Enantioselective syntheses of monotetrahydrofuran Annonaceous acetogenins tonkinecin and annonacin starting from carbohydrates

J Org Chem. 2001 Feb 9;66(3):853-61. doi: 10.1021/jo005643b.

Abstract

The total synthesis of two mono-THF acetogenins, tonkinecin (1) and annonacin (2), is reported in full detail. Terminal acetylene 3 prepared from D-glucono-delta-lactone and asymmetric dihydroxylation was employed as a common intermediate for both targets 1 and 2. Pd(0)-catalyzed coupling reaction of 3 with vinyl iodides 4 and 5, the chiral centers of which were taken from D-xylose and S-(-)-ethyl lactate, afforded enyne 26 and 27, respectively. Selective hydrogenation of 26 or 27 with diimide followed by removal of MOM ethers completed the synthesis of 1. A coupling reaction between the lithium derivative of 3 and epoxide 6 in the presence of boron trifluoride etherate gave 42. Both chiral centers in epoxide 6 were taken from L-ascorbic acid. Subsequent catalytic hydrogenation and MOM protection led to 43b. Introduction of the butenolide moiety by aldol condensation of protected S-lactal followed by cleavage of all MOM ethers completed the synthesis of 2.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Carbohydrates / chemistry*
  • Furans / chemical synthesis*
  • Furans / chemistry
  • Lactones / chemical synthesis*
  • Lactones / chemistry
  • Magnetic Resonance Spectroscopy
  • Magnoliopsida / chemistry*
  • Mass Spectrometry / methods
  • Stereoisomerism

Substances

  • Carbohydrates
  • Furans
  • Lactones
  • tonkinecin
  • annonacin