three bufadienolides by Nocardia sp. NRRL 5646 was investigated. Notably, resibufogenin was converted to 3-acetyl 15beta-hydroxyl bufotalin, via an unprecedented 14beta,15beta-epoxy ring cleavage and a regio-selective acetoxylation. This product showed significantly increased cytotoxic activity. The regio-selective acetylation of the 3-OH was also involved in the other reactions. The structures of metabolites
AbstractAn unexpected reaction of cinobufagin analogues in the presence of PPh3/I2 in EtOAc at room temperature to obtain diene compounds has been described. The whole process is carried out under mild conditions and the desired products are formed in good yields. It provides a simple, effective, and novel reaction method for the synthesis of diene compounds from corresponding substrates. Graphic abstract
摘要已经描述了烟蟾毒素类似物在PPh 3 / I 2存在下在室温下于EtOAc中的意外反应以获得二烯化合物。整个过程在温和的条件下进行,并以高收率形成所需的产物。它为从相应的底物合成二烯化合物提供了一种简单,有效和新颖的反应方法。 图形摘要
Kotake, Justus Liebigs Annalen der Chemie, 1928, vol. 465, p. 1,10, 11, 19
作者:Kotake
DOI:——
日期:——
Jensen; Chen, Journal of Biological Chemistry, 1930, vol. 87, p. 741,745, 748