Venezenin: A New Bioactive Annonaceous Acetogenin from the Bark of Xylopia aromatica

Abstract

Asimicin and a new cytotoxic Annonaceous acetogenin, venezenin [1], were isolated from the bark of Xylopia aromatica by bioactivity-directed fractionation using lethality to brine shrimp. Compound 1 represents an unusual type of C37 Annonaceous acetogenin, lacking either tetrahydrofuran (THF) or epoxide rings and possessing a double bond located two methylenes away from a vicinal diol in the hydrocarbon chain. The structure of 1 was elucidated by 1H- and 13C-nmr, COSY, single-relayed COSY, and by HMBC techniques, and derivatization. Annomontacin 10-one [6] and 18/21-cis-annomontacin-10-one [7], two semi-synthetic mono-THF acetogenins were prepared from 1. These acetogenins showed cytotoxicity, comparable or superior to adriamycin, against three human solid tumor cell lines. Reduction of the 10-keto of 1 to the racemic OH-10 derivative enhanced the bioactivity, as did the conversion of 1 to 6 and 7. Venezenin [1], like other Annonaceous acetogenins, showed inhibition of oxygen uptake by rat liver mitochondria and demonstrated that the THF ring may not be essential to this mode of action.

Antiprotozoal and cytotoxic activities in vitro of Colombian Annonaceae

“…Alkaloids, amides, lignoids, acetogenines and terpenes (mono, di and sesquiterpenes) are the most important metabolites (Martins et al, 1999;Stashenko et al, 2004). Because stems are especially rich in acetogenines (Saizarbitoria et al, 1994(Saizarbitoria et al, , 1995Alfonso et al, 1996), this metabolite could be responsible for antiparasitic activity observed in this study.…”

Acetogenins from Annonaceae

“…The same comment can be made for goniothalamicin and its translactonized derivative goniothalamicinone. It is interesting that reference of a tetrahydrofuran ring is not essential, since venezenin shows promising activity (30).…”

Estudo fitoquímico de Unonopsis lindmanii - Annonaceae, biomonitorado pelo ensaio de toxicidade sobre a Artemia salina leach

“…Várias espécies da família Annonaceae foram estudadas empregando o bioensaio TAS, juntamente com outros ensaios biológicos [7][8][9][10] . Porém, nenhuma espécie do gênero Unonopsis havia sido quimicamente investigada utilizando monitoramento por bioensaio.…”