Integrastatins: structure and HIV-1 integrase inhibitory activities of two novel racemic tetracyclic aromatic heterocycles produced by two fungal species

Integrastatins are two novel aromatic natural products derived from fungal fermentations who possess a novel [6/6/6/6]-ring system and are racemic despite having two asymmetric centers. These compounds inhibited the strand transfer reaction of HIV-1 integrase with IC50 values of 1.1–2.5 μM.