| 摘要 |
<p>PURPOSE:To obtain the titled compound useful as an antimicrobial agent readily in high yield, by reacting a specific 3-cephem-4-carboxylic acid derivative having a 7beta-side chain with a reactive derivative of a carboxylic acid to acrylate the 7beta-side chain directly. CONSTITUTION:A 7beta-(4-carboxybutyramido)-7alpha-methoxy-3-substituted methyl- 3-cephem-4-carboxylic acid derivative of formula I (R<1> and R<2> are OH or protecting groups of COOH; A is acetoxy, carbamoyloxy, etc.) is reacted with a compound of the formula R<3>-OH (R<3> is monochloroacetyl, dichloroacetyl, etc.) in an inert solvent, e.g. benzene or toluene, and the protecting group R<2> of the carboxyl group is optionally removed to give a cephalosporin derivative of formula II (Y is OH or protecting group of COOH) and a salt thereof. The reaction temperature is preferably 60-120 deg.C.</p> |
