Synthesis and bioassay of racemic and chiral trans-alpha-necrodyl isobutyrate, the sex pheromone of the grape mealybug Pseudococcus maritimus

J Agric Food Chem. 2010 Apr 28;58(8):4977-82. doi: 10.1021/jf904452v.

Abstract

A concise synthesis of the racemic form of the female-produced pheromone of the grape mealybug was developed. The synthesis was readily adapted to production of both enantiomers of the pheromone via lipase-catalyzed kinetic resolution of an intermediate in the synthesis. Replicated field trials revealed that, contrary to a preliminary report, the (R,R)- rather than the (S,S)-enantiomer is the attractive stereoisomer. Lithium aluminum hydride reduction of the insect-produced compound to alpha-necrodol followed by analysis on a chiral stationary phase GC column showed that the insect-produced material was actually an 85:15 mixture of the (R,R)- and (S,S)-enantiomers. The racemic form of the pheromone was highly attractive to male mealybugs, and in one of two field bioassays, the racemic material was significantly more attractive than the pure (R,R)-enantiomer, suggesting that the (S,S)-enantiomer might act synergistically.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Biological Assay*
  • Butyrates / chemical synthesis*
  • Butyrates / pharmacology*
  • Female
  • Insecta*
  • Kinetics
  • Magnetic Resonance Spectroscopy
  • Male
  • Sex Attractants*
  • Stereoisomerism

Substances

  • Butyrates
  • Sex Attractants
  • trans-alpha-necrodyl isobutyrate