| 摘要 |
<p>Cephalosporins of formula (I) and their non-toxic salts are new. In (I), R is H, alkyl; X is H, alkyl, halogen, OH; z is H, OCH3. (I) are antibacterials active against both Gram-positive and Gram-negative organisms. Specific (I) include that in which R is methyl and X and Z are both H. In an example, this is prepd. by reacting 2-(5-methyl-1,3,4-thiadiazol-2-ylthio)acetic acid with pivaloyl chloride in the presence of triethylamine, reacting the product with 7-aminocephalosporanic acid in the presence of triethylamine, and reacting the resulting 7-acylaminocephalosporanic acid with tetrazolo/4,5-b/pyridazine-6-thiol.</p> |
