PROCESS FOR PREPARING 1-ARYL-4-OXOPYRROLO[3,2-c]QUINOLINE DERIVATIVES

Abstract: The present invention relates to a process for preparing 1-aryl-4-oxopyrrolo[3,2-c]quinoline derivatives through reaction of 4-oxofuro[3,2-c]quinoline compounds with aniline compounds under mild conditions in a single step, wherein 1-aryl-4-oxopyrrolo[3,2-c]quinoline derivatives having various substituents may be prepared in high yield, so that the 1-aryl-4-oxopyrrolo[3,2-c]quinoline derivatives may be utilized as an intermediate for producing a reversible inhibitor of gastric acid secretion.

Description: PROCESS FOR PREPARING l-ARYL-4-OXOPYRROLO[3,2-c]QUINOLINE DERIVATIVES Field of the invention The present invention relates to a process for preparing l-aryl-4-oxopyrrolo[3,2-c]quinoline derivatives and, more particularly, to a process for preparing 1-aryl-4-oxopyrrolo [3 , 2-c] quinoline derivatives represented by structure I -which is prepared through the reaction of 4-oxofuro[3,2-c] .quinolines with anilines represented by structure III . The formulae I, II and III are as follows: (ID wherein, R 1 may be same or different from R 2 which are respectively hydrogen, lower alkyl group of C 1 -C 4/ lower alkoxy group of Cj-C 4 , lower alkylthio group of C,-C 4 , lower haloalkoxy group of C x -C 4 , trifluoromethyl group, hydroxyalkoxy group of C j -C 4 , halogen, or hydroxy group; and R 3 may be same or different from R 4 which are respectively hydrogen, lower alkyl group of C 1 -C 4 , lower alkoxy group of Ci-C,, lower alkylthio group of Cj-C,, lower haloalkyl group of Cj-C 4 , trifluoromethyl group, hydroxy group, amino group, or halogen. The l-aryl-4-oxopyrrolo [3 , 2-c] guinoline derivatives which are prepared according to the present invention are used as intermediates for preparing compounds as represented by structure IV for suppressing gastric acid secretion and many studies have been carried out to prepare the intermediate so far [European Patent Application No. 90-313398.1; European Patent Application No. 88-306583.1; J. Med. Chem., 1990, 33, 527; J. Med. Chem., 1992, 35, 1845] . (I) (IV) The present invention is to provide a process for preparing compounds as represented by the above structure I which are intermediates in preparation of compounds as represented by the above structure IV which are useful as represser of the gastric acid secretion. The present invention is to provide a process for preparing compounds as represented by the above formula IV by using the l-aryl-4-oxopyrrolo [3 , 2-c] quinoline derivatives which can be prepared in a single reaction step from 4-oxofuro [3 , 2-c] quinoline with anilines III. Prior Art European Patent Application No . 88-306583.1 and an article [J. Med. Chem., 1992, 35, 1845] disclose a process for preparing 1-aryl-4-oxopyrrolo [3 , 2-c] quinoline derivatives as represented by the above structure I, which may be summarized as follows: OEt According to the prior art, the 1-aryl-4-oxo pyrrolo [3, 2-c]quinoline derivatives I is prepared through reaction of (Et0 2 C) 2 CHCH 2 CH 2 OEt with anilines aε starting material. This method has, however, disadvantages that yield is low while producing the compound I and a large amount of the compounds VI is formed as a by-product . Further, the method has an inherent limitation that substituents are limited to R 1 initially present in the starting anilines, and it is impossible to prepare derivatives which has variable substituents. On the other hand, an article [J. Med. Chem., 1992, 35, 1845] discloses a process for preparing compounds I having substituents R 1 , R 2 , R 3 and R 4 , which may be summarized as follows: NH, (Et0 2 C) 2 CHCH 2 CH 2 OEt According to the above method, 4-oxofuro [3 , 2-c] quinolines are chlorinated with P0C1 3 and subject to hydrolysis to obtain compounds VII, so that l-aryl-4- oxopyrrolo [3, 2-c] quinoline derivatives I having the substituents R 1 , R 2 , R 3 and R 4 through the reaction of various anilines with the compounds VII. The method has still disadvantages that a great amount of very toxic P0C1 3 has to be used as a reaction reagent and yields are relatively low about 50-70% in each reaction steps. Further, the compound I was obtained in mere prepared 20% yield due to the rather lengthy reaction steps from the compound II. Therefore, the present inventors have developed a novel process to resolve the disadvantages of prior art and to prepare the compounds IV with high biological activity and various substituents through environmentally friendly and simple steps . As a result, the quinoline compound IV may be prepared in a high yield by using 1-aryl-4-oxopyrrolo [3 , 2-c]quinoline derivatives which may be prepared conveniently in a high yield in such a manner that 4-oxofuro13, 2-c]quinolines II as starting material are reacted with various anilines as reactant in a single step. SUMMARY OF THE INVENTION The present invention has an objective to provide a process for preparing l-aryl-4-oxopyrrolo [3, 2-c]quinoline derivatives I through a single step to react 4-oxofuro[3, 2-c] qumolines II as a starting material with aniline III The present invention has another objective to provide a process for preparing quinoline compounds IV by using the l-aryl-4-oxopyrrolo [3, 2-c]quinoline derivatives . According to the present invention, rhe above objective can be achieved by a process for preparing l-aryl-4-oxopyrrolo [3, 2-c] quinoline derivatives by reacting 4-oxofuro [3 , 2-c]qumolines with anilines under a gentle condition m a single step, wherein l-aryi-4- oxopyrrolo[3, 2 -c] quinoline derivatives having various substituents may be obtained m high yield, so that the 1-aryl-4-oxopyrrolo[3, 2-c] quinoline derivatives maybe utilized as intermediate for producing a reversible inhibitor of gastric acid secretion. DETAILED DESCRIPTION OF THE INVENTION The present invention will now be described in detail with reference to the schemes showing embodiments thereof The present invention relates to a method of preparing l-aryl-4 -oxopyrrolo [3 , 2-c] quinoline derivatives represented by structure I which are useful intermediate for compounds represented by structure IV with high biological activity, wherein the l-aryl-4- oxopyrrolo [3, 2-c]quinoline derivatives are prepared by the reaction of aniline compounds represented by structure III with 4-oxofuro [3 , 2-c] quinolines represented by structure II as starting material. According to the present invention, the 1-ary1-4-oxopyrrolo [3, 2-c] quinoline derivatives with various substituents R 1 , R 2 , R 3 and R 4 may oe prepared in higher than 70% of yield. (H) In the formulae I, II and III, substituents R 1 , R 2 , R 3 and R 4 are defined as above. The preparation of substituted quinoline compounds, 4-oxofuro[3 , 2-c] quinoline derivatives II used as starting material are well described in the 5 prior art [1, J. Chem. Sec, 1955, 4284; 2. J. Med. Chem. , 1992, 35, 1845] . According to the present invention, solvent is selected from those such as dimethylformamide, dimethyl sulfoxide, diphenyl ether, xylene and the like, or 10 alcoholic solvents such as butyl alcohol, phenol, ethylene glycol monomethyl ether and the like. Preferably, the solvent is selected from alcoholic solvents of which boiling point is 150-280°C, such as phenol, ethylene glycol, diethylene glycol or 15. polyethylene glycol . The process for preparing 1-aryl-4-oxopyrrolo [3, 2-c] quinoline derivatives according to the present invention is preferably performed under inert atmosphere, such as argon or nitrogen. 20 As a reaction catalyst, p-toluenesulfonic acid and p-toluenesulfonic acid pyridine salt (PPTS) may be used. Reaction temperature is preferably maintained at 70-300°C, and more preferably, 150-280°C, and 25 reaction time is preferably 7-20 hours. One to three equivalents of the anilines, as represented by structure III, is effective for preparation 4-oxopyrrolo [3 , 2-c] quinolines as represented by structure II. Typical examples of the 1-aryl-4-oxopyrrolo(3, 2 -c]quinoline derivatives as represented by structure I according to the present invention are shown in table 1, as follows: <table 1> The l-aryl-4-oxopyrrolo[3, 2-c] quinoline derivatives I which is prepared as above can be used to prepare the compound IV as a reversible inhibitor of the gastric acid secretion through the publicly known method (J. Med. Chem., 1992, 35, 1845) ( X) While the invention has been described by reference to specific examples chosen for purposes of illustration, it should be apparent that the present invention be not limited by the specific disclosure herein and numerous modifications could be made thereto by those skilled in the art without departing from the basic concept and scope of the invention. <Example l> Preparation of 1- (2-methylphenyl) -4-oxo-6- methyl-2, 3,4, 5-tetrahydropyrrolo [3 , 2-c]quinoline 4-Oxo-6-methyl-2, 3-dihydrofuro [3, 2-c]quinoline (201 mg, 1.0 mmol) was dissolved in 10ml of diethylene glycol in a pressure tube and 2-methylaniline (267μl, 2.5mmol) was added under nitrogen. The reaction mixture was heated at 250°C for 15 hours. The reaction mixture was diluted with 20ml of saline and the aqueous layer was extracted with methylene chloride (15ml x 3) . After washing with water (15ml x 3) , the organic layer was dried with anhydrous magnesium sulfate and filtered, and concentrated under reduced pressure. The residue was purified with ethyl acetate as eluent by silica gel chromatography to obtain 237mg of a desired compound as solid in 82% of yield. mp: 171-173°C X H NMR(CDC1 3 , 200MHz) : δ 2.31(s, 3H) , 2.44(s, 3H) , 3.05-3.38(m, 2H) , 3.76(q, IH) , 4.05-4.23(m, IH) , 6.55-6.75(m, 2H) , 7.05-7.39(m, 5H) , 8.74(brs, IH) m/e: 290 (M * ) <Example 2> Preparation of 1- (2-methoxyphenyl) -4-oxo-6- methyl-2 ,3,4, 5-tetrahydropyrrolo [3 , 2-c] quinoline 4-Oxo-6-methyl-2, 3-dihydrofuro[3, 2 -c] quinoline (201mg, i.Ommol) was dissolved in 10ml of diethylene glycol and 2-methoxyaniline (282μl, 2.5mmol) was added under nitrogen. The reaction mixture was heated at 250°C for 15 hours. The reaction mixture was diluted with 20ml of salt water and the aqueous layer was extracted with methylene chloride (15ml x 3) . After washing with water (15ml x 3) , the organic layer was dried by anhydrous magnesium sulfate and filtered, and concentrated under reduced pressure . The residue was purified with ethyl acetate as eluent by silica gel chromatography to obtain 242mg of desired compound as solid in 79% of yield. mp: 193-195°C λ H NMR(CDC1 3 , 200MHz) : δ 2.39(s, 3H) , 3.15-3.29 (m, 2H) , 3.74(s, 3H) , 3.68-3.85(m, IH) , 4.05-4.27(m, IH) , 6.05-7.40(m, 7H) , 8.41(brs, IH) m/e: 360 (M + ) <Example 3> Preparation of 1- (2-methyl-4-methoxyphenyl) -4- oxo-6-methyl-2, 3,4, 5-tetrahydropyrrolo[3, 2-c]quinoline 4-0xo-6-methyl-2, 3-dihydropuro [3, 2-c] quinoline (201mg, l.Ommol) was dissolved in 10ml of diethylene glycol in a pressure tube and 2-methyl-4-methoxyaniline (322μl, 2.5mmol) was added under nitrogen. The reaction mixture was heated at 250°C for 15 hours. The reaction mixture was diluted with 20ml of salt water and the aqueous layer was extracted with methylene chloride (15ml x 3) . After washing with water (15ml x 3) , the organic layer was dried by anhydrous magnesium sulfate and filtered, and concentrated under reduced pressure. The residue was purified with ethyl acetate as eluent by silica gel chromatography to obtain 272mg of desired compound as solid in 85% of yield. mp: 210-213°C X H NMR(CDC1 3 , 200MHz) : δ 2.38(s, 3H) , 2.41(s, 3H) , 3.07-3.37(m, 2H) , 3.68-3.92(m, IH) , 3.83(s, 3H) , 4.01-4.18(m, IH) , 6.57-6.89(m, 4H) , 7.03-7.29(s, 32H) , 8 . 41 (brs , IH) m/e : 320 (M + ) <Example 4> Preparation of 1- (2-methyl-4-hydroxyphenyl) -4 -oxo-6-methyl-2, 3,4, 5-tetrahydropyrrolo[3, 2-c] quinoline 4-Oxo-6-methyl-2, 3-dihydrofuro[3, 2-c]quinoline (201mg, l.Ommol) was dissolved in 10ml of diethylene glycol in a pressure tube and 4-amino-m-cresol (308mg, 2.5mmol) was added under nitrogen. The reaction mixture was heated at 250°C for 15 hours. The reaction mixture was diluted in 20ml of salt water and the aqueous layer was extracted by methylene chloride (15ml x 3) . After washing with water (15ml x 3) , the organic layer was dried by anhydrous magnesium sulfate and filtered, and concentrated under reduced pressure. The residue was purified with ethyl acetate as eluent by silica gel chromatography to obtain 210mg of desired compound as solid in 81% of yield, mp: 244-246°C *H NMR(CDC1 3 , 200MHz) : 6 2.18(ε, 3H) , 2.39(s, 3H) , 3.05-3.39(m, 2H) , 3.74-3.94(m, IH) , 3.98-4.17(m, IH) , 6.63-7.27(m, 6H) , 8.55(brs, IH) , 9.49(brs, IH) m/e: 306 (M + ) <Example 5> Preparation of 1- (phenyl) -4-oxo-6-methoxy -2,3,4, 5-tetrahydropyrrolo [3 , 2-c] quinoline 4-Oxo-6-methoxy-2,3-dihydrofuro[3, 2-c]quinoline (217mg, l.Ommol) was dissolved in 7ml of phenol and aniline (228μl, 2.5mmol) was added under nitrogen. The reaction mixture was heated at 190°C for 15 hours. The reaction mixture was diluted with 20ml of salt water and the aqueous layer was extracted with methylene chloride (15ml x 3) . After washing with water (15ml x 3) , the organic layer was dried by anhydrous magnesium surface and filtered, and concentrated under reduced pressure. The residue was purified with ethyl acetate as eluent by silica gel chromatography to obtain 240mg of desired compound as solid in 83% of yield, mp: 75-77°C α H NMR(CDC1 3 , 200MHz) : 6 3.12 (t, J=9.2Hz, 2H) , 3.89(s, 3H) , 4.03(t, J=9.5Hz, 2H) , 6.50(d, J=7.8Hz, IH) , 6.71-7.33(m, 7H) , 8.91(brs, IH) m/e: 292 (M + ) <Example 6 > Preparation of 1- (2-methylphenyl) -4-oxo-6- methoxy-2 ,3,4, 5-tetrahydropyrrolo [3, 2-c] quinoline 4-Oxo-6-methoxy-2, 3-dihydrofuro [3, 2-c]quinoline (217mg, l.Ommol) was dissolved in 10ml of diethylene glycol in a pressure tube and 2-methylaniline (267μl, 2.5mmol) was added under nitrogen. The reaction mixture was heated at 250°C for 15 hours. The reaction mixture was diluted with 20ml of salt water and the aqueous layer was extracted with methylene chloride (15ml x 3) . After washing with water (15ml x 3) , the organic layer was dried by anhydrous magnesium sulfate and filtered, amd concentrated under reduced pressure. The residue was purified with ethyl acetate aε eluent by silica gel chromatography to obtain 235mg of desired compound as solid in 77% of yield, mp: 166-168°C l H NMR(CDC1 3 , 200MHz) : δ 2.34(s, 3H) , 3.11-3.41 (m, 2H) , 3.72-3.91(m, IH) , 3.97(s, 3H) , 4.06-4.28(m, IH) , 6.28(d, J=7.9Hz, IH) , 6.73(d, J=8.2Hz, IH) , 6.82(d, J=7.9Hz, IH) , 7.05-7.42(m, 4H) , 8.91(brs, IH) m/e: 306(M + ) J=8.2Hz, IH) , 6.82(d, J=7.9Hz, IH) , 7.05-7.42(m, 4H) , 8.91 (brs, IH) m/e: 306 (M + ) <Example 7> Preparation of 1- (2-methoxyphenyl) -4-oxo-6 -methoxy-2, 3,4, 5-tetrahydropyrrolo [3, 2-c] quinoline 4-Oxo-6-methoxy-2, 3-dihydrofuro[3,2-c]quinoline (2l7mg, l.Ommol) was dissolved in 10ml of diethylene glycol in a pressure tube and of 2-methylaniline (282μl, 2.5mmol) was added under nitrogen. The reaction mixture was heated at 250°C for 15 hours. The reaction mixture was diluted with 20ml of salt water and the aqueous layer was extracted with methylene chloride (15ml x 3) . After layer with water (15ml x 3) , the organic layer was dried with anhydrous magnesium sulfate and filtrated to be concentrated under reduced pressure. The residue was purified with ethyl acetate as a development solution according to silica gel chromatography to obtain 260mg of desired compound as solid in 81% of yield, mp: 185-188°C *H NMR(CDC1 3 , 200MHz) : 6 3.18 (t, J=9.2Hz, 2H) , 3.70-4.21(m, 2H) , 3.73(s, 3H) , 6.44(d, J=8.2Hz, IH) , 6 . 67 - 7 . 34 (m, 6H) , 8 . 87 (brs , IH) m/e : 322 (M + ) <Example 8> Preparation of l- (2-methyl-4-methoxyphenyl) -4-oxo-6-methoxy-2, 3,4, 5-tetrahydropyrrolo [3, 2-c] quin oline 4-Oxo-6-methoxy-2, 3-dihydrofuro[3, 2-c] quinoline (217mg, l.Ommol) was dissolved in 10ml of ethylene glycol and 4-methoxy-2-methylaniline (322μl, 2.5mmol) was added under nitrogen. The reaction mixture was heated at 210°C for 15 hours. The reaction mixture was diluted with 20ml of salt water and the aqueous layer was extracted with methylene chloride (15ml x 3) . After washing with water (15ml x 3), the organic layer was dried by anhydrous magnesium sulfate and filtered, and concentrated under reduced pressure. The residue was purified with ethyl acetate as eluent by silica gel chromatography to obtain 270mg of desired compound as solid in 81% of yield, mp: 188-191°C > H NMR(CDC1 3 , 200MHz) : δ 2.23 (s, 3H) , 3.05-3.35(m, 2H) , 3.80(s, 3H) , 3.88(s, 3H) , 3.80-4.11(m, 2H) , 6.27(dd, J=8.1Hz, J2=l.lHz, IH) , 6 . 65 - 6 . 85 (m, 4H) , 7 . 04 (d , J=8 . 6Hz , IH) , 8 . 83 (brs , IH) m/e : 336 (M + ) <Example 9> Preparation of 1- (2-methyl-4-fluorphenyl) -4-oxo-6-methoxy-2,3,4, 5-tetrahydropyrrolo [3, 2-c] quin oline 4-Oxo-6-methoxy-2, 3-dihydrofuro [3,2-c]quinoline (217mg, l.Ommol) was dissolved in 10ml of diethylene glycol in a pressure tube and (278μl, 2.5mmol) of 4-fluor-2-methylaniline (278μl, 2.5mmol) was added under nitrogen. The reaction mixture was heated at 250°C for 15 hours. The reaction mixture was diluted with 20ml of salt water and the aqueous layer was extracted with methylene chloride (15ml x 3) . After washing with water (15ml x 3), the organic layer was dried by anhydrous magnesium sulfate and filtered, and concentrated under reduced pressure. The residue was purified with ethyl acetate as eluent according to silica gel chromatography to obtain 256mg of desired compound as solid in 79% of yield, mp: 195-198°C X H NMR(CDC1 3/ 200MHz) : δ 2.28 (s, 3H) , 3.01-3.35(m, 2H) , 3.51-3.82(m, IH) , 3.89(s, 3H) , 3.88-4.15(m, IH) , 6.21(d, J=8.1Hz, IH) , 6.65-7.14(m, 5H) , 8.89(brs, IH) m/e: 324 (M + ) <Example 10> Preparation of 1- (3-methylphenyl) -4-oxo-6- methoxy-2, 3,4, 5-tetrahydropyrrolo [3, 2-c] quinoline 4-Oxo-6-methoxy-2, 3-dihydrofuro[3, 2-c]quinoline (217mg, l.Ommol) was dissolved in 7ml of phenol in a pressure tube and 3-methylaniline (268μl, 2.5mmol) was added under nitrogen. The reaction mixture was heated at 190°C for 15 hours. The reaction mixture was diluted with 20ml of salt water and the aqueous layer was extracted with methylene chloride (15ml x 3) . After washing with water (15ml x 3) , the organic layer was dried by anhydrous magnesium sulfate and filtered, and concentrated under reduced pressure. The residue was purified with ethyl acetate as eluent by silica gel chromatography to obtain 23Omg of desired compound as solid in 76% of yield, mp: 155-157°C *H NMR(CDC1 3 , 200MHz ) : δ 2.32 (s, 3H) , 3.16(t, J=9.2Hz, 2H) , 3.92(s, 3H) , 4.06(t, J=9.5Hz, 2H) , 6.56-7.18(m, 6H) , 7.24(t, J=6.4Hz, IH) , 8.91(brs, IH) m/e : 306 ( M + ) <Example 11> Preparation of 1- (2-methylphenyl) -4-oxo-e- trifluormethoxy-2, 3,4, 5-tetrahydropyrrolo[3,2-c]quino line 4-0xo-6-trifluormethoxy-2,3-dihydrofuro[3,2-c]quinoline (272mg, l.Ommol) was dissolved in 10ml of diethylene glycol and 2-methylaniline (267μl, l.Ommol) was added under nitrogen. The reaction mixture was heated at 250°C for 15 hours. The reaction mixture was diluted with 20ml of salt water and the aqueous layer was extracted with methylene chloride (15ml x 3) . After washing with water (15ml x 3) , the organic layer was dried by anhydrous magnesium sulfate and filtered, and concentrated under reduced pressure. The residue was purified with ethyl acetate as eluent by silica gel chromatography to obtain 298mg of desired compound as solid in 83% of yield, mp: 153-156°C X H NMR(CDC1 3 , 200MHz) : δ 2.31(s, 3H) , 3.10-3.37(m, 2H) , 3.79(q, J=10.2Hz, IH) , 4.07-4.21(m, IH) , 6.58(d, J=8.1Hz, IH) , 6.73(t, J=8.3Hz, IH) , 7.09-7.36(m, 5H) , 8.71(brs, IH) m/e: 361(M + ) <Example 12> Preparation of 1- (2-methoxyphenyl) -4-oxo-6- trifluormethoxy-2,3,4,5-tetrahydropyrrolo[3,2-c]quino line 4-Oxo-6-trifluormethoxy-2,3-dihydrofuro[3,2-c] quinoline (272mg, l.Ommol) was dissolved in 10ml of ethylene glycol in a pressure tube and 2-methoxyaniline (282μl, l.Ommol) was added under nitrogen. The reaction mixture was heated at 210°C for 15 hours. The reaction mixture was diluted with 20ml of salt water and the aqueous layer was extracted with methylene chloride (15ml x 3) . After washing with water (15ml x 3) , the organic layer was dried by anhydrous magnesium sulfate and filtered, and concentrated under reduced pressure. The residue was purified with ethyl acetate as eluent by silica gel chromatography to obtain 286mg of desired compound as solid in 76% of yield, mp: 171-173°C l H NMR(CDC1 3 , 200MHz) : δ 3.18-3.31(m, 2H) , 3.76(s, 3H) , 3.75-3.95(m, IH) , 4.05-4.27(m, IH) , 6.75-7.48(m, 7H) , 8.83(brs, IH) m/e: 377 (M + ) <Example 13> 1) Preparation of 1- (4-methoxy-2-methylphenyl) -4-chloro-6-methyl-2, 3-dihydropyrrolo [3, 2-c]quinoline 1- (4-methoxy-2-methylphenyl) -4-oxo-6-methyl-2, 3,4, 5-t etrahydropyrrolo [3, 2-c] quinoline (l.Og, 3.1mmol) was dissolved in 10ml of phosphoryl chloride (P0C1 3 ) and heated for 2 hours . The reaction mixture was stirred at room temperature for 30 minutes after cooling and addition of ice water. The reaction mixture was extracted with methylene chloride (20ml x 3) . After washing with water (15ml x 3) , the organic layer was dried by anhydrous magnesium sulfate and filtered, and concentrated under reduced pressure. The residue was purified by silica gel chromatography to obtain 786mg of desired compound as an oil in 75% of yield. *H NMR(CDC1 3 , 200MHz) : δ 2.24(s, 3H) , 2.65(s, 3H) , 3.05-3.35(m, 2H) , 3.85(s, 3H) , 3.80-4.11(m, 2H) , 6.27(dd, J 1= 8.1Hz, J 2 =l.lHz, IH) , 6.65-6.89(m, 4H) , 7.05(d, J=8.4Hz, IH) m/e: 338 (M + ) 2) Preparation of 1- (4-methoxy-2-methylamino) -6 -methyl-2,3-dihydropyrrolo[3,2-c]quinoline (IV) 1- (4-methoxy-2-methyl phenyl) -4-chloro-6-methyl -2, 3-dihydropyrrolo [3,2-c]quinoline (496mg, 1.2mmol) was dissolved in 10ml of ethyl alcohol and 5ml of 40% aqueous methylamine was added. The reaction mixture was heated at 170°C for 20 hours in a pressure tube and solvent was distilled under reduced pressure. The reaction mixture was diluted with 20ml of methylene chloride. After washing with water (15ml x 3) , the organic layer was dried by anhydrous magnesium sulfate and filtered, and concentrated under reduced pressure. The residue was purified by silica gel chromatography to obtain 324mg of desired compound in 81% of yield. X H NMR(CDC1 3 , 200MHz) : δ 2.27(s, 3H) , 2.64(s, 3H) , 2.91-3.20(m, 2H) , 3.11(d, 3H) , 3.65-3.82(m, IH) , 3.81(s, 3H) , 4.03-4.21(m, 2H) , 6.68-6.81(m, 3H) , 6.83-6.90(m, 2H) , 7.20-7.31 (m, IH) m/e: 333 (M + ) <Example 14 > 1) Preparation of 1- (2-methylphenyl) -4-oxo-6- methyl-4, 5-dihydropyrrolo [3, 2-c] quinoline (IX) 1- (2-methylphenyl) -4-oxo-6-methyl-2 ,3,4,5- tetrahydropyrrolo[3, 2-c] quinoline (290mg, l.Ommol) was dissolved in 20ml of diphenyl ether and 4Omg of 5% palladium/carbon was added. The reaction mixture was heated for 4 hours . The reaction mixture was cooled to the room temperature and directly purified by silica gel chromatography to obtain 245mg of desired compound as solid in 85% of yield. mp:224-227°C 1 H NMR(CDC1 3 , 200MHz) : δ l.93(s, 3H) , 2.81(s, 3H) , 6.93-7.02(m, 2H) , 7.15-7.63 (m, 7H) , 8.56(bra, IH) m/e: 288 (M + ) 2) Preparation of 1- (2-methylphenyl) -4-chloro -6-methylpyrrolo [3, 2-c] quinoline (X) 1- (2-methylphenyl ) -4-oxo-6-methyl-4,5- dihydropyrrolo[3, 2-c] quinoline (1.16g, 4.0mmol) was dissolved in 10ml of phosphoryl chloride (P0C1 3 ) and heated for 2 hours. The reaction mixture was stirred at room temperature for 30 minutes after cooling and 5H) m/e: 306 (M + ) 3) preparation of 1- (2-methylphenyl) -4- [ (2- hydroxyethyl) amino] -6-methylpyrrolo [3 , 2-c] quinoline (III) 1- (2-methylphenyl) -4-chloro-6-methylpyrrolo [3, 2-c] quinoline (306mg, l.Ommol) was dissolved in 10ml of ethanolamine in a pressure tube and heated at 150°C for 3 hours. After removal of the reaction solvent under reduced pressure and diluted in 20ml of methylene chloride, the residue was dried by anhydrous magnesium sulfate and filtered, and concentrated under reduced pressure. The residue was purified by silica gel chromatography to obtain 236mg of desired compound as solid in 72% of yield. mp: 187-189°C : H NMR(CDC1 3 , 200MHz) : δ 1.93(s, 3H) , 2.69(s, 3H) , 3.91-3.99(m, 4H) , 5.61(bra, IH) , 6.67-7.01(m, 5H) , 7.25-7.52(m, 5H) m/e: 331(M * ) Effect of the invention As apparent from the above examples, the process for preparing 1-aryl-4-oxopyrrolo[3, 2-c] quinoline derivatives I according to the present invention adopts reagents of low cost under mild reaction conditions and the compound I may be prepared from the compound II in a single step. Especially, the preparation process according to the present invention can introduce various substituents such as R 1 , R 2 , R 2 and R 4 which have not been introduced in the prior art. Therefore, according to the present process, the compound IV which is a reversible inhibitor of the gastric acid secretion and has various substituents may be prepared safely and economically in high yield from the 1-aryl-4-oxopyrrolo[3, 2-c] quinoline derivatives.

Claims: What is claimed is : 1. A process for preparing 1-aryl-4-oxopyrrolo [3, 2-c]quinoline derivatives aε represented by formula I, by reaction of 4-oxofuro[3 , 2-c]quinoline compounds as represented by formula II with anilines aε represented by formula III: wherein, R 1 may be same or different from R 2 which are respectively hydrogen, lower alkyl group of C]-C 4 , lower alkoxy group of C.-C,, lower alkylthio group of C\-C 4 , lower haloalkoxy group of Ci-C,, trifluoromethyl group, hydroxyalkoxy group of C.-C,, halogen, or hydroxy group; and R 2 may same or different from R" which are halogen, or hydroxy group; and R 3 may same or different from R 4 which are respectively hydrogen, lower alkyl group of C 1 -C 4 , lower alkoxy group of C 1 -C 4 , lower alkylthio group of C x -C 4 lower haloalkyl group of C 1 -C 4 , trifluoromethyl group, hydroxy group, amino group, or halogen. 2. The process as claimed in claim 1, wherein R 1 , R 2 , R 3 and R 4 are same or different from each other and to be respectively hydrogen, methyl or methoxy. 3. The process as claimed in claim 1, wherein R 1 , R 2 , R 3 and R 4 are same or different from each other and to be respectively methyl, hydroxy or fluoro. 4. The process as claimed in claim 1, wherein R 1 , and R 2 are respectively hydrogen or hydroxyalkoxy group, and R 3 and R" are same or different from each other and to be respectively hydrogen, methyl or methoxy. 5. The process as claimed in claim 1, wherein R 1 , and R 2 are respectively hydrogen or hydroxyalkoxy group, and R 3 and R 4 are same or different from each other and to be respectively methyl, hydroxy or fluoro. the reaction solvent is selected from dimethyl formamide, dimethylsulfoxide, diphenyl ether, xylene, butyl alcohol, phenol, ethylene glycol, diethylene glycol, triethylene glycol, polyetylene glycol, and ethylene glycol monomethyl ether. 7. The process as claimed in claim 1, wherein the reaction temperature is 70-300°C. 8. The process as claimed in claim 1, wherein the amount of the aniline compounds is used 1-3 equivalents for 4-oxofuro [3 , 2-c] quinoline compounds. 9. A process for preparing the compound as represented by formula IV by reacting 4-oxofuro [3, 2-c] quinoline compounds as represented by formula II with aniline compounds as represented by formula III in a reaction solvent through a single step to obtain a compound aε represented by formula I, adding P0C1 3 to the compound I to obtain compound aε represented by formula VIII, and adding alkylamine to the compound VIII.

Inventors: CHO SUNG YUN, CHOI JOONG KWON, KANG SEUNG KYU, KIM SUNG SOO, YUM EUL KYUN, CHO, SUNG, YUN, CHOI, JOONG, KWON, KANG, SEUNG, KYU, KIM, SUNG, SOO, YUM, EUL, KYUN
Applicants: CHO SUNG YUN, CHOI JOONG KWON, KANG SEUNG KYU, KIM SUNG SOO, KOREA RES INST CHEM TECH, YUM EUL KYUN, CHO, SUNG, YUN, CHOI, JOONG, KWON, KANG, SEUNG, KYU, KIM, SUNG, SOO, KOREA RESEARCH INSTITUTE OF CHEMICAL TECHNOLOGY, YUM, EUL, KYUN
Application year: 1997
Main classification: C07D471
IPC codes: A61K31, A61P1, C07D471, C07D491