Pheromone biosynthetic pathways: Conversion of ipsdienone to (-)-ipsdienol, a mechanism for enantioselective reduction in the male bark beetle,Ips paraconfusus.

The enantiomeric composition of the pheromone components (+)-ipsdienoI, e.e. 87.6%, and (-)-ipsenol, e.e. 93.8%, produced by the male bark beetleIps paraconfusus (Scolytidae) under natural conditions was determined by HPLC separation of their diastereomeric ester derivatives. Males confined in an atmosphere of ipsdienone produced (-)-ipsdienol, e.e. 28%, and (-)-ipsenol, e.e. 86%, indicating an enantiomeric selectivity in the conversion of the ketone to the alcohols. These findings demonstrate an enantioselective conversion mechanism in the biosynthetic pathway to the pheromones from myrcene, a host-plant terpene.