Inhibition of HIV-1 integrase by galloyl glucoses from Terminalia chebula and flavonol glycoside gallates from Euphorbia pekinensis

The bioassay-directed isolation of Terminalia chebula fruits afforded four human immunodeficiency virus type 1 (HIV-1) integrase inhibitors, gallic acid (1) and three galloyl glucoses (2-4). In addition, four flavonol glycoside gallates (5-8) from Euphorbia pekinensis containing the galloyl moiety also showed the inhibitory activity at a level comparable to those of 2-4. By comparison with the activities of the compounds not bearing this moiety, it is proposed that the galloyl moiety plays a major role for inhibition against the 3'-processing of HIV-1 integrase of these compounds.