Access to oxetane-containing psico-nucleosides from 2-methyleneoxetanes: a role for neighboring group participation?

J Org Chem. 2011 Dec 16;76(24):9962-74. doi: 10.1021/jo201565h. Epub 2011 Nov 15.

Abstract

The first psico-oxetanocin analogue of the powerful antiviral natural product, oxetanocin A, has been readily synthesized from cis-2-butene-1,4-diol. Key 2-methyleneoxetane precursors were derived from β-lactones prepared by the carbonylation of epoxides. F(+)-mediated nucleobase incorporation provided the corresponding nucleosides in good yield but with low diastereoselectivity. Surprisingly, attempted exploitation of anchimeric assistance to increase the selectivity was not fruitful. A range of 2-methyleneoxetane and related 2-methylenetetrahydrofuran substrates was prepared to explore the basis for this. With one exception, these substrates also showed little stereoselectivity in nucleobase incorporation. Computational studies were undertaken to examine if neighboring group participation involving fused [4.2.0] or [4.3.0] intermediates is favorable.

Publication types

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

MeSH terms

  • Adenine / analogs & derivatives*
  • Adenine / chemical synthesis
  • Antiviral Agents / chemical synthesis*
  • Butylene Glycols / chemistry
  • Epoxy Compounds / chemistry*
  • Ethers, Cyclic / chemistry*
  • Fluorine / chemistry
  • Furans / chemical synthesis
  • Humans
  • Lactones / chemistry*
  • Magnetic Resonance Spectroscopy
  • Molecular Structure
  • Nucleosides / chemistry*
  • Stereoisomerism

Substances

  • 2-methyleneoxetane
  • Antiviral Agents
  • Butylene Glycols
  • Epoxy Compounds
  • Ethers, Cyclic
  • Furans
  • Lactones
  • Nucleosides
  • oxetanocin
  • penitricin C
  • Fluorine
  • Adenine