A new C 22 polyacetylene and seven isoprenylated pterocarpans from Erythrina subumbrans .

A new C 22 polyacetylene, erysectol A ( 1 ), and seven isoprenylated pterocarpans, phaseollin ( 2 ), phaseollidin ( 3 ), cristacarpin ( 4 ), (3' R )-erythribyssin D/(3'S)-erythribyssin D ( 5a/5b ) and dolichina A/dolichina B ( 6a/6b ) were isolated from the twigs and leaves of Erythrina subumbrans. Their structures were determined based on their NMR spectral data. Except for 2 - 4 , all the other compounds were isolated from this plant for the first time. Erysectol A was the first reported C 22 polyacetylene from plants. Polyacetylene was isolated from Erythrina plants for the first time.