Patent ID: 6613914
Filing Date: 2003-09-02
Classification: A61P,C07C,C07D

Abstract:
A process for preparing a compound of 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, amino, acetamido, carboxy, alkylhydroxamic acid, 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 the compound of formula V with an alcohol to form a reaction mixture comprising the corresponding ester of formula VI without isolating the ester of formula VI, and reacting the reaction mixture of the ester of formula VI with N-methylhydroxylamine hydrochloride to form the compound of formula I.