Polyketides and their synthesis

摘要

A type I polyketide synthase which comprises a loading module and a plurality of extension modules, wherein said loading module is adapted to load an optionally substituted malonyl and then to effect decarboxylation of the loaded residue to provide a corresponding optionally substituted acetyl residue for transfer to the first of said extension modules, and wherein at least said first extension module is not naturally associated with a loading module that effects decarboxylation; with the proviso that the target polyketide is not a 14-membered macrolide having a 13- methyl group due to incorporation of an (unsubstituted) acetate starter unit.