| Abstract: | Five new cardenolides and one new cardiac aglycone, i.e., (5α)‐sarmentogenin 3‐(α‐L ‐rhamnopyranoside) ( 1 ), (5α)‐sarmentogenin ( 2 ), 11‐oxouzarigenin 3‐(α‐L ‐rhamnopyranoside) ( 3 ), (5α)‐gitoxigenin 3‐(α‐L ‐rhamnopyranoside) ( 4 ), (5α)‐oleandrigenin 3‐(α‐L ‐rhamnopyranoside) ( 5 ), and (5α)‐oleandrigenin 3‐β‐D ‐glucopyranosyl‐(1 → 4)‐α‐L ‐rhamnopyranoside] ( 6 ), together with two known cardenolides, i.e., frugoside (= (3β,5α)‐3‐(6‐deoxy‐β‐D ‐allopyranosyl)oxy]‐14,19‐dihydroxycard‐20(22)‐enolide) and (17α)‐ascleposide (= (3β,5α,17α)‐3‐(6‐deoxy‐α‐D ‐allopyranosyl)oxy]‐14‐hydroxycard‐20(22)‐enolide), were isolated from the stem bark of Trewia nudiflora L. (Euphorbiaceae) collected in Xishuangbanna, Yunnan Province, China. Their structures were established by spectroscopic studies. Cardenolides were first found in the genus Trewia (Euphorbiaceae). |
