NOVEL 3-SUBSTITUTED CEPHEM COMPOUNDS AND PROCESSES FOR PREPARATION THEREOF

摘要

The present invention relates to novel cephalosporins of formula (I), wherein R1 represents A C1 SIMILAR C4 alkyl group or ( alpha ), wherein R2 and R3, independently, represent hydrogen or a C1 SIMILAR C3 alkyl group and R4 represents hydrogen or a C1 SIMILAR C4 alkyl group; R1a represents hydrogen or an amino-protecting group; Q represents CH or N; and formula ( beta ) represents a saturated or unsaturated heterocyclic group which contains 1 to 4 nitrogen atoms of which one is substituted with an amino group to form quaternary ammonium, and oxygen or sulfur, or a fused heterocyclic group thereof formed together with a substituted or unsubstituted benzene or an optional heterocyclic group, or a pharmaceutically acceptable salt thereof, to processes for preparing the same and to a pharmaceutical composition containing the same as an active ingredient. The compounds (I) according to the invention exhibit potent antibacterial activity and broad antibacterial spectrum against the Gram-positive strains including Staphylococcus as well as Gram-negative strains including Pseudomonas, and, therefore, are expected to be very useful in treatment of various diseases caused by bacterial infection in human beings and animals.