Laurencia glandulifera Laurene

The ability of marine organisms to synthesize halogenated sesquiterpenoids cf. ref. 105 and pp. 66, 79, 101) is further illustrated by the isolation of the laurane-type compounds (77)-(79) from red seaweed (Laurencia glandulifera). The absolute configuration of aplysinol (80), a metabolite of various species of Lauren-... 

The final step in an attempted synthesis of laurene, a hydrocarbon isolated from the marine alga Laurencia glandulifera, involved the Wittig reaction shown. The product obtained, however, was not laurene but an isomer. Propose a mechanism to account for these unexpected results. 

Laurene. Sesquiterpene from the red alga Laurencia glandulifera. L. co-occurs with many oxidized metabolites which have characteristic odors. 

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