Anti HIV-1 flavonoid glycosides from Ochna integerrima

Bioassay-guided fractionation of the anti-HIV-1 active EtCAc extract from leaves and twigs of Ochna integerrima led to the isolation of five new flavonoid glycosides 1-5, five known flavonoids 6-10, and two known flavonoid glycosides 11 and 12. Structures were determined based on spectroscopic analyses. 6-gamma,gamma-Dimethylallyidihydrokaempferol 7-O-beta-D-glucoside (1), 6-gamma,gamma-dimethylallylquercetin 7-O-beta-D-glucoside (3), 6-(3-hydroxy-3-methylbutyl)taxifolin 7-O-beta-D-glucoside (4), 6-(3-hydroxy-3-methylbutyl)quercetin 7-O-beta-D-glucoside (5), and 6-gamma,gamma-dimethylallyltaxifolin 7-O-beta-D-glucoside (11) showed anti-HIV-1 activities in the syncytium assay using the (Delta Tat/rev)MC99 virus and the 1A2 cell line system with EC50 values ranging from 14.0-102.4 mu g/mL. Furthermore, ochnaflavone 7 ''-O-methyl ether (7) and 2 '', 3 ' -dihydroochnaflavone 7 '' -O-methyl ether (8) were very active; they exerted activities in the syncytium assay with EC50 values 2.0 and 0.9 mu g/mL, respectively, and likewise inhibited HIV-1 reverse transcriptase (RT) with IC50 values of 2.0 and 2.4 mu g/mL, respectively.