Anti-plasmodial flavonoids from the stem bark of Erythrina abyssinica

Abstract

The ethyl acetate extract of the stem bark of Erythrina abyssinica showed anti-plasmodial activity against the chloroquine-sensitive (D6) and chloroquine-resistant (W2) strains of Plasmodium falciparum with IC50 values of 7.9 ± 1.1 and 5.3 ± 0.7 μg/ml, respectively. From this extract, a new chalcone, 2′,3,4,4′-tetrahydroxy-5-prenylchalcone (trivial name 5-prenylbutein) and a new flavanone, 4′,7-dihydroxy-3′-methoxy-5′-prenylflavanone (trivial name, 5-deoxyabyssinin II) along with known flavonoids have been isolated as the anti-plasmodial principles. The structures were determined on the basis of spectroscopic evidence.