Extracts of 41 medicinal plants used in Egyptian folk medicine were screened for their inhibitory effects on human immunodeficiency virus-1 reverse transcriptase. The extracts of fruits of Phyllanthus emblica, Quercus pedunculata, Rumex cyprius, Terminalia bellerica, Terminalia chebula and Terminalia horrida showed significant inhibitory activity with IC50 < or = 50 micrograms/ml. Through a bioassay guided-fractionation of the methanol extract of the fruit of P. emblica, putranjivain A (1) was isolated as a potent inhibitory substance with IC50 = 3.9 microM, together with 1,6-di-O-galloyl-beta-D-glucose (2), 1-O-galloyl-beta-D-glucose (3), kaempferol-3-O-beta-D-glucoside (4), quercetin-3-O-beta-D-glucoside (5) and digallic acid (6). The inhibitory mode of action by 1, 2 and 6 was non-competitive with respect to the substrate but competitive with respect to a template-primer. Furthermore, the stereochemistry of 1 was established in this paper by nuclear magnetic resonance spectroscopy.

In an attempt to find out new, potent and safe anti-inflammatory molecules and as a contribution in the chemistry of triterpenes, a series of 18β-glycyrrhetinic acid (GTA) derivatives (4a–j, 5a–e, 7–9, 11–13) were synthesized and evaluated as anti-inflammatory agents using carrageenan induced rat paw edema method. The synthesized derivatives proved superior anti-inflammatory activity to GTA. Moreover, some of the produced derivatives demonstrated higher effect than prednisolone and indomethacin. This remarkable anti-inflammatory effect was combined with no detrimental effect on the gastrointestinal tract (GIT) of the test rats. All of the synthesized compounds were characterized by NMR spectroscopy and high-resolution ESI mass spectrometry