Patent ID: 6384233
Filing Date: 2002-05-07
Classification: A61P,C07C,C07D

Abstract:
A process for preparing a compound of the formula I whereinR1, R2, R3 and R4 are the same or different and are individually selected from the group consisting of hydrogen, lower alkyl, lower alkoxy, amino, acetamido, phenyl, halo, hydroxy, lower alkylsulfonyl, lower alkylthio, nitro, trifluoromethyl, omega-trifluoromethyl lower alkoxy, or where R1, R2 or R3, R4 taken together with the phenyl group to which they are attached, form a naphthyl or substituted naphthyl group; comprising reacting a compound of formula II wherein R3 and R4 are as described above, with succinic anhydride and an alkoxide base to form a compound of formula III wherein R3 and R4 are described above, reacting the compound of formula III with a compound of formula IV wherein R1 and R2 are as described above, to form a compound of formula V which is isolated reacting the compound of formula V with an alcohol to form the corresponding ester of formula VI wherein R is lower alkyl, which is isolated and reacting the isolated ester with N-methylhydroxylamine hydrochloride to form the compound of formula I.