Quassinoids. An Approach to the BCDE Rings of Bruceantin

Article abstract of DOI:10.1021/jo00221a019

Synthesis of a model 28 for the BCDE rings of bruceantin via a BC -> BCE -> BCED ring strategy is presented.The sequence includes Diels-Alder reaction of methyl 3,5-hexadienoate 9 and quinone 8 derived from o-vanillyl alcohol, selenocyclization of hydroxy diester 22, and lactone formation to give the BCDE system 25.Manipulation on 25 showed the viability of its functional groups for further development in the synthetic strategy.