A Chlorine-Atom-Controlled Terminal-Epoxide-Initiated Bicyclization Cascade Enables a Synthesis of the Potent Cytotoxins Haterumaimides J and K.

ABSTRACT: Haterumaimide J (hatJ) is reportedly the most cytotoxic member of the lissoclimide family of labdane diterpenoids. The unusual functional group arrangement of hatJ-C18 oxygenation and C2 chlorination-resisted our efforts at synthesis until we adopted an approach based on rarely studied terminal epoxide-based cation-π bicyclizations that is described herein. Using the C2-chlorine atom as a key stereocontrol element and a furan as a nucleophilic terminator, the key structural features of hatJ were rapidly constructed. The 18-step stereoselective synthesis features applications of chiral pool starting materials, and catalyst-, substrate-, and auxiliary-based stereocontrol. Access to hatJ and its acetylated congener hatK permitted their biological evaluation against aggressive human cancer cel

SUBMITTER: Michalak SE 

PROVIDER: S-EPMC6613971 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature