| 摘要 |
<p>NEW MATERIAL:Cephalosporin analogs of formula I (X is acyl; R<1> is H, carboxyl- protecting group) and their salts. EXAMPLE:( + or - )cis-7beta-[ ( R )-2-phenyl-2-aminoacetamide ]-4beta-methyl-2-carboxy- 1-azabicyclo[4,2,0]oct-2-en-8-one trifluoroacetate. USE:Antibiotic and its synthetic intermediates. The analogs with R<1> of H has outstanding antibacterial activity against gram-positive and negative bacteria. PREPARATION:For example, the reaction of a compound of formula II' and a carboxylic acid corresponding to acyl group X or its reactive derivative gives the compound of formula I. When necessary, a base is used in the reaction. When R<1> is a carboxyl-protecting group, it is removed and the product is converted into the antibacterial compound with R<1> of H.</p> |
