New Phytotoxic Cassane-like Diterpenoids from Eragrostis plana

作者：Adriana Favaretto, Charles L. Cantrell, Frank R. Fronczek, Stephen O. Duke, David E. Wedge, Abbas Alı, Simone Meredith Scheffer-Basso · 发表于：Journal of Agricultural and Food Chemistry · 年份：2019 · DOI：10.1021/acs.jafc.8b06832 · 被引用次数：19 · 研究领域：Allelopathy and phytotoxic interactions、Weed Control and Herbicide Applications、Biological Control of Invasive Species

Eragrostis plana (Nees) is an allelopathic plant with invasive potential in South American pastures. To isolate and identify phytotoxic compounds from leaves and roots of E. plana, a bioassay-directed isolation of the bioactive constituents was performed. This is the first report on a new diterpene carbon skeleton, neocassane, and of three new neocassane diterpenes, neocassa-1,12(13),15-triene-3,14-dione, 1; 19-norneocassa-1,12(13),15-triene-3,14-dione, 2; and 14-hydroxyneocassa-1,12(17),15-triene-3-one, 3, identified from the roots. Compounds 1, 2, and 3 inhibited the growth of duckweed by 50% at concentrations of 109 ± 28, 200 ± 37, and 59 ± 15 μM, respectively. Compound 2 was fungicidal to Colletotrichum fragariae, Colletotrichum acutatum, and Colletotrichum gloeosporioides. The compounds identified here could explain the allelopathy of E. plana. The description of the newly discovered compounds, besides contributing to the chemical characterization of the species, may be the first step in the study of the potential of these compounds as bioherbicides.