Dehydrative cyclization catalyzed by the combination of molybdenum(VI) oxides and benzoic acids: First synthesis of the antitumour substance BE-70016

Akira Sakakura, Shuhei Umemura, Rei Kondo, Kazuaki Ishihara

Research output: Contribution to journalArticle

20 Citations (Scopus)


The dehydrative cyclization of N-(o-hydroxybenzoyl)threonine derivative la is efficiently promoted by the combined use of molybdenum(VI) oxides and benzoic acids bearing electron-with-drawing substituents. In the presence of ammonium molybdate [(NH4)2MoO4, 10 mol%] and penta-fluorobenzoic acid (C6F5CO2H; 10 mol%), dehydrative cyclization of la was conducted in toluene under azeotropic reflux conditions to give 2-(o-hydroxyphenyl)oxazoline 2a in 76% yield. Furthermore, the first total synthesis of the antitumour substance BE-70016 was achieved using the catalytic dehydrative cyclization of 1a as a key reaction.

Original languageEnglish
Pages (from-to)551-555
Number of pages5
JournalAdvanced Synthesis and Catalysis
Issue number4-5
Publication statusPublished - Mar 1 2007



  • Catalysis
  • Dehydrative cyclization
  • Molybdenum(VI) oxide
  • Oxazolines
  • Pentafluorobenzoic acid

ASJC Scopus subject areas

  • Catalysis
  • Organic Chemistry

Cite this