Prenylated flavonoids from Deguelia hatschbachii and their systematicsignificance in Deguelia

摘要

Chemical investigation of dichloromethane and petrol extracts from the roots of D. hatschbachii A. M. G. Azevedo furnished thirteen compounds from which five are described for the first time and their structures were determined to be 3-(4 ' -hydroxyphenyl)-5-methoxy-6-(3,3-dimethylallyl)2 " ,2 " -dimethylchromene-(5 " ,6 " :8,7)-3-(propyl-2-one)-4H-1-benzo-2,3-dihydropyran-2,4-dione; 6,4 ' -dihydroxy-3-(3,3-dimethylallyl)-2 " ,2 " -dimethylchromene (5 " ,6 ". 5,4)-2-methoxy deoxybenzoin; 6,4 ' -dihydroxy-3-(3,3-dimethylallyl)-2 " ,2 " -dimethylchromene (5 " ,6 " :5,4)-2-methoxy-8-(propyl-2-one) deoxybenzoin; 6-(3,3-dimethylallyl)-2 " ,2 " -dimethylchromene (5 " ,6 " :4,5)-4 ' -hydroxy-3-methoxy stilbene and 3,5-dimethoxy-4 ' -hydroxy-4-(3,3-dimethylallyl) stilbene by spectral analysis (UV, IR, MS and 1D- and 2D- NMR experiments). The root extracts and some isolated compounds were bioactive, as revealed by bioautography and brine shrimp lethality assays.