Three new xanthones from <i>Swertia bimaculata</i> and their anti-5<i>α</i>-reductase activity

<p>Three new xanthones (<b>1</b>–<b>3</b>), together with five known ones (<b>4</b>–<b>8</b>), were isolated from whole herb of <i>Swertia bimaculata</i>. Their structures were established on the basis of detailed spectroscopic analysis (1D- and 2D-NMR, HRESIMS, UV, and IR) and comparison with data reported in the literature. New isolates were evaluated for their anti-5<i>α</i>-reductase activity. The results revealed that all new compounds showed weak activity with reductase inhibitions of 40.5 ± 2.8, 38.6 ± 2.5, and 48.9 ± 3.0%, respectively.</p>