From the ethanol extract of the whole plant of Ageratum conyzoides L. (Compositae), one new chromene, 2,2-dimethylchromene 7-methoxy-6-O-β-D-glucopyranoside, was isolated, together with thirteen known compounds, seven of which were being reported for the first time. The compounds were all characterized by MS, IR, 1D- and 2D-NMR spectroscopy. 7,3′,5′-tri-O-methyltricetin (7), precocene II (9),…