Annonaceous acetogenins from the leaves of Annona montana.

A novel Annonaceous acetogenin, montanacin F, with a new type of terminal lactone unit, was isolated from the leaves of Annona montana. Its structure was determined on the basis of spectral evidences and chemical methods, and a possible biosynthetic pathway was discussed. In addition, the cytotoxicity of montanacin F was evaluated in vitro against Lewis lung carcinoma (LLC) tumor cell lines. Furthermore, the previously isolated cytotoxic acetogenin annonacin against LLC was examined for in vivo antitumor activity with LLC tumor cells.