[Chemical constituents of Camellia sinensis var. assamica]
Hong-Bo Zhu1, Bao-Min Li, Chao Liu
1State Key Laboratory of Bioactive Substance and function of Natural Medicines, Ministry of Education, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China. flybigbear@126.com
Abstract:
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.
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