Synthesis of diosgenyl α-l-rhamnopyranosyl-(1→2)-[β-d-glucopyranosyl-(1→3)]-β-d-glucopyranoside (gracillin) and related saponins

Diosgenyl α-l-rhamnopyranosyl-(1→2)-[β-d-glucopyranosyl-(1→3)]-β-d-glucopyranoside (gracillin), a monodesmosidic saponin isolated from paris, dioscorea, and costacea species with promising cardiovascular and antitumor activities, was synthesized by stepwise glycosylation.