Crystal structure and conformation of pakyonol, a macrocyclic bis(bibenzyl) constituent of Mannia fragrans

Abstract

An X-ray analysis of the crystal structure of the title compound has been carried out. For the bond length of one of the ethylene bridges an unreasonably low value was calculated probably due to disorder in the crystal. The disorder was revealed by means of molecular mechanics calculations, which also threw light on further details of the conformational behaviour of the ring system.