The extractives of Heliopsis scabra: constitution of two new lignans
Abstract
The structures of two new lignan constituents of Heliopsis scabra, helianthoidin and helioxanthin, have been determined by spectral and degradative work. The former is shown to be 2-angelyloxy-2-piperonyl-3-veratryl-2S,3S-γ-butyrolactone (I), and the latter 1-(3,4-methylenedioxyphenyl)-2-hydroxymethyl-7,8-methylenedioxy-3-naphthoic acid lactone (XVII).