Stereoselective cascade double-annulations provide diversely ring-fused tetracyclic benzopyrones

Org Lett. 2012 Dec 7;14(23):5924-7. doi: 10.1021/ol3028412. Epub 2012 Nov 14.

Abstract

A cascade double-annulation strategy employing diverse pairs of zwitterions with 3-formylchromones is presented that provides stereoselective access to complex tetracyclic benzopyrones. Different zwitterions incorporated different rings that include aza-, oxa-, and carbocycles fused to a common benzopyrone scaffold and in the process created three contiguous chiral centers including an all-carbon-quaternary center with high efficiency and excellent stereoselectivity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cyclization
  • Heterocyclic Compounds, 4 or More Rings / chemical synthesis*
  • Heterocyclic Compounds, 4 or More Rings / chemistry
  • Molecular Structure
  • Pyrones / chemical synthesis*
  • Pyrones / chemistry
  • Stereoisomerism

Substances

  • Heterocyclic Compounds, 4 or More Rings
  • Pyrones