epiafzelechin and epicatechin-gallate

To study the chemical constituents of Camellia sinensis var. assamica. The compounds were isolated by NKA Macroporous resin silica gel, Sephadex LH-20, RP-C18 column chromatographies and semi-preparative HPLC,and their structures were elucidated by physicochemical properties and spectral analysis. Thirteen compounds were isolated and identified as caffeine (1), theobromine (2), gallic acid (3), (+)-catechin (4), ampelopsin (5), (-)-epicatechin (6), (-)-epiafzelechin (7), (-)-epicatechin-3-O-gallate (8), (-)-epiafzelechin-3-O-gallate (9) , (+)-catechin-3-O-gallate (10) , (+)-afzelechin-3-O-gallate (11), quemefin-3-O-alpha-L-arabinopyranosid (12), and (-)-epicatechin-3-O-p-hydroxybenzoate (13). Compounds 2, 5, 10-13 were isolated from this plant for the first time, and compound 11 is a new natural product.

Topics: Camellia sinensis; Catechin; Chromatography, High Pressure Liquid; Flavonoids