Antibacterial (2)-alkyl-cephalosporins - with (7)-thiazolyl alkanoamido side-chain

摘要

Cephalosporins of formula (I) and their salts are new: (where R1 is alkyl; R2 is opt. protected CO2H; R3 is opt. protected NH2; A is alkylene). Specif. (I) are 2-methyl-7- 2-(2-aminothiazol-4-yl)acetamido -3-cephem-4-carboxyl- ic acid, pivaloyloxymethyl ester and its hydrochloride. (I) are useful in man and animals. A typical cpd., 2-methyl-7- 2-(2-aminothiazol-4-yl) acetamido -3-cephem-4-carboxylic acid, is prepd. by reaction of 2-(2-aminothiazol-4-yl)acetyl chloride in CH2Cl2 with sodium 2-methyl-7-amino-3-cephem-4-carboxylate in acetone, then treating the mixt. with HCl.