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Lignans are an important series of natural products. 1, 2 A variety of lignan classes have been isolated from different plants, and the syntheses of these different lignan structural types have been published. 3-10 Lignans are usually classified into three classes based on the character of the CC bond and oxygen bridge joining the two typical phenylpropane units that make up their general structure. The acyclic lignan derivatives constitute the first of these classes as illustrated by structure 1 (Figure 1). This class includes dibenzylbutanes, dibenzyl substituted tetrahydrofurans, dibenzylbutyrolactones, diphenyltetrahydrofuran [3, 4-C] furofurans, and others. 11-23 A second class of lignans contains arylnaphthalene derivatives (see structure 2), such as podophyllotoxin, which feature a C-6 and C-7′ connection between the two phenylpropane units. 24-44 Dibenzocyclooctadiene derivatives with a C-6, C-6′ biaryl bond …