Prenylisoflavonoids from Erythrina senegalensis as Novel HIV-1 Protease Inhibitors

Abstract

Eight compounds were isolated from the CH(2)Cl(2) extracts of Erythrina senegalensis to assess HIV-1 protease (PR) activity inhibition. The prenylated isoflavone structures, identified by spectroscopic analysis, were 8-prenylluteone (1), auriculatin (2), erysenegalensein O (3), erysenegalensein D (4), erysenegalensein N (5), derrone (6), alpinumisoflavone (7), and 6,8-diprenylgenistein (8). The constituents showed dose-dependent inhibitory activities on HIV-1 PR with IC(50) values from 0.5 to 30.0 mu M. Compounds 1-5 possessing two hydroxy groups in the 2' and 4' positions of the B ring, potently inhibited HIV-1 PR activity. In addition, 6,8-diprenylgenistein (8) with two prenyl groups in the 6 and 8 positions of the A ring and one hydroxy group in the 4' position of B-ring was the most potent HIV-1 PR inhibitor.