Ypsilandrosides U-Y, five new steroidal saponins from Ypsilandra thibetica

Abstract

Abstract Phytochemical reinvestigation on the whole plants of Ypsilandra thibetica obtained four new spirostanol glycosides, named ypsilandrosides U-X (1–4), and one new cholestanol glycoside, named ypsilandroside Y (5). Their structures have been established by extensive spectroscopic data and chemical methods. Among them, compound 4 is a rare spirostanol glycoside which possesses a novel 5(6 → 7) abeo-steroidal aglycone, while compound 1 is a first spirostanol bisdesmoside attached to C-3 and C-12, respectively, isolated from the genus Ypsilandra. The induced platelet aggregation activity of the isolates was tested. Graphical Abstract

Keywords

• Ypsilandra thibetica
• Melanthiaceae
• Ypsilandrosides U-Y
• Spirostanol saponins
• Cholestanol saponins