Synthesis and bioassay of the eight analogues of the CH503 male pheromone (3-acetoxy-11,19-octacosadien-1-ol) of the Drosophila melanogaster fruit fly.

Eight analogues of (3R,11Z,19Z)-CH503 (3-acetoxy-11,19-octacosadien-1-ol), the anti-aphrodisiac pheromone of male Drosophila melanogaster, were synthesized for a bioassay. These were the enantiomers of 3-acetoxy-11,19-octacosadiyn-1-ol (1), 3-acetoxyoctacosan-1-ol (2), (Z)-3-acetoxy-11-octacosen-1-ol (3), and (Z)-3-acetoxy-19-octacosen-1-ol (4). None of them were pheromonally active, indicating that the two double bonds at C-11 and C-19 were necessary for bioactivity.