BETA-LACTAM ANTIBIOTICS,THEIR PREPARATION,PHARMACEUTICAL COMPOSITIONS CONTAINING THEM AND THEIR USE AS GROWTH-PROMOTERS IN LIVESTOCK REARING OR AS ANTIOXIDANTS

摘要

Novel beta -lactam antibiotics of the formula IMAGE in which R1, R2 and R3, which may be identical or different, denote a substituted or unsubstituted alkyl radical or a monocyclic or bicyclic, optionally substituted, carbocyclic or heterocyclic ring, or R1 represents an optionally substituted alkyl radical or a monocyclic or bicyclic, substituted or unsubstituted, carbocyclic or heterocyclic ring, and R2 and R3, together with the N(+) atom, form an optionally substituted monocyclic or polycyclic ring which can be saturated or unsaturated and can contain oxygen, sulphur and nitrogen as other hetero atoms, or R1, R2 and R3, together with the N(+) atom, form a bridged, optionally substituted polycyclic ring which can be saturated or unsaturated and can contain oxygen, sulphur and nitrogen as other hetero atoms, and R4 represents hydrogen or optionally substituted alkyl, aryl or heterocyclyl or hydroxycarbonyl, lower alkoxycarbonyl, halogen, pseudohalogen or a group of the formula IMAGE in which n denotes 0, 1 or 2, and B represents a direct bond, oxygen or a group IMAGE and A and W, independently of one another, represent hydrogen or optionally substituted alkyl, aryl or heterocyclyl, or together form an optionally substituted carbocyclic or heterocyclic ring.