Patent ID: 7935827

Claim:
A process for the preparation of a compound of formula I, wherein: A is a bicyclic heteroaromatic residue of formula wherein “heteroaromatic” stands for a 5- or 6-membered heteroaromatic ring having up to 2 heteroatoms selected from oxygen, nitrogen or sulphur, which is optionally substituted with one or two substituents selected from alkyl, optionally protected hydroxyalkyl, halo-alkyl, halogen or CN, and R is a straight-chain or branched, optionally saturated alkyl chain, which optionally contains 1-3 oxygen atoms; phenyl; cyclohexyl; or benzyl residue, comprising subjecting a β-ketoester of formula IV to a chemical or microbiological reaction converting the oxo group of formula II to the hydroxyl group of Formula I.