Synthesis of a Bicyclic Azetidine with In Vivo Antimalarial Activity Enabled by Stereospecific, Directed C(sp3)-H Arylation

J Am Chem Soc. 2017 Aug 16;139(32):11300-11306. doi: 10.1021/jacs.7b06994. Epub 2017 Aug 7.

Abstract

The development of new antimalarial therapeutics is necessary to address the increasing resistance to current drugs. Bicyclic azetidines targeting Plasmodium falciparum phenylalanyl-tRNA synthetase comprise one promising new class of antimalarials, especially due to their activities against three stages of the parasite's life cycle, but a lengthy synthetic route to these compounds may affect the feasibility of delivering new therapeutic agents within the cost constraints of antimalarial drugs. Here, we report an efficient synthesis of antimalarial compound BRD3914 (EC50 = 15 nM) that hinges on a Pd-catalyzed, directed C(sp3)-H arylation of azetidines at the C3 position. This newly developed protocol exhibits a broad substrate scope and provides access to valuable, stereochemically defined building blocks. BRD3914 was evaluated in P. falciparum-infected mice, providing a cure after four oral doses.

Publication types

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

MeSH terms

  • Animals
  • Antimalarials / chemical synthesis*
  • Antimalarials / chemistry
  • Antimalarials / pharmacology
  • Antimalarials / therapeutic use*
  • Azetidines / chemical synthesis*
  • Azetidines / chemistry
  • Azetidines / pharmacology
  • Azetidines / therapeutic use*
  • Bridged Bicyclo Compounds / chemical synthesis
  • Bridged Bicyclo Compounds / chemistry
  • Bridged Bicyclo Compounds / pharmacology
  • Bridged Bicyclo Compounds / therapeutic use
  • Catalysis
  • Disease Models, Animal
  • Hep G2 Cells
  • Humans
  • Malaria, Falciparum / drug therapy*
  • Mice, Inbred NOD
  • Mice, SCID
  • Palladium / chemistry
  • Plasmodium falciparum / drug effects*
  • Stereoisomerism

Substances

  • Antimalarials
  • Azetidines
  • Bridged Bicyclo Compounds
  • Palladium