Progress on the chemistry of dibenzocyclooctadiene lignans

Synthetic methodologies for dibenzocyclooctadiene lignans is divided into intermolecular and intramolecular biaryl couplings. The former requires multiple linear steps which generate the lignans in low overall yields. In contrast, biomimetic inspired intramolecular approach, in which two or more relatively advanced fragments are used to make a fully functionalized intermediate, realizes a reduction in synthetic steps and an increase in overall yields. In addition, spectral characteristics of these lignans are analyzed by nuclear magnetic resonance (NMR), infrared (IR), ultraviolet (UV), mass spectrometry (MS), and circular dichroism (CD) spectroscopy. Alternative strategy for obtaining optically active dibenzocyclooctadiene lignans is by chromatographic separation of diastereomeric acyclic biphenyl derivatives.