Efforts toward the Total Synthesis of Thuggacin A

Org Lett. 2024 Nov 29;26(47):10090-10095. doi: 10.1021/acs.orglett.4c03643. Epub 2024 Nov 15.

Abstract

Thuggacin A (1) is a 17-membered-ring-polyketide antibiotic compound with excellent antituberculosis activity. The total synthesis of thuggacin A has not yet been reported so far. Herein, we disclose our efforts toward the convergent total synthesis of thuggacin A. The key synthetic features include our own one-pot cascade thiazole formation, Evans syn-aldol, Mukaiyama asymmetric aldol reaction, organosilicon-promoted selective alkyne reduction, Shiina macrolactonization, and a nucleophilic ring-opening of epoxide with alkyne to assemble the main framework of thuggacin A. The enantioselective synthesis of trimethylsilyl ethoxymethyl (SEM) derived thuggacin A analogue 2 was achieved in 18 longest linear steps with 2.0% overall yield, and the bioassay of 2 exhibited moderate antituberculosis activity with minimum inhibitory concentration (MIC) of 320 μg/mL.

MeSH terms

  • Antitubercular Agents* / chemical synthesis
  • Antitubercular Agents* / chemistry
  • Antitubercular Agents* / pharmacology
  • Microbial Sensitivity Tests
  • Molecular Structure
  • Mycobacterium tuberculosis / drug effects
  • Stereoisomerism
  • Thiazoles / chemical synthesis
  • Thiazoles / chemistry
  • Thiazoles / pharmacology

Substances

  • Antitubercular Agents
  • Thiazoles