Thiourea → 7-[2-(2-Amino-4-thiazolyl)-2-methoxyiminoacetamido]-3-cephem-4-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

Thiourea (8.4 mg.) was added to a solution of 7-(2-methoxyimino-3-oxo-4-bromobutyramido)-3-cephem-4-carboxylic acid (syn isomer, 42 mg.) in ethanol (6 ml.) and stirred at room temperature for an hour and at 50° C. for 30 minutes. After removing ethanol from the reaction mixture in vacuo, water (5 ml.) was added to the residue and adjusted to pH 4.0 with 6 N-hydrochloric acid. The precipitates were collected by filtration and dried to give 7-[2-(2-aminothiazol-4-yl)-2-methoxyiminoacetamido]-3-cephem-4-carboxylic acid (syn isomer, 8 mg.). The filtrate was subjected to column chromatography on nonionic, adsorption resin "Diaion HP-20" (trademark: manufactured by Mitsubishi Chemical Industries Ltd., 5 ml.), washed with chilled water (5 ml.) and eluted with 20% aqueous isopropyl alcohol. The eluate was adjusted to pH 6.5 with 1 N aqueous sodium hydroxide under ice-cooling, and concentrated in vacuo. The residue was lyophilized to give sodium 7-[2-(2-aminothiazol-4-yl)-2-methoxyiminoacetamido]-3-cephem-4-carboxylate (syn isomer, 15 mg.).

Provenance & Evidence