Bioactive tetrahydrofuran lignans from roots, stems, leaves and twigs of Anogeissus rivularis

Four previously undescribed tetrahydrofuran lignans, named anorisols A-D (1-4) and fourteen known compounds (5-18) were isolated from the roots, stems, leaves and twigs of Anogeissus rivularis. The chemical structures were elucidated on the basis of their spectroscopic data and by comparison with the literature data. The absolute configurations of 1-4 were established by comparison of the experimental ECD spectra with the calculated ECD spectra. Some isolated compounds were evaluated for their cytotoxic activity as well as anti-HIV1 activity employing reverse transcriptase (RT) and syncytium reduction assays using the Delta Tat/RevMC99 virus in 1A2 cell line systems. Compound 6 displayed the most potent activity in syncytium inhibition assay with effective concentration at 50% (EC50) value of 13.3 mu M (SI >3.0). In the reverse transcriptase assay, compound 1 exhibited moderate activity with IC50 value of 213.9 mu M.

Automated summary

Four new tetrahydrofuran lignans, named anorisols A-D, and fourteen known compounds were isolated from different parts of Anogeissus rivularis. The chemical structures were elucidated through spectroscopic data and comparison with literature data, and the absolute configurations were determined using experimental and calculated ECD spectra. Compound 6 showed the most potent activity in syncytium inhibition assay, and compound 1 exhibited moderate activity in the reverse transcriptase assay.