Isolation of an anti-HIV diprenylated bibenzyl from Glycyrrhiza lepidota

The organic soluble extract from the leaves of Glycyrrhiza lepidota showed moderate activity in the US National Cancer Institute in vitro anti-HIV-1 bioassay. Chromatographic separation of this extract resulted in the identification of a new diprenylated bibenzyl as the compound responsible for the observed anti-viral activity. Extensive spectroscopic experiments provide the complete 1H NMR and 13C NMR spectral assignments to support the proposed structure. Known compounds glepidotin B and glepidotin A were also isolated from the extract and shown to be inactive in the anti-viral assay. The diprenylated bibenzyl 1 was isolated from Glycyrrhiza lepidota. Its structural elucidation and biological activity against HIV-1 are reported.