| abstract |
"OPTICALLY ACTIVE HETEROAROMIC BETA HYDROXY ESTERS, PROCESSES FOR PREPARATION FROM BETA KETOSTERS AND PROCESSES FOR PREPARING THESE BETA KETOSTERS". The present invention relates to optically active heteroaromatic α-hydroxy esters of formula (I) useful in the synthesis of epothilone derivatives, the beta-ketoesters of formula (IV) employed to produce these intermediates by asymmetric hydrogenation with a chiral metal catalyst or microbiological or enzymatic reduction, as well as processes for its production (I), wherein: A is a bicyclic heteroaromatic residue of formula (A), heteroaromatic wherein 'heteroaromatic' represents a heteroaromatic ring of 5 or 6 members having up to 2 heteroatoms selected from oxygen, nitrogen or sulfur, which is optionally substituted with one or two substituents selected from alkyl, optionally protected hydroxyalkyl, haloalkyl, halogen or CN, and R is a straight chain or alkyl chain optionally saturated branched optionally containing 1 to 3 oxygen atoms; phenyl; cyclohexyl; or benzyl (IV) residue. |