| abstract |
The present invention is concerned with compounds of formula (I)n wherein nZ is C₅₋₁₂ straight or branched alkyl, C₃₋₁₂ alkenyl or alkynyl, C₆ or C₁₀ aryl, C₆ or C₁₀ aryl-C₁₋₁₂ alkyl (wherein in either case the aryl group is optionally substituted by one or more groups independently selected from phenyl, C₁₋₄ alkyl, C₁₋₄ alkoxy, nitro, and halo) or C₄₋₈ cycloalkyl-C₁₋₁₂ alkyl; nZ¹ is a group of formula -CH₂-X-X¹-X², wherein X is selected from -(CH₂)₂-and cis and trans -CH=CH-, X¹ is a covalent bond or a straight or branched alkylene chain having from 1 to 6 carbon atoms optionally having one of its methylene groups replaced by oxa (-O-) or this (-S-) provided that at least one carbon atom separates the oxa or thia group from a carboxyl or -CH=CH-group, and X² is a carboxyl group, a C₁₋₄ alkyl ester, or an amide group; nZ² is a group selected from -NH-CH₂-R and -N=CH=R, wherein R is a group selected from -CO-Y and -CH(Y¹)-Y, Y being a group selected from C₃₋₈ alkyl, C₃₋₈ alkenyl, phenyl-C₁₋₄ alkyl and phenyl (wherein the phenyl group in both cases is optimally substituted by one or more groups independently selected from C₁₋₄ alkyl, C₁₋₄ alkoxy, nitro, halo and trihalomethyl), C₄₋₈ cycloalkyl, and 5- or 6-membered heterocyclic radicals containing at least one heteroatom selected from oxygen, sulphur and nitrogen; and Y¹ being a group selected from hydrogen, hydroxy, C₁₋₄ alkoxy and C₂₋₅ acyloxy; and salts and solvates thereof. |