Prochirality transfer in the enzymic conversion of (E)-[4′-13C]-(6aS, 12aS)-Rot-2′-enonic acid into (6aS,12aS)-degulin: restricted stereoselectivity in an electro-cyclisation

Abstract

(E)-[4′-¹³C]-(6aS,12aS)-Rot-2′-enonic acid is enzymically converted into deguelin stereoselectively, but not stereospecifically [73%(6aS,12aS,6′pro-R); 27%(6aS,12aS,6′pro-S)], chemical conversion giving, within experimental error, equal amounts of (6aS,12aS,6′pro-S) and (6aS,12aS,6′pro-R); the stereochemistry of electrocyclisation in an enzymic situation is discussed.