| 摘要 |
<p>ENOL DERIVATIVES AND PROCESS FOR THEIR MANUFACTURE The invention relates to O-substituted 7.beta.-arnino-3-cephem-3-o1-4-carboxylic acid compounds of the formula (IA) wherein R1 represents hydrogen or an amino protective group R? and R? represents hydrogen or an acyl group Ac, or R? and R? together represent a bivalent amino protective group, R2 represents hydroxyl or a radical R? which together with the carbonyl grouping -C(=O)- forms a protected carboxyl group and R3 represents an optionally substituted hydrocarbon radical or an acyl group, and to 1-oxides of 3-cephem compounds of the formula I, and also to the corresponding 2-cephem compounds of the formula (IB) wherein R?, R?, R2 and R3 have the abovementioned meanings, or salts of such compounds with salt-forming groups. 3-Cephem compound of the formula IA, particularly those, in which R? represents an acyl group, R? is hydrogen and R2 is hydroxy, exhibit pronounced antimicrobial effects, the others, and particularly the 1-oxides of these 3-cephem compounds and the corresponding 2-cephem vompounds are useful as intermediates.</p> |
