Chiral auxiliaries as docking/protecting groups in biohydroxylation:: (S)-specific hydroxylation of enantiopure tert-butyl-substituted spirooxazolidines derived from cyclopentanone

An enantiopure tert-butyl-substituted derivative of cyclopentanone, which is a vital member of the chiral docking/ protecting group series, is employed, for the first time, to stereoselectively (90 % de) introduce an (S)-configured hydroxyl group onto an unactivated carbon atom present in the cyclopentane ring using the fungus Beauveria bassiana ATCC 7159. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005).