<jats:title>Abstract</jats:title><jats:p>From the methanolic extract of the roots of <jats:italic>Acacia confusa</jats:italic> Merr. (Leguminosae), (‐)‐2,3‐<jats:italic>cis</jats:italic>‐3,4‐<jats:italic>cis</jats:italic>‐4′‐methoxy‐3,3′,4,7,8‐pentahydroxyflavan (<jats:bold>1</jats:bold>), (‐)‐2,3‐<jats:italic>cis</jats:italic>‐3,4‐<jats:italic>cis</jats:italic>‐3,3′,4,4′,7,8‐hexahydroxyflavan (<jats:bold>2</jats:bold>), (‐)‐2,3‐<jats:italic>trans</jats:italic>‐3′,4′,7,8‐tetrahydroxydihydroflavonol (<jats:bold>3</jats:bold>), (+)‐catechin (<jats:bold>4</jats:bold>), (‐)‐epicatechin (<jats:bold>5</jats:bold>), 3′,4′,7,8‐tetrahydroxyflavonol (<jats:bold>6</jats:bold>) together with <jats:italic>N</jats:italic>‐methyltryptamine (<jats:bold>7</jats:bold>) and <jats:italic>N,N</jats:italic>‐dimethyltryptamine (<jats:bold>8</jats:bold>) were isolated, and their structures were established by analysis of their spectroscopic data. Among them, compound <jats:bold>1</jats:bold> was a new flavonoid. Additionally, the results of chromatographic bioassay on lettuce seeds indicated that compounds <jats:bold>7</jats:bold> and <jats:bold>8</jats:bold> exhibited significant phytotoxicity at a concentration lower than 14 mM.