| 摘要 |
Novel 3-vinyl-cephalosporins of the formula <IMAGE> (I) in which n is 0 or 1, R1 is hydrogen, a radical of the formula <IMAGE> (II) [in which R4 is hydrogen or a protective radical and R5 is hydrogen, alkyl, vinyl or cyanomethyl or is a protective radical], or a protective radical, and R2 is hydrogen, a protective radical or an enzymatically removable radical, or R1 is hydrogen or an acyl radical which may carry various substituents and R2 is hydrogen or a protective radical, and R3 is a radical of the general formula R'3-SO2-O- or R''3-CO-O-, in which R'3 is alkyl, trifluoromethyl, trichloromethyl or phenyl which is substituted by a halogen atom or by an alkyl or nitro radical, and R''3 is defined like R'3 or represents methyl which is substituted by acyl or alkoxycarbonyl, or represents ethyl or propyl substituted in the 2-position by acyl or alkoxycarbonyl. These compounds are useful as intermediates for the preparation of antibiotic 3-thiovinyl-cephalosporins. |
