A concise synthesis of berkelic acid inspired by combining the natural products spicifernin and pulvilloric acid.

ABSTRACT: We describe a concise synthesis of the structurally novel fungal extremophile metabolite berkelic acid, an effort leading to an unambiguous assignment of C22 stereochemistry. Our synthetic approach was inspired by the recognition that berkelic acid displays structural characteristics reminiscent of two other fungal metabolites, spicifernin and pulvilloric acid. Based on this notion, we executed a synthesis that features a Ag-catalyzed cascade dearomatization-cycloisomerization-cycloaddition sequence to couple two natural product inspired fragments. Notably, a spicifernin-like synthon was prepared with defined C22 stereochemistry in seven steps and three purifications (24-28% overall yield). A potentially useful anti-selective conjugate propargylation reaction was developed to introduce the

SUBMITTER: Bender CF 

PROVIDER: S-EPMC2769089 | biostudies-literature | 2009 Aug

REPOSITORIES: biostudies-literature