A novel and efficient procedure has been developed for the preparation of the C-7 side chain of ceftobiprole,(Z)-2-(5-amino-1, 2, 4-thiadiazole-3-yl)-2-trityloxyiminoacetic acid (2) from malononitrile (9) in a total yield of 19%. The key intermediate N-(3-(2-acetamido-2- oxoethyl)-1, 2, 4-thiadiazol-5-yl) benzamide (15b) was synthesized for the first time in 76% yield by treatment of N-(3-aminoisoxazol-5-yl) acetamide (13) with benzoyl isothiocyanate. ...