Total Synthesis of Phenanthro-Quinolizidine Alkaloids: (±)-Cryptopleurine, (±)-Boehmeriasin A, (±)-Boehmeriasin B and (±)-Hydroxycryptopleurine
作者:Mingbo Cui、Qingmin Wang
DOI:10.1002/ejoc.200900834
日期:2009.11
The first synthesis of (±)-boehmeriasin A and B and a concise synthesis of (±)-cryptopleurine and (±)-hydroxycryptopleurine are described. The piperidine ring of these alkaloids was constructed by the coupling of the phenanthrene ring with 2-bromopyridine through a nucleophilic substitution reaction and subsequent reduction of the resulting pyridyl ketone. The first crystal structure of a phenanthro-quinolizidine
Two new phenanthroquinolizidine alkaloids, boehmeriasins A and B, were isolated from the aqueous ethanolic extract of Boehmeria siamensis Craib (Urticaceae) by bioassay-guided fractionation. Their structures were elucidated on the basis of spectral evidence. Boehmeriasin A possesses cytotoxic activity against 12 cell lines from 6 panels of cancer including lung cancer, colon cancer, breast cancer, prostate cancer, kidney cancer and leukemia with GI50 between 0.2 and 100 ng/mL, whereas boehmeriasin B showed lower activity.
通过生物测定指导分馏法,从荨麻科植物苧麻(Boehmeria siamensis Craib)的乙醇水提取物中分离出了两种新的蒽醌类生物碱--苧麻素 A 和 B。根据光谱证据阐明了它们的结构。苧麻素 A 对 6 种癌症(包括肺癌、结肠癌、乳腺癌、前列腺癌、肾癌和白血病)的 12 种细胞株具有细胞毒活性,GI50 在 0.2 至 100 ng/mL 之间,而苧麻素 B 的活性较低。