摘要:
Cephem derivatives represented by the formula: ##STR1## wherein R.sub.1 represents a hydrogen atom or a hydroxyl group, R.sub.2 represents a lower alkyl group or a chloro-substituted lower alkyl group, and R.sub.3 represents a lower alkanoyloxy group or a nitrogen-containing heterocyclic thio group,and the pharmaceutically acceptable salts thereof. The cephem derivatives exhibit excellent antibacterial activity and are effective against Gram-positive and Gram-negative bacteria.
摘要:
New chromone derivatives having the formula: ##STR1## wherein A represents a hydrogen atom, a halogen atom or a hydroxyl group, and R.sub.1 represents a lower alkyl or a chloro-substituted lower alkyl group. The derivatives are useful intermediates for synthesis of cephem derivatives as antibacterial drugs.