Selective acylation of A-ring precursors of vitamin D using enzymes in organic solvents

Article abstract of DOI:10.1021/jo00124a014

Whereas Chromobacterium viscosum lipase (CVL) catalyzes selectively the acylation of the C-5 hydroxyl of the three stereoisomeric vitamin D A-ring precursors 2a, 3a and 3b, only the C-3 hydroxyl of the fourth stereoisomer 2b is acylated under the same conditions in organic solvent. In a convenient application, the racemic vitamin D A-ring precursor 4, possessing only the C-5 hydroxyl, was resolved using suitable conditions identified from the studies of 2 and 3.