作者:Edilberto R. Silveira、Maria JoséC. Falcão、Alisio Menezes、David G.I. Kingston、Thomas E. Glass
DOI:10.1016/0031-9422(95)00103-e
日期:1995.8
A chloroform extract of the roots of Bredemeyera floribunda yielded two new pentaoxygenated xanthones, 1,7-dihydroxy-3,4,8-trimethoxyxanthone and 1,3,7-trihydroxy-4,8-dimethoxyxanthone, and the ethanol extract of the resulting marc yielded 1,3,6-trihydroxy-2,7-dimethoxyxanthone. Structure determination of these pentaoxygenated xanthones was accomplished by spectral analysis, mainly NMR, including normal and inverse detection techniques such as HETCOR and HMBC. Chemical derivatization and comparison to literature data were also used.