Furostanol saponins and quercetin glycosides from the leaves of Helleborus viridis L.
Phytochemical analysis of the polar extracts of the leaves of Helleborus viridis (Ranunculaceae) resulted in the isolation of two new furostanol saponins (25R)-26-[(alpha-L-rhamnopyranosyl)oxy]-22alpha-methoxyfurost-5-en-3beta-yl O-beta-D-glucopyranosyl-(1-->3)-O-[6-acetyl-beta-D-glucopyranosyl-(1-->3)]-O-beta-D-glucopyranoside (1) and (25R)-26-[(alpha-L-rhamnopyranosyl)oxy]-22alpha-methoxyfurost-5-en-3beta-yl O-beta-D-glucopyranosyl-(1-->3)-O-beta-D-glucopyranosyl-(1-->3)-O-beta-D-glucopyranoside (2) and three new quercetin glycosides, quercetin 3-O-(2-E-caffeoyl)-alpha-L-arabinopyranosyl-(1-->2)-beta-D-galactopyranoside-7-O-beta-d-glucopyranoside (3), quercetin 3-O-(2-E-caffeoyl)-alpha-L-arabinopyranosyl-(1-->2)-beta-D-galactopyranoside (4), and quercetin 3-O-alpha-L-arabinopyranosyl-(1-->2)-beta-D-galactopyranoside (5). The structures of the new compounds were determined by spectroscopic analysis, including 2D NMR data and mass spectrometry.
Braca
Alessandra
A
Dipartimento di Chimica Bioorganica e Biofarmacia, Università di Pisa, Via Bonanno 33, 56126 Pisa, Italy.
Prieto
Josè Maria
JM
De Tommasi
Nunziatina
N
Tomè
Franca
F
Morelli
Ivano
I
D039322:Helleborus / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D015394:Molecular Structure; D018515:Plant Leaves / Q000737:chemistry; D011794:Quercetin / Q000031:analogs & derivatives* / Q000302:isolation & purification*; D012503:Saponins / Q000302:isolation & purification*
D012503:Saponins; D011794:Quercetin