PENEM DERIVATIVES AND PHARMACEUTICAL COMPOSITIONS

摘要

A compound of formula I in which R represents a hydrogen atom or a carboxylic acid esterifying group; R<1> represents (i) one of the following groups in which Ra and Rb, which may be the same or different, each represents an alkyl group having from 1 to 4 carbon atoms, or (ii) a -CONH(CH2)m Q group, in which m represents an integer of from 1 to 3, and Q represents one of the following groups in which Rc represents a methyl or ethyl group, or (iii) a -CO2Rd group, in which Rd represents a methyl or ethyl group which is unsubstituted or is substituted by one or more substituents, which may be the same or different, selected from (a) halogen atoms and vinyl groups, (b) phenyl groups which are unsubstituted or are substituted by one or more groups selected from alkoxy groups having from 1 to 4 carbon atoms, nitro groups and halogen atoms, (c) silyl groups SiReRfRg, the groups Re, Rf and Rg being the same or different, each representing a phenyl group or an alkyl group having from 1 to 4 carbon atoms, and (d) groups Q as defined above; or (iv) a -CO2SiReRfRg group, in which Re, Rf and Rg are defined as in (c) above, or a -CO2-phenyl group, in which the phenyl moiety is unsubstituted or substituted as defined in (b) above; R<2> represents (i) a hydrogen atom, (ii) a group as defined above for R<1> (R<1> and R<2> being the same or different), or (III) a chlorine, bromine or iodine atom, an alkyl group having from 1 to 4 carbon atoms, an -NH2-, -NHRa or -NRaRb group, an -OH or -ORa group, or an -OCOCH3 group. Ra and Rb being defined as above, and R<3> represents a hydrogen atom or a hydroxy protecting group; and in which R<1> and R<2>, independently of each other, may be present at any position on the phenyl ring; and salts thereof, and isomers thereof have antibacterial activity.