| 摘要 |
<p>7-Acylamido-, and 7-amino-3-alkoxy-3-cephem-4-carboxylic acids are prepared by reacting a 7-acylamido-, or 7-amino-3-methylenecepham-4-carboxylic acid ester with ozone, and decomposing the ozonide which is formed to provide an intermediate 7-acylamido-, or 7-amino-3-hydroxy-3-cephem-4-carboxylic acid ester. Reaction of the 3-hydroxy-3-cephem with a diazoalkane followed by removal of the ester group provides a compound of the invention. The 3-alkoxy-3-cephem acids are valuable antibiotic compounds.</p> |
