从傣药小灯台(Winchia catophylla A. DC.)中分到4个吲哚生物碱,经理化常数测定,光谱分析和化学转化,分别鉴定为echitamine chloride(Ⅰ),echitamidine(Ⅱ),N_b-demethyl-echitamine(Ⅲ)和22-O-acetyl-N_--demethyl-echitamine(Ⅳ),其...从傣药小灯台(Winchia catophylla A. DC.)中分到4个吲哚生物碱,经理化常数测定,光谱分析和化学转化,分别鉴定为echitamine chloride(Ⅰ),echitamidine(Ⅱ),N_b-demethyl-echitamine(Ⅲ)和22-O-acetyl-N_--demethyl-echitamine(Ⅳ),其中Ⅳ为新的吲哚生物碱。展开更多
Maytansine (I) (C34H46CIN3O10) is a novel type of ansa macrolide with potent antitumor activity. It was isolated by Kupchan et al. with great efforts from several Maytenus species (0.2 p.p.m.—1.5 p.p.m, dried plan...Maytansine (I) (C34H46CIN3O10) is a novel type of ansa macrolide with potent antitumor activity. It was isolated by Kupchan et al. with great efforts from several Maytenus species (0.2 p.p.m.—1.5 p.p.m, dried plant material) collected in Kenya and Ethiopia. It showed highly inhibitory activity against several experimental tumors (L-1210, P-388, W-256, S-180, Lewis lung carcinoma and B-16 melanocarcinoma) at the level of micrograms per kilogram body weight and the safety dosage ranging about 50—100 folds. Therefore, maytansine has been considered as one of the most promising anticancer agent of natural origin, attracting the interest of many relevant scientists.展开更多
文摘从傣药小灯台(Winchia catophylla A. DC.)中分到4个吲哚生物碱,经理化常数测定,光谱分析和化学转化,分别鉴定为echitamine chloride(Ⅰ),echitamidine(Ⅱ),N_b-demethyl-echitamine(Ⅲ)和22-O-acetyl-N_--demethyl-echitamine(Ⅳ),其中Ⅳ为新的吲哚生物碱。
文摘Maytansine (I) (C34H46CIN3O10) is a novel type of ansa macrolide with potent antitumor activity. It was isolated by Kupchan et al. with great efforts from several Maytenus species (0.2 p.p.m.—1.5 p.p.m, dried plant material) collected in Kenya and Ethiopia. It showed highly inhibitory activity against several experimental tumors (L-1210, P-388, W-256, S-180, Lewis lung carcinoma and B-16 melanocarcinoma) at the level of micrograms per kilogram body weight and the safety dosage ranging about 50—100 folds. Therefore, maytansine has been considered as one of the most promising anticancer agent of natural origin, attracting the interest of many relevant scientists.