Laurencia 8-bromo-chamigren

Full details of an earlier synthesis of chamigrene (161) have been published.95 Further work on the components of the red alga Laurencia nipponica Yamada has resulted in the isolation and structural elucidation (by Y-ray analysis) of the diol (162)96 and spironippol (164).97 The biogenesis of the latter compound can be viewed in terms of an intramolecular cyclization of the diol (163) derivable from the naturally occurring epoxide of 10-bromo-a-chamigrene. 

Wolinsky, L.E. and Eaulkner, D.J. (1976) A biomimetic approach to the synthesis of Laurencia metabolites. Synthesis of 10-bromo-a-chamigrene. y. Org. Chem., 41, 597-600. 

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