Antifungal Activity of Alkaloids from the Seeds of <i>Chimonanthus praecox</i>

<jats:title>Abstract</jats:title><jats:p><jats:boxed-text content-type="graphic" position="anchor"><jats:graphic xmlns:xlink="http://www.w3.org/1999/xlink" mimetype="image/gif" position="anchor" specific-use="enlarged-web-image" xlink:href="graphic/mcontent.gif"><jats:alt-text>magnified image</jats:alt-text></jats:graphic></jats:boxed-text></jats:p><jats:p>Two alkaloids, <jats:sc>D</jats:sc>‐calycanthine (<jats:bold>1</jats:bold>) and <jats:sc>L</jats:sc>‐folicanthine (<jats:bold>2</jats:bold>), were isolated from the active MeOH extract of the seeds of <jats:italic>Chimonanthus praecox</jats:italic> <jats:sc>Link</jats:sc>. The structures of the two compounds were established by <jats:sup>1</jats:sup>H‐ and <jats:sup>13</jats:sup>C‐NMR, and MS (FAB, ESI) analyses. In the <jats:italic>in vitro</jats:italic> tests, compounds <jats:bold>1</jats:bold> and <jats:bold>2</jats:bold> showed significant inhibitory activities against five plant pathogenic fungi <jats:italic>Exserohilum turcicum, Bipolaris maydis, Alternaria solani, Sclerotinia sderotiorum</jats:italic>, and <jats:italic>Fusarium oxysportium</jats:italic>, among which <jats:italic>B. maydis</jats:italic> was found to be the most susceptible to <jats:bold>1</jats:bold> with an <jats:italic>EC</jats:italic><jats:sub>50</jats:sub> value of 29.3 μg/ml, followed by <jats:italic>S. sderotiorum</jats:italic> to <jats:bold>2</jats:bold> with an <jats:italic>EC</jats:italic><jats:sub>50</jats:sub> value of 61.2 μg/ml. To our knowledge, this is the first report of isolation and LC/MS/MS identification as well as of antifungal properties of these alkaloids from the seeds of this plant.</jats:p>