Adger B, Bes M T, Grogan G, McCague R, Pedragosa-Moreau S, Roberts S M, Villa R, Wan P W, Willetts A J
Chiroscience Ltd., Cambridge, U.K.
Bioorg Med Chem. 1997 Feb;5(2):253-61. doi: 10.1016/s0968-0896(96)00234-9.
2-(2-Acetoxyethyl)cyclohexanone (4) was converted into the lactone (-)-(5) regio- and enantioselectively using 2-oxo-delta 3-4,5,5-trimethylcyclopentenyl acetyl-CoA monooxygenase, an NADPH-dependent Baeyer-Villiger monooxygenase from camphor grown Pseudomonas putida NCIMB 10007. The lactone (-)-(5) was converted into (R)-(+)-lipoic acid in six steps. In contrast cyclopentanone monooxygenase, an NADPH-dependent Baeyer-Villiger monooxygenase from cyclopentanol-grown Pseudomonas sp. NCIMB 9872 selectively oxidized the (S)-enantiomer of the ketone (4) giving better access to optically enriched, naturally occurring lipoic acid.
