Patent ID: 6353119
Filing Date: 2002-03-05
Classification: C07D

Abstract:
A process for preparing a quinoline compound of the formula whereinR is hydrogen or methyl; R1 is bromo, chloro or nitro; and R2, R3 and R4 each are independently hydrogen, halogen, nitro or trifluoromethyl, provided R2, R3, and R4 are not all hydrogen; or a nontoxic pharmaceutically acceptable salt thereof; comprising the steps of: (a) treating a compound of formula III â€ƒwith an acid to produce a cyclic compound of formula IV â€ƒwherein R1 is bromo, chloro or nitro; (b) reacting the compound of formula IV with a substituted aniline of formula V â€ƒwherein R2, R3, and R4 are as defined above; to produce a compound of formula VI â€ƒwherein R1, R2, R3, and R4 are as defined above and R is hydrogen; (c) optionally methylating the compound of formula VI wherein R is hydrogen to produce a compound of formula VI wherein R is methyl; and (d) cyclizing a compound of formula VI wherein R is hydrogen or methyl and R1, R2, R3, and R4 are as defined above by photochemical irradiation to produce the quinoline compound of formula I.