Studies on Constituents of Medicinal Plants. VIII. The Stereochemistry of Paulownin and Isopaulownin

Abstract

The stereochemistry of paulownin, isopaulownin, m.p. 132°, which was derived from paulownin with 20% EtOH-HCl or 5% HCOOH, d-sesamin and d-asarinin were elucidated as IIa, IIb, Ia and Ib by the analysis of their NMR spectra, respectively and consequently, epi-asarinin as Ic.