/10844 | 9/23/2004 | WO | 00 | 2/6/2007 |
