PHOSPHOLIPASE A(2) INHIBITORS FROM AN ERYTHRINA SPECIES FROM SAMOA

Three flavonoid phospholipase A(2) (PLA(2)) inhibitors were isolated f rom a MeOH extract of the bark of the Samoan medicinal plant Erythrina variegata. Two of these compounds, 4'-hydroxy-3',5'-diprenylisoflavon one (abyssinone V) (1) and 3,9-dihydroxy-2,10-diprenylpterocarp-6a-ene (erycrystagallin) (3), have been previously reported as antimicrobial agents from plants belonging to other Erythrina species. The isoflavo none 4'-hydroxy-6,3',5'-triprenylisoflavonone (2) is a new compound, a nd its structure was determined by spectroscopic techniques. The IC50 values for the PLA(2) enzyme were 6, 10, and 3 mu M for 1-3, respectiv ely.