Woodfordin C, a Macro-ring Hydrolyzable Tannin Dimer with Antitumor Activity, and Accompanying Dimers from Woodfordia fruticosa Flowers

Abstract

Three new dimeric hydrolyzable tannins, woodfordins A, B and C, along with seven known hydrolyzable tannins, including oenothein B, a dimer exhibiting marked host-mediated antitumor activity, were isolted from in Indonesian curde drug, Sidowayah [dried flowers of Woodfordia fruticosa (L.) KURZ (Lythraceae)]. The structures of the new tannins were elucidated based on chemical and spectral evidence. Woodfordin C, having a macro-ring structure, was also found to exhibit a significant antitumor activity.