Toxins (Jan 2014)

Stereoselective Luche Reduction of Deoxynivalenol and Three of Its Acetylated Derivatives at C8

  • Philipp Fruhmann,
  • Christian Hametner,
  • Hannes Mikula,
  • Gerhard Adam,
  • Rudolf Krska,
  • Johannes Fröhlich

DOI
https://doi.org/10.3390/toxins6010325
Journal volume & issue
Vol. 6, no. 1
pp. 325 – 336

Abstract

Read online

The trichothecene mycotoxin deoxynivalenol (DON) is a well known and common contaminant in food and feed. Acetylated derivatives and other biosynthetic precursors can occur together with the main toxin. A key biosynthetic step towards DON involves an oxidation of the 8-OH group of 7,8-dihydroxycalonectrin. Since analytical standards for the intermediates are not available and these intermediates are therefore rarely studied, we aimed for a synthetic method to invert this reaction, making a series of calonectrin-derived precursors accessible. We did this by developing an efficient protocol for stereoselective Luche reduction at C8. This method was used to access 3,7,8,15-tetrahydroxyscirpene, 3-deacetyl-7,8-dihydroxycalonectrin, 15-deacetyl-7,8-dihydroxycalonectrin and 7,8-dihydroxycalonectrin, which were characterized using several NMR techniques. Beside the development of a method which could basically be used for all type B trichothecenes, we opened a synthetic route towards different acetylated calonectrins.

Keywords