New 29-nor-cycloartanes with a 3,4-seco- and a novel 2,3-seco-structure from the leaves of Sinocalycanthus chinensis
作者:Yoshiki Kashiwada、Kazuya Nishimura、Shin-ichiro Kurimoto、Yoshihisa Takaishi
DOI:10.1016/j.bmc.2011.03.055
日期:2011.5
Eight new triterpenoids, including sinocalycanchinensins A-E (1-5) with a 3,4-seco-29-nor-cycloartane skeleton, sinocalycanchinensin F (6) possessing a novel 2,3-seco-29-nor-cycloartane skeleton, and 29-nor-cycloartanes, sinocalycanchinensins G and H (7 and 8), have been isolated from the leaves of Sinocalycanthus chinensis. Their structures were elucidated on the basis of spectroscopic examinations. The cytotoxicities of the isolated new triterpenes against a panel of human cancer cell lines, including multi-drug resistant (MDR) cancer cell lines, were also evaluated. Compound 5 demonstrated enhanced cytotoxicity against MDR KB cells in the presence of colchicine, although all the compounds showed moderate or no cytotoxicities. (C) 2011 Elsevier Ltd. All rights reserved.