Tannins and Related Polyphenols of Melastomataceous Plants. V. Three New Complex Tannins from Melastoma malabathricum L.
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چکیده
منابع مشابه
Tannins and related polyphenols of melastomataceous plants. VIII. Nobotanins L, M and N, trimeric hydrolyzable tannins from Tibouchina semidecandra.
Three hydrolyzable tannins, nobotannins L, M and N, were isolated from the water-soluble portion of the leaf extract of Tibouchina semidecandra, and their trimeric structures were elucidated from spectral and chemical evidence. Nobotanins L and N exist as equilibrium mixtures of four anomers due to the presence of two unacylated anomeric centers.
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Proanthocyanidins (PA) (condensed tannins) and hydrolyzable tannins (HT) are the two major classes of tannins. Proanthocyanidins are flavonoid polymers. Hydrolyzable tannins are polymers of gallic or ellagic acid esterified to a core molecule, commonly glucose or a polyphenol such as catechin. Proanthocyanidins are the most common type of tannin found in forage legumes. Problems in the analysis...
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ژورنال
عنوان ژورنال: Chemical and Pharmaceutical Bulletin
سال: 1992
ISSN: 0009-2363,1347-5223
DOI: 10.1248/cpb.40.1727