Gneyulins A and B, Stilbene Trimers, and Noidesols A and B, Dihydroflavonol-C-Glucosides, from the Bark of Gnetum gnemonoides

Gneyulins A (1) and B (2), two new stilbene trimers consisting of oxyresveratrol constituent units, and noidesols A (3) and B (4), two new dihydroflavonol-C-glucosides, were isolated from the bark of Gnetum gnemonoides. The structures and configurations of 1−4 were elucidated on the basis of 2D NMR correlations and X-ray analysis. Gneyulins A (1) and B (2) showed inhibition of Na⁺-glucose transporters (SGLT-1 and SGLT-2).