Globoidnan A: a lignan from Eucalyptus globoidea inhibits HIV integrase

The cyclolignan globoidnan A, which inhibits HIV integrase, was isolated from Eucalyptus globoidea. The structure of globoidnan A was solved by 2D NMR. An HTS campaign aimed at the identification of inhibitors of HIV integrase showed that the methanol extract from the buds of a Eucalyptus globoidea was active. Bioassay guided fractionation of this extract resulted in the purification and structural elucidation of the lignan, globoidnan A ( 1) as the only compound in the extract responsible for the inhibition of HIV integrase. The compound was found to inhibit the combined 3′ processing and strand transfer activity of HIV integrase with an IC 50 = 0.64 μM.