title: Two new acetylated flavonoid glycosides from Centaurium spicatum L.
abstract: Two new acetylated flavonol glycosides, quercetin 3-O-[(2,4-diacetyl-α-L-rhamnopyranosyl)-(1→6)]-2,4-diacetyl-β-D-galactopyranoside (1) and quercetin 3-O-[(2,4-diacetyl-α-L-rhamnopyranosyl)-(1→6)]-3,4-diacetyl-β-D-galactopyranoside (2), in addition to two known acetylated quercetin glycosides quercetin 3-O-[(2,3,4-triacetyl-α-L-rhamnopyranosyl)-(1→6)-β-D-galactopyranoside (3) and quercetin 3-O-[(2,3,4-triacetyl-α-L-rhamnopyranosyl)-(1→6)-3-acetyl-β-D-galactopyranoside (4), were isolated from the aerial part of Centaurium spicatum (L.) Fritsch (Gentianaceae). Structure elucidation, especially the localization of the acetyl groups, and complete (1)H and (13)C NMR assignments of these biologically active compounds were carried out using one- and two-dimensional NMR measurements, including (1)H- and (13)C-NMR, DEPT-135, H-H COSY, HMQC and HMBC, in addition to HR-FAB/MS experiments.
authors: Pharmacognosy and Chemistry of Natural Products, School of Pharmaceutical Sciences, Kanazawa University, Kanazawa 920-1192, Japan.
authors: Ahmed E
authors: AE
authors: Allam
authors: Mohamed A
authors: MA
authors: El-Shanawany
authors: Enaam Y
authors: EY
authors: Backheet
authors: Alaa M
authors: AM
authors: Nafady
authors: Fumihide
authors: F
authors: Takano
authors: Tomihisa
authors: T
authors: Ohta
mesh_terms: D000107:Acetylation; D029966:Centaurium / Q000737:chemistry*; D005419:Flavonoids / Q000737:chemistry*; D006027:Glycosides / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure
chemical_list: D005419:Flavonoids; D006027:Glycosides