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Chemical and spectroscopic studies lead to the [7,0] metacyclophane structures (2) and (3) for myricanol and myricanone, phenolic extractives from Myrica nagi. X-Ray analysis of the meta-bridged biphenyl, 16-bromomyricanol (nitromethane solvate), by the heavy-atom method, confirmed these assignments, and gave the absolute configuration of myricanol. The compound crystallises in the monoclinic space group P2, with Z = 2 in a unit cell of dimensions a = 6.02 * 0.01. b = 17.34 f 0.02, c = 11 a 2 2 f 0.02 8, and p = 98.4" f 0.2"; the structure was refined to R 0.057 for 1075 independent reflections. C.d. measurements suggest t h a t myricanol prefers t h e same conformation in solution as in the crystalline state. The biphenyl nucleus in 16-bromomyricanot is detormed by metameta-bridging. Similar strain in myricanone (3) is relieved by rearrangement with Lewis acids to the onho,rneta-bridged ketone (1 3). The natural phenols may be biogenetically related to diarylheptanoids.THE stem bark of Mypica nagi (Myricaceae) (reputed to be a fish poison) has been stated 2 to contain the rotenoid (I) among its phenolic constituents, with a t r a n s -~/ c ring fusion of unspecified absolute configuration, and a previously all assigned a C ~S -B / C junction (6aSJ12aS) with ring E attachment, if present,, isoprenoid (or degraded isoprenoid) in character. We have attempted reisolation of the claimed rotenoid, without success. t r 11 10 hexadienyl substituent in ring E. Both reported The phenolic fractions from M . nagi have instead features would be unique among natural rote no id^,^ yielded two unusual meta-bridged biphenyls, myricanol, t Professor Seshadri has informed us that the rotenoid assigne v. K*shnamoodhy, N. R. Krisnaswamy, and T. R. seshadri, ment should now be withdrawn.

Lignans2.1 Dibenzylbutanes, Dibenzylbutyrolactones, and Substituted Furans This Section covers those lignans containing only one carboncarbon bond (8-8') between the two shikimate-derived biogenetic subunits.' meso-Nordihydroguaiaretic acid (1) was used for many years

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