Patent ID: 6214997
Filing Date: 2001-04-10
Classification: C07D

Abstract:
A process for the preparation of crystalline (Z)-2-(2-tert. -butoxycarbonylprop-2-oxyimino)-2-(2-triphenylmethylaminothiazol-4-yl) acetic acid of Formula (IV) ##STR5##in association with 0.3 to 0.6 moles of N,N-dimethylformamide per mole of acid which comprises treating ethyl (Z)-2-(2-aminothiazol-4-yl)-2-hydroxyiminoacetate of Formula (I) ##STR6##with tert.-butyl 2-bromoisobutyrate to give ethyl (Z)-2-(2-aminothiazol-4-yl)-2-(2-tert. -butoxycarbonyl-prop-2-oxyimino)acetate of Formula (II) ##STR7##converting said acetate of Formula (II) into acid of Formula (III) ##STR8##tritylating said acid with triphenylchloromethane to give a solution of (Z)-2-(2-tert-butoxycarbonylprop-2-oxyimino)-2-(2-triphenylmethylaminothia zol-4-yl) acetic acid in N, N-dimethylformamide; and precipitating the desired compound of Formula (IV) associated with N, N-dimethylformamide.