The constitution of (1R)-sequirin-D (Sequoia sempervirens), a biogenetically novel norlignan, by direct X-ray analysis

Abstract

Sequoia sempervirens heartwood is shown to contain a new metabolite, sequirin-D[(1R)-1-(p-hydroxybenzyl)-6-hydroxy-1,2-dihydronaphthalene], whose constitution was determined by X-ray analysis (direct methods) of its di-O-methyl ether (4; R = Me); the structure was refined to R 6.4%. The chirality and biosynthesis of this norlignan, with a carbon skeleton new in nature, are discussed.