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Five new annonaceous acetogenins, calamistrins C-G (1-5), were isolated from an ethanolic extract of the roots of Uvaria calamistrata. Compounds 1-3 were mono-THF ring acetogenins; compounds 4 and 5 were bis-THF acetogenins, with the THF rings from C-18 to C-25. The absolute configurations of 3, 4, and 5 as well as the partial absolute configurations of 1 and 2 were determined by (13)C NMR spectroscopy and advanced Mosher methodology.

Two novel gamma-lactones, saccopetrin C(1) and saccopetrin D (2), were isolated from the roots of Saccopetalum prolificum. Their structures were established by spectroscopic and chemical methods.

Two new bioactive monotetrahydrofuran acetogenins, calamistrins A (1) and B (2), and two known compounds, uvarigrin (3) and uvarigranin (4), have been isolated from the roots of Uvaria calamistrata. The structures of the new compounds were elucidated by spectroscopic and chemical methods. The absolute stereochemistry of the stereogenic centers was established by Mosher ester methodology.

Three new styryl-lactones 8-acetylgoniofufurone(1), 7-acetylgonio-pypyrone(3), and 5-acetylgoniopypyrone(4), along with ten known compounds, goniofufurone(2), goniopypyrone(5), goniothalamin, goniothalenol, (+)-isoaltholactone, goniodiol, 7-acetylgoniodiol, goniotriol, 8-acetylgoniotriol, 9-deoxygoniopypyrone were isolated from the rhizomes of Goniothalamus griffithii Hook f. et. Thoms. Their structures were elucidated by IR, MS, NMR spectra and chemical evidence. All compounds showed cytotoxic activities against human cancer cell lines.

Two new acetogenins, gardnerilins A and B, have been isolated from the roots of Goniothalamus gardneri. Both are C35 acetogenins containing non-tetrahydrofuran rings. Their structures have been established on the basis of spectral evidence.

Two new cytotoxic annonaceous acetogenins, named uvarigrin(1) and uvarigrandin A(3), were obtained from the roots of Uvaria grandiflora Roxb(Annonaceae). Based on X-ray analysis and Mosher's methodology, the overall absolute configuration of 1 was established as 15S, 17R, 18R, 21R, 22R, 36S. The absolute configuration of 3 was also resolved by Mosher's methodology. The relative configuration of the previously reported uvarigranin (2) was revised. Compound 1 showed cytotoxicity against HCT-8, Bel7402 and A2780 human tumor cell lines at ED50 levels of 0.15, 0.21 and 0.41 microgram.ml-1, respectively.

Further studies on the root bark of Uvaria tonkinensis Finet et Gagnep. (Annonacease) led to the isolation of a new Annonaceous acetogenin, tonkinelin (1). The structure of 1 was elucidated on the basis of spectral data and chemical evidence. This compound represents an unusual type of C37 Annonaceous acetogenin, having neither tetrahydrofuran (THF) nor epoxide rings and possessing only a vicinal diol in the hydrocarbon chain. Preliminary pharmacological tests showed that tonkinelin (1) inhibits human leukemia (HL-60) and human colon adenocarcinoma (HCT-8) cell lines in vitro.

A novel bioactive monotetrahydrofuran acetogenin named tonkinecin (1) and two known compounds, uvariamicins I and II, have been isolated from the roots of Uvaria tonkinesis. The structure of 1 was elucidated using spectral methods and its absolute stereochemistry established by 1H-NMR experiments utilizing Mosher ester methodology.