Polygodial, insect antifeedant

Polygodial Warburgia stuhlmanii (Canellaceae), Insect antifeedant [pepper... 

The potent biological activity (insect antifeedant, antitumour, antifungal) of warburganal (35) has stimulated considerable synthetic interest in this compound. Three total syntheses of this compound have been recorded in the period under review. " The synthesis by Tanis and Nakanishi has additional flexibility since the key intermediate diol (34) can be used in the syntheses of cinnamolide (36), drimenin (37), and polygodial (38). Both norisoambreinolide (39 R = O) and isoambrox (39 R = H2) have been synthesized from (40), the product of the stannic chloride-catalysed cyclization of farnesyl phenyl sulphone. Yahazunol (41), a bicyclofarnesyl hydroquinone, has been identified in the brown seaweed... 

K. Mori and H. Watanabe, Synthesis of both the enantiomers of polygodial, an insect antifeedant sesquiterpene. Tetrahedron, 42 (1986) 273-281. 

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