Asitrilobins C and D: two new cytotoxic mono-tetrahydrofuran annonaceous acetogenins from Asimina triloba seeds.

Two new bioactive mono-tetrahydrofuran (THF) gamma-lactone acetogenins, asitrilobins C (1) and D (2), were isolated from the seeds of Asimina triloba (Annonaceae) by directing the fractionation with brine shrimp lethality. Compounds 1 and 2 have a relative stereochemical relationship of threo/trans/threo across the mono-THF ring with its two flanking hydroxyls. Their structures were established on the basis of chemical and spectral evidence. Compounds 1 and 2 showed selective cytotoxicity comparable with adriamycin for the breast carcinoma (MCF-7) and the colon adenocarcinoma (HT-29) cell lines.