Structure of pinnarin and furopinnarin, two new coumarins from the roots of Ruta pinnata

Abstract

Seven coumarins were isolated from the roots of Ruta pinnata L. fil. Five were identified as xanthyletin, luvangetin, isopimpinellin, sabandin and thamnosin; the remaining two are new compounds, furopinnarin (I) and pinnarin (III). The tetrahydro derivative (II) was obtained from I and the dihydro derivative (IV) as well as isopinnarin (V), cyclopinnarin (VI), and limettin (VII) were obtained from III. Possible structures for sabandin (IX, X or XI) are discussed.