| 摘要 |
<p>Disclosed are novel cephalosporin derivatives of the formula < IMG > I wherein R1 is hydrogen or a conventional amino-protecting group, and R2 is a straight or branched alkyl group containing from 1 to 4 carbon atoms, allyl, 2-butenyl or 3-butenyl, or is a group < IMG > wherein R3 and R4 each are independently hydrogen, methyl or ethyl, or R3 and R4, taken together with the carbon atom to which they are attached, may be a cycloalkylidene ring containing from 3 to 5 carbon atoms, and nontoxic pharmaceutically acceptable salts, physiologically hydrolyzable esters and solvates thereof and processes for their preparation. Said novel cephalosporin derivatives exhibit potent antibacterial activity.</p> |
