Studies toward the total synthesis of dihydrolycolucine. Preparation of AB and CEF ring fragments

J Org Chem. 2014 Jun 20;79(12):5740-5. doi: 10.1021/jo500878v. Epub 2014 May 29.

Abstract

A strategy for the synthesis of the lycopodium alkaloid dihydrolycolucine (1) has been investigated. Synthetic routes were developed based on N-acylpyridinium salt chemistry to prepare target fragments 3 and 4 that could ultimately converge to the natural product. Key reactions include IMDA cycloadditions and retro-Mannich ring-openings to form both the AB and the EF ring fragments. The ring C precursor was prepared using pyridine substitution and directed lithiation chemistry. A Suzuki cross-coupling of rings C and EF led to the CEF ring fragment. Initial attempts at closure of the seven-membered D ring were unsuccessful.

Publication types

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

MeSH terms

  • Alkaloids / chemical synthesis*
  • Alkaloids / chemistry
  • Lycopodium / chemistry*
  • Molecular Structure
  • Pyridinium Compounds / chemistry
  • Quinolines / chemical synthesis*
  • Quinolines / chemistry
  • Stereoisomerism

Substances

  • Alkaloids
  • Pyridinium Compounds
  • Quinolines
  • dihydrolycolucine