名称:
Enzymes in organic synthesis. 48. Pig liver esterase and porcine pancreatic lipase catalyzed hydrolyses of 3,4-(isopropylidenedioxy)-2,5-tetrahydrofuranyl diesters
摘要:
Pig liver esterase (PLE) and porcine pancreatic lipase (PPL) catalyzed hydrolyses of 2,5-bis(methoxycarbonyl) and 2,5-bis(acetoxymethyl) meso-diester derivatives of 3,4-(isopropylidenedioxy) tetrahydrofuran proceed with enantiotopic selectivity to give monoester products of up to 72% ee. Transesterification of the 2,5-bis(hydroxymethyl) derivative with trifluorethyl laurate promoted by PPL in ether also proceeds stereoselectively but in the opposite stereochemical sense from the hydrolysis of the corresponding diacetate. The data provide further examples of heteroatom and ester moiety induced reversals of stereoselectivity for the two enzymes.