New Antifungal Terpenoid Glycosides from Alibertia edulis (Rubiaceae)

Phytochemical investigation from the stems of Alibertia edulis led to the isolation and identification of a new iridoid 6 β ‐hydroxy‐7‐epigardoside methyl ester ( 1 ) and a new saponin 3 β ‐ O ‐[ α ‐ L ‐rhamnopyranosyl‐(1→2)‐ O‐β ‐ D ‐glucopyranosyl‐(1→2)‐ O‐β ‐ D ‐glucopyranosyl]‐28‐ O‐β‐ D ‐glucopyranoside pomolate ( 2 ), along with three known compounds, shanzhiside methyl ester ( 3 ), ixoside ( 4 ), and 3,4,5‐trimethoxyphenyl 1‐ O ‐ β ‐ D ‐apiofuranosyl‐(1→6)‐ O‐β ‐ D ‐glucopyranoside ( 5 ). The structures of 1 and 2 were established on the basis of their spectroscopic data. Iridoid 1 and saponin 2 exhibited moderate inhibitory activities against Candida albicans and C. krusei in a dilution assay.