RT journal article
T1 Phytotoxins from Tithonia diversifolia
A1 M.Miranda, Maria A. F.
A1 J. Gualtieri, Sonia C.
A1 Varela Montoya, Rosa María
A1 Torres Martínez, Ascensión
A1 González Molinillo, José María
A1 Macías Domínguez, Francisco Antonio
A2 Química Orgánica
K1 Phytotoxins
K1 tithonia diversifolia
K1 Phytotoxic activity
K1 sesquiterpene lactones
AB Tithonia diversifolia (Mexican sunflower) is a dominant plant of the Asteraceae family, which suggests it produces allelochemicals that interfere with the development of surrounding plants. The study described herein was conducted to identify the compounds that have phytotoxic activity in T. diversifolia extracts. Ethyl acetate extracts of the leaves, stems, and roots showed significant inhibition of wheat coleoptile growth, and the leaf extract had similar inhibitory effects to a commercial herbicide. Fourteen compounds, 12 of which were sesquiterpene lactones, have been isolated. Two sesquiterpene lactones are reported for the first time and were isolated as an inseparable mixture of 8β-O-(2-methylbutyroyl)- tirotundin (4) and 8β-O-(isovaleroyl)tirotundin (5). Their structures were determined by spectroscopic analysis, including NMR techniques and mass spectrometry. The sesquiterpene lactones 1β methoxydiversifolin (6), tagitinin A (7), and tagitinin C (8) were the major products identified. These compoundswere active on etiolated wheat coleoptiles, seed germination, and the growth of STS and weeds. The phytotoxic activity shown by these sesquiterpene lactones indicates that they are the compounds responsible for the activity exhibited by the initial extracts.
PB Journal of Natural Products
YR 2015
FD 2015-04
LK http://hdl.handle.net/10498/20317
UL http://hdl.handle.net/10498/20317
LA eng
DS Repositorio Institucional de la Universidad de Cádiz
RD 12-nov-2026