Two new isoflavanoids from Bolusanthus Speciosus

Abstract

The structures of two new isoflavonoids from the combined ethyl acetate/methanolic extracts of the stem bark of Bolusanthus speciosus have been established as 4,7,2' -trihydroxy-4' -methoxyisoflavanol (1) and 5,7,3' ,4' -tetrahydroxy-5' -(2-epoxy-3-methylbutyl)isoflavanone (2). Five other known isoflavonoids, 5,7,3' -trihydroxy-4' -methoxy-5' -γγ; -dimethylallylisoflavanone, 5,7,2' -trihydroxy-4' -methoxy-6,5' -di)(γγ -dimethylallyl)isoflavanone, 5,7,2' ,4'-tetrahydroxy-8,5'2; -di(γγ -dimethylallyl)flavanone, 5,7,2' ,4' -tetrahydroxy-8,3' -di(γγ -dimethylallyl)-isoflavanone, and derrone were also isolated. Compound 2 showed moderate activity against gram positive bacteria and weak activity against gram negative bacteria, while compound 1 was weakly active against both organisms in a TLC bioautography assay.