An enantioselective synthetic strategy toward the polyhydroxylated agarofuran

This paper describes a new approach for the enantioselective syntheses of n aturally occurring polyhydroxylated dihydroagarofuran sesquiterpenoids star ting from (-)-carvone. Through utilizing asymmetric Robinson annulation and acetoxylation as key steps, the agarofuran skeleton was enantioselectively constructed and an oxyfunctionalized group was introduced into the C-l pos ition. The important intermediate 23 to dihydroagarofuran was obtained in e leven steps. (C) 2001 Elsevier Science Ltd. All rights reserved.