Phenylnaphthalene pigments of Lachnanthes tinctoria. II. Synthesis of two phenylnaphthalides

Abstract

The structures previously assigned to two of the fully methylated lactones derived from Lachnanthes tinctoria constituents have now been confirmed by synthesis. Nuclear magnetic resonance spectra have been used for a study of the stereochemistry of highly substituted phenyltetralins obtained as intermediates in the syntheses.