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2005

Turkish Journal of Chemistry

Flavonol glycosides

Articles 1 - 2 of 2

Full-Text Articles in Physical Sciences and Mathematics

Flavonol Glycosides From Asperula Arvensis L., Zühal Güvenalp, L. Ömür Demi̇rezer Jan 2005

Flavonol Glycosides From Asperula Arvensis L., Zühal Güvenalp, L. Ömür Demi̇rezer

Turkish Journal of Chemistry

From the aerial parts of Asperula arvensis L. 9 known flavonol glycosides, namely quercetin (1), isoquercitrin [= quercetin 3-O-\beta-glucopyranoside] (2), hyperin [= quercetin 3-O-\beta -galactopyranoside] (3), quercetin 7-O-\beta-galactopyranoside (4), quercetin 4'-O-\beta-galactopyranoside (5), isorhamnetin 3-O-\beta -galactopyranoside (6), isorhamnetin 5-O-\beta-galactopyranoside (7), dihydrokaempferol 7-4'-dimethylether 3-O-\beta -glucopyranoside (8) and isorhamnetin 3-O-\alpha -rhamnopyranosyl (1''' \to 6'')-\beta -glucopyranosid (9), were isolated. The structures of the compounds were elucidated by high field 1D and 2D NMR and ESI-MS spectroscopies.


Polyphenolic Compounds And Antimicrobial Activity Of Quercus Aucheri Leaves, Mahmut Koray Sakar, Di̇dem Şöhretoğlu, Meral Özalp, Meli̇ke Eki̇zoğlu, Sonia Piacente, Cosimo Pizza Jan 2005

Polyphenolic Compounds And Antimicrobial Activity Of Quercus Aucheri Leaves, Mahmut Koray Sakar, Di̇dem Şöhretoğlu, Meral Özalp, Meli̇ke Eki̇zoğlu, Sonia Piacente, Cosimo Pizza

Turkish Journal of Chemistry

Chromatographic studies (CC, VLC, MPLC, and PTLC) on ethyl acetate extract from the leaves of Quercus aucheri yielded 2 flavonoids (quercetin 3-O-\alpha-L-arabinopyranoside (1), quercetin 3-O-\beta-D-galactopyranoside (2)) and 2 tannin precursors and a procyanidin [(isolated as peracetates of (+)-catechin (3a), (+)-gallocatechin (4a) and epicatechin-(4\beta \to 8)-catechin (5a))]. The structures of the compounds were elucidated by UV, 1D-NMR (^1H, ^{13}C, TOCSY) and 2D-NMR (COSY, HSQC, HMBC) techniques. Different extracts (80% MeOH, EtOAc, n-BuOH and H_2O) from the leaves of Q. aucheri were investigated for their antimicrobial activity against 2 Gram-positive and 2 Gram-negative bacteria and 3 yeast-like fungi by a broth microdilution …