Four new ursane-type saponins from Morina nepalensis var. alba

✍ Scribed by Rong Wei Teng; Hong Yan Xie; De Zu Wang; Chong Ren Yang

• Publisher: John Wiley and Sons
• Year: 2002
• Tongue: English
• Weight: 119 KB
• Volume: 40
• Category: Article
• ISSN: 0749-1581
• DOI: 10.1002/mrc.1060

✦ Synopsis

Abstract

Four new ursane‐type saponins, monepalosides C–F, together with a known saponin, mazusaponin II, were isolated from Morina nepalensis var. alba Hand.‐Mazz. Their structures were determined to be 3‐O‐α‐L‐arabinopyranosyl‐(1 → 3)‐&[alpha;‐L‐rhamnopyranosyl‐(1 → 2)]‐α‐L‐arabinopyranosylpomolic acid 28‐O‐β‐D‐glucopyranosyl‐(1 → 6)‐β‐D‐glucopyranoside (monepaloside C, 1), 3‐O‐α‐L‐arabinopyranosyl‐(1 → 3)‐&[alpha;‐L‐rhamnopyranosyl‐(1 → 2)]‐β‐D‐xylopyranosylpomolic acid 28‐O‐β‐D‐glucopyranosyl‐(1 → 6)‐β‐D‐glucopyranoside (monepaloside D, 2), 3‐O‐α‐L‐arabinopyranosyl‐(1 → 3)‐&[beta;‐D‐glucopyranosy‐(1 → 2)]‐α‐L‐arabinopyranosylpomolic acid 28‐O‐β‐D‐glucopyranosyl‐(1 → 6)‐β‐D‐glucopyranoside (monepaloside E, 3) and 3‐O‐β‐D‐xylopyranosylpomolic acid 28‐O‐β‐D‐glucopyranoside (monepaloside F, 4) on the basis of chemical and spectroscopic evidence. 2D NMR techniques, including ^1^H–^1^H COSY, HMQC, 2D HMQC‐TOCSY, HMBC and ROESY, and selective excitation experiments, including SELTOCSY and SELNOESY, were utilized in the structure elucidation and complete assignments of ^1^H and ^13^C NMR spectra. Copyright © 2002 John Wiley & Sons, Ltd.