An enantiomerically and diastereomerically pure route has been developed fo
r the asymmetric synthesis of (1R, 2R,3R, 7aS)-trihydroxylated pyrrolizidin
e alkaloid, 7-deoxyalexine, featuring the stereocontrolled elaboration of t
he functionalized homochiral lactam derived from 2,3,5-tri-O-benzyl-beta-D-
arabinofuranose.