Traceless synthesis of diketopiperazine fused tetrahydro-β-carbolines on soluble polymer support

Mol Divers. 2011 May;15(2):569-81. doi: 10.1007/s11030-010-9284-z. Epub 2010 Oct 10.

Abstract

The Pictet-Spengler reaction, using polyethylene glycol immobilized tryptophan ester with a variety of ketones, was achieved by refluxing condition in acidic chloroform. The linear as well as cyclic ketones were employed. All the ketones were reacted within 6-8 h to furnish soluble polymer-supported tetrahydro-β-carboline in good yields. Further expansion at N-terminus of tetrahydro-β-carbolines was achieved through a reaction with chloroacetyl chloride. Finally, the 2,5-diketopiperazine skeleton was constructed over a β-carboline by amination of the resulting N-chloroacetamides and subsequent intramolecular cyclization leading to cleavage of the polymer; constitutes a traceless synthesis of tetracyclic molecular architecture. Significantly, this strategy affords a straightforward and efficient approach for the construction of biological promising molecules with high purity and good yields.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amines / chemistry
  • Carbolines / chemical synthesis*
  • Carbolines / chemistry
  • Combinatorial Chemistry Techniques*
  • Diketopiperazines / chemistry*
  • Ketones / chemistry
  • Models, Chemical
  • Polymers / chemistry*
  • Solubility

Substances

  • Amines
  • Carbolines
  • Diketopiperazines
  • Ketones
  • Polymers
  • tryptoline