A new minor homoisoflavonoid from <i>Caesalpinia sappan</i>

<div><p>Homoisoflavonoid is a special type of flavonoid with the perspectives of both chemical diversity and significant biological activities. During our ongoing studies on the discovery of novel homoisoflavonoids from traditional Chinese medicines, a new minor 3,4-di-<i>O</i>-substituted homoisoflavonoid, 3′,4-di-<i>O</i>-methylepisappanol (<b>1</b>), was isolated from <i>Caesalpinia sappan</i>, and its structure was determined to be (3<i>R</i>,4<i>R</i>)-3,7-dihydroxy-3-(3′-methoxy-4′-hydroxybenzyl)-4-methoxychroman by various spectroscopic analyses. Meanwhile, a known xanthone derivate, 2-methoxy-3-hydroxyxanthone (<b>2</b>) was also isolated, which is the first example from the genus <i>Caesalpinia</i>.</p>