The Use of Acyclic Monoterpenes in the Preparation of β-pyrones; Synthesis of the Right-hand Fragment of Usneoidone E

Article abstract of DOI:10.1016/0040-4020(95)00084-L

The right hand fragment, 36, of Usneoidone E, 1, a powerful antiviral and antitumoural agent has been synthesized from the β-pyrone 32.Using lanalool as starting material, a 2,2,6,6-tetrasubstituted dihydropyrane 20, precursor of 32 and 33, was prepared. 20 was also synthesized from geranyl acetate through selenide 7, and is a versatile precursor for the synthesis of tetraprenyltoluquinols.Unambiguous 13C NMR assignment has been done by 2D correlations.