Tannins and related compounds. XLVIII Rhubarb. 7 Isolation and characterization of new dimeric and trimeric procyanidins.
作者:YOSHIKI KASHIWADA、GEN-ICHIRO NONAKA、ITSUO NISHIOKA
DOI:10.1248/cpb.34.4083
日期:——
Together with the known flavan-3-ols and procyanidins, a new procyanidin dimer (11) and several new trimers (14, 15, 16, 20, 22, 24 and 26) have been isolated from high-quality rhubarb ( ?? ?? ?? ). On the basis of chemical and spectroscopic data, the structures of these compounds were characterized as procyanidin B-5 3, 3'-di-O-gallate (11), procyanidin C-1 3', 3''-di-O-gallate (14), procyanidin C-1 3, 3', 3''-tri-O-gallate (15), 3-O-galloylepicatechin-(4β→6)-3-O-galloylepicatechin-(4β→8)-3-O-galloylepicatechin (20), 3-O-galloylepicatechin-(4β→6)-3-O-galloylepicatechin-(4β→6)-3-O-galloylepicatechin (22), 3-O-galloylepicatechin-(4β→6)-3-O-galloylepicatechin-(4β→8)-catechin (26), 3-O-galloylepicatechin-(4β→8)-3-O-galloylepicatechin-(4β→8)-catechin (16) and 3-O-galloylepicatechin-(4β→8)-3-O-galloylepicatechin-(4β→6)-catechin (24).
与已知的黄烷-3-醇和原花青素一起,从优质大黄 (?? ? ??)。根据化学和光谱数据,这些化合物的结构被表征为原花青素 B-5 3, 3'-二-O-没食子酸酯 (11)、原花青素 C-1 3', 3''-二-O-没食子酸酯 (14)、原花青素 C-1 3, 3', 3''-三-O-没食子酸酯 (15)、3-O-没食子酰儿茶素-(4β→6)-3-O-没食子酰儿茶素-(4β→8) -3-O-没食子酰儿茶素 (20)、3-O-没食子酰儿茶素-(4β→6)-3-O-没食子酰儿茶素-(4β→6)-3-O-没食子酰儿茶素 (22)、3-O-没食子酰儿茶素-( 4β→6)-3-O-没食子酰儿茶素-(4β→8)-儿茶素 (26), 3-O-没食子酰儿茶素-(4β→8)-3-O-没食子酰儿茶素-(4β→8)-儿茶素 (16)和 3-O-没食子酰儿茶素-(4β→8)-3-O-没食子酰儿茶素-(4β→6)-儿茶素 (24)。