Isolation of linobiflavonoid, a novel biflavonoid from Linostoma pauciflorum Griff

A novel biflavonoid, that we have named linobiflavonoid, and the known biscoumarin ether, daphnoretin, were isolated from the root extracts of Linostoma pauciflorum Griff. The structure of linobiflavonoid was determined from interpretation of its NMR spectroscopic data and from a comparison of this data with those of known biflavonoids and biflavones. The known flavones, 5,4'-dihydroxy- 7,3',5'-trimethoxyflavone and 5,4'-dihydroxy-7-methoxyflavone along with stigmasterol were isolated from the vines of the same plant. 4'-Dihydroxy-7,3'-5'-trimethoxyflavone was active against Mycobacterium tuberculosis (MIC 3.13 mu M) and KB-oral cavity cancer (IC50 17.41 mu M). (C) 2011 Phytochemical Society of Europe. Published by Elsevier B.V. All rights reserved.