New phenylethanoid glycosides from Cistanche tubulosa (SCHRENK) HOOOK. f. I.

Abstract

Four new phenylethanoid glycosides, tubulosides A (II), B (VI), C (VII) and D (VIII), have been isolated from Cistanche tubulosa (SCHRENK) HOOK. f. (Orobanchaceae), together with four known phenylethanoid glycosides, echinacoside (I), acteoside (III), acteoside isomer (IV) and 2'-acetylacteoside (V). The structures of II, VI, VII and VIII were established on the basis of chemical evidence and spectral data. Compounds VII and VIII possess a triacetylrhamnosyl moiety as the terminal sugar.