Flavanones of Erythrina livingstoniana with antioxidant properties.

Six new flavanones ( 1 – 6 ), together with six known compounds were isolated from Erythrina livingstoniana . Their structures were elucidated on the basis of NMR data and HRMS n fragmentation pathway and by comparison with literature data. Compounds 5 , 7 and 8 showed remarkable DPPH free radical scavenging efficacies. The compounds, however, did not demonstrate an anti-inflammatory potential when tested using a PGE 2 (prostaglandin E2) competitive enzyme immunoassay. The plausible biosynthetic pathways of the isolated compounds are described. [ABSTRACT FROM AUTHOR]