FREE-RADICAL STUDIES AND SOLUTIONS TO THE SYNTHESIS OF (-CYCLOPHELLITOL())

D-Xylose serves as a starting material for approaches to the synthesis of the glucosidase inhibitors, (+)-cyclophellitol (1) and (+)-epi-cyc lophellitol (2). An investigation of the cyclization of diastereomeric oxiranyl radicals to achieve this goal was moderately successful with the diastereomer that would have led to epi-cyclophellitol undergoing cyclization. An alternative route to cyclophellitol from D-xylose emp loyed Grubbs' ring closure metathesis and radical transformations to c omplete the synthesis.