Bioactive Constituents of Conyza Albida.

PACCIARONI, A.,; MONGELLI, E; ARIZA ESPINAR, L.,; ROMA NO, A.,; CICCIA, G.; SILVA, G

PLANTA MEDICA

Editor: Thieme. New York.

Lugar: New York; Año: 2000 vol. 66 p. 720 - 720

0032-0943

dir> The bioactivity-guided fractionation of an active chloroform extract of Conyza albida led to the isolation of three alkenynes, deca-4,6-diyn-2-(Z)-enoic methyl ester (1), deca-4,6-diyn-2-(Z)-enoic ethyl ester (2) and deca-2,4-dien-4-hydroxy-6-yn-1,4-olide (3), and the terpenoid spathulenol (4), as the active toxic metabolites in the Artemia sp. lethality test. When tested in the KB cell cytotoxicity assay, compounds 1-4 demonstrated IC50 values of 52.2, 38.4, 117.9, and 83.8 m M, respectively. All compounds studied were inactive in the DNA methyl green and DNA strand scission assays, while compounds 3 and 4 showed moderate activity as inhibitors of human topoisomerase I. Compound 2 is reported here for the first time.