| Abstract
| - A convenient and high yielding method for thesynthesis of R-(−)-imperanene, starting from the readilyavailable natural lignan hydroxymatairesinol from Norwayspruce, was developed. Hydroxymatairesinol was degradedin strongly basic aqueous conditions to (E)-4-(4-hydroxy-3-methoxyphenyl)-2-(4-hydroxy-3-methoxyphenylmethyl)but-3-enoic acid, which was esterified and then reduced byLiAlH4 to afford R-(−)-imperanene. The configuration at thecrucial stereocenter was preserved in the synthesis, and theobtained product was identified by optical rotation measurements and chiral HPLC analyses as the R-(−)-enantiomer(ee 86−92%).
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