| In order to discover new antitumor agents from the plant sources, G. donnaiensis Finet et Ganept, a Goniothalamus species (Annonaceae) growing in Guangxi Zhuang autonomous region, was subjected to phytochemical studies. 31 compounds were isolated, among which 18 were new constituents including 17 new annonaceous acetogenins and a cyclopeptide. Their structures and most of the stereochemistries were elucidated by means of various modern spectroscopic techniques and chemical derivatization.Among the new acetogenins, there were seven pairs of epimers named goniodonins A~G (1-7) and 34-epi-goniodonins A~G (l'~7'), which were the first acetogenins discovered bearing a unique structural feature — lactol. A unusual C-4-acetoxyl group were presented in goniodonins F, G (6, 7) and 34-epi-goniodonins F, G (6', 7'). The other three new acetogenins were named goniodonins H~J (8-10). Goniodonin H was the first new acetogenin bearing a hydroxylated THF ring. Goniodonins I, J were new acetogenins having neither THF (epoxide) rings nor double bonds and prossessing only one or two vicinal diol (s) and isolated hydroxyls in the hydrocarbon chain. Another new compound was a cyclopeptide named goniodocin (21) consisting of six leucine (Leu), one isoleucine (Ile), one proline (Pro) and one valine (Val). The position of the He have not been definitely determined yet.The known compounds isolated from G. donnaiensis were 2,4-cis- and trans-gigantetrocinone, murisolin, isoannonacin, annonacin and goniothalamicin, muricatetrocins A and B, gigantetrocins A and B, goniothalamin, β-sitosterol and daucosterol.The antitumor test in vitro against human tumor cell lines indicated that most of the acetogenins from G. donnaiensis were active at different levels and showed some selectivity on certain human tumor cell lines, and thus were responsible for the bioactivity of the plant.
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