Novel cephalosporin compounds and processes for preparation thereof

摘要

The present invention provides a cephalosporin compound represented by formulas (I-S) and (I-R) (I-S) (I-R) wherein: R1 is a C1-4 alkyl, C3-4 alkenyl, C3-4 cycloalkyl, amino optionally substituted with a C1-4 alkyl radical, phenyl, or 2-,4- or 6- substituted phenyl group with two or fewer substitutents chosen from C1-4 alkyl, C1-3 alkoxy, halogen and hydroxy radicals; R2 is hydrogen or a C1-4 alkyl group; Ra and Rb, which should be different from each other, are hydrogen or a C1-4 alkyl group; and Q is N or CH, and the pharmaceutically acceptable non-toxic salts, physiologically hydrolyzable esters, hydrates and solvates thereof, which possess potent and broad antibacterial activities. The invention also provides processes for preparing these compounds and to pharmaceutical compositions containing them as active ingredients.