AbstractAdditional bioactive Annonaceous acetogenins have been isolated from the EtOH extract of the bark ofAnnona bullataRich. by bioactivity‐directed fractionation using lethality to brine shrimp. These acetogenins include bullatencin, a new single tetrahydrofuran acetogenin having a double bond in the hydrocarbon chain; 4‐deoxyasimicin, a new adjacent bis‐tetrahydrofuran acetogenin; and the uvariamicins, an isomeric mixture of four single tetrahydrofuran acetogenins. These acetogenins showed selective cytotoxicities for certain human solid tumor cell lines comparable to or better than adriamycin. © 1992 Wiley‐L