Two oleanene glycosides from the aerial parts of Caltha polypetala

Two new oleanene glycosides (1-2) possessing hederagenin as the aglycone we re isolated from the methanolic extract of the aerial parts of Caltha polyp etala together with four known glycosides. The saccharide portion linked to C-3 of the aglycone is made up of alpha-L-arabinopyranose, alpha-L-rhamnop yranose and galactopyranose in the new compounds; while compound 1 possesse s linked to C-28 a trisaccharide moiety made up of two beta-D-glucopyranose and one alpha-L-rhamnopyranose unit, in compound 2 the 28-COOH group is fr ee. The structures were elucidated by 1D and 2D NMR experiments including H -1-H-1 (DQF-COSY, 1D-TOCSY, 2D-ROESY) and H-1-C-13 (HSQC, HMBC) spectroscop y. (C) 1999 Elsevier Science Ltd. All rights reserved.