6,7-Dihydro-8-(imidazol-1-yl)-5-methyl-1-oxo-1H,5H-benzo(ij)quinolizine-2-carboxylic acids and derivatives

Claim 1

A compound of the formula wherein X is hydrogen or halogen selected from fluorine, chlorine or bromine; or a derivative selected from the group consisting of an ester, the acyl chloride, an alkylaminoalkyl ester salt, a salt involving a nitrogen atom of the imidazole ring, and a pharmaceutically acceptable carboxylate salt thereof.

Claim 16

A method for the preparation of a compound of the formula wherein X is hydrogen or halogen selected from fluorine, chlorine or bromine; or a derivative which is an ester, the acyl chloride, an alkylaminoalkyl ester salt, a salt involving a nitrogen atom of the imidazole ring, or a pharmaceutically acceptable carboxylate salt thereof, comprising the steps of : a) cyclizing an N-(2,2-dialkoxyethyl)-N'-(2-methylquinolin-5-yl)thiourea of the formula wherein X is as defined above and each R l is independently an alkyl group containing 1 to about 4 carbon atoms, to provide a 5-(2-mercaptoimidazol-1-yl)-2-methylquinoline of the formula wherein X is as defined above, and b) desulfurizing the 5-(2-mercaptoimidazol-l-yl)-2-methylquinoline from step a) to provide a 5-(imidazol-1-yl)-2-methylquinoline of the formula wherein X is as defined above, and c) reducing the 5-(imidazol-1-yl)-2-methylquinoline from step b) to provide a 5-(imidazol-1-yl)-1,2,3,4-tetrahydro-2-methylquinoline of the formula wherein X is as defined above, and d) condensing the 5-(imidazol-1-yl)-1,2,3,4-tetrahydro-2-methylquinoline from step c) with a diester of an alkoxymethylenemalonic acid of the formula wherein alk is an alkyl group containing 1 to about 4 carbon atoms and each R 2 is independently an alkyl group containing 1 to . about 4 carbon atoms, or the R 2 's together form an isopropyl radical, to provide an antermediate of the formula wherein X and each R 2 are as defined above, and e) cyclizing and deesterifying the imtermediate from step d) to provide said 6,7-dihydro-8- f) and, if necessary, forming the appropriate derivative.

Claim 17

A method for the preparation of a compound of the formula wherein X is hydrogen or halogen selected from fluorine, chlorine or bromine; or a derivative which is an ester, the acyl chloride, an alkylaminoalkyl ester salt, a salt involving a nitrogen atom of the imidazole ring, or a pharmaceutically acceptable carboxylate salt thereof, comprising the steps of : a) cyclizing an N-(2,2-dialkoxyethyl)-N'-(2-methylquinolin-5-yl)thiourea of the formula wherein X is as defined above and each R l is independently an alkyl group containing 1 to about 4 carbon atoms, to provide a 5-(2-mercaptoimidazol-1-yl)-2-methylquinoline of the formula wherein X is as defined above, and b) desulfurizing the 5-(2-mercaptoimidazol-l-yl)-2-methylquinoline from step a) to provide a 5-(imidazol-1-yl)-2-methylquinoline of the formula wherein X is as defined above, and c) reducing the 5-(imidazol-1-yl)-2-methylquinoline from step b) to provide a 5-(imidazol-1-yl)-1,2,3,4-tetrahydro-2-methylquinoline of the formula wherein X is as defined above, and d) condensing the 5-(imidazol-1-yl)-1,2,3,4-tetrahydro-2-methylquinoline from step c) with a diester of an alkoxymethylenemalonic acid of the formula wherein alk is an alkyl group containing 1 to about 4 carbon atoms and each R 2 is independently an alkyl group containing 1 to . about 4 carbon atoms, or the R 2 's together form an isopropyl radical, to provide an antermediate of the formula wherein X and each R 2 are as defined above, and e) cyclizing and deesterifying the imtermediate from step d) to provide said 6,7-dihydro-8- f) and, if necessary, forming the appropriate derivative.