Isolation and Structure Elucidation of an Isoflavone and a Sesterterpenoic Acid from <i>Henriettella </i><i>f</i><i>ascicularis</i>
2002-10-11T00:00:00Z (GMT) by
A new isoflavone, 4‘,5,7-trihydroxy-6,8-dimethylisoflavone (<b>1</b>), and a new sesterterpenoic acid (<b>2</b>), together with five known compounds, lichexanthone (<b>3</b>), (−)-pinoresinol (<b>4</b>), betulinic acid, palmitic acid, and β-sitosterol, were isolated from a dichloromethane extract of the branches of <i>Henriettella fascicularis.</i> Their structures were established by extensive spectroscopic methods. An attempt to determine the absolute stereochemistry of (2<i>E</i>,6<i>S</i>)-6-[(1<i>R</i>,5<i>Z</i>,3a<i>S</i>,9<i>R</i>,10<i>Z</i>,12a<i>R</i>)-1,2,3,3a,4,7,8,9,12,12a-decahydro-9-hydroxy-3a,6,10-trimethylcyclopentanocycloundecen-1-yl]-2-methylhept-2-enoic acid (<b>2</b>) was performed by single-crystal X-ray analysis, using Cu Kα radiation. Compound <b>1</b> showed significant competitive binding to estrogen receptor β and moderate antiestrogenic activity with cultured Ishikawa cells.