During the present report period, a number of new anti-HIV chemotypes have been identified. Anti-HIV bioassay-guided fractionation of extracts from the Australian shrub Conospermum sp. yielded a novel trimeric quinone derivative. Extracts from the tropical rainforest tree Calophyllum lanigerum provided eight new prenylated coumarin derivatives. Extracts of related Calophyllum species were also found to contain related anti-HIV coumarins. A series of related, polyisoprenylated benzophenone compounds which inhibit HIV were isolated from Symphonia globulifera, Garcinia livingstonei, Garcinia ovalifolia and Clusia rosea. These tropical plants are all members of the family Guttiferae. A member of the genus Chassalia provided an aqueous soluble metabolite that inhibits in vitro HIV infection. This compound has a relatively high molecular weight (3000-4000 daltons) and appears to have a unique structure.
