Unconventional Fragment Usage Enables a Concise Total Synthesis of (-)-Callyspongiolide

J Am Chem Soc. 2018 Jan 31;140(4):1280-1284. doi: 10.1021/jacs.7b13591. Epub 2018 Jan 19.

Abstract

An asymmetric synthesis of (-)-callyspongiolide is described. The route builds the macrolide domain atypically from a disaccharide and a monoterpene without passing through a seco-acid. Chiral iridium catalysis selectively joins fragments. Subsequent degradation of an imbedded butyrolactone via perhemiketal fragmentation affords a stereo- and regio-defined homoallylic alcohol that is engaged directly in a carbonylative macrolactonization. Further elaboration of the polyunsaturated appendage provides the natural product in a particularly direct and flexible manner.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.