IDENTIFICATION OF MALE-SPECIFIC CHIRAL COMPOUND FROM THE SUGARCANE WEEVIL Sphenophorus levis

Abstract—Comparative gas chromatographic analyses of airborne volatiles produced by males and females of the sugarcane weevil Sphenophorus levis, showed one male-specific compound. Gas chromatography–mass spectrometry data indicated an aliphatic alcohol that was identified as 2-methyl-4-octanol. Both optical isomers were synthesized in five steps by employing commercially available (R)- and (S)-2,2-dimethyl-1,3-dioxolane-4-methanol as starting ma-terial. Enantiomeric resolution by gas chromatography with a chiral column demonstrated that the natural alcohol possessed the S configuration. Prelimi-nary indoor observations suggested that the alcohol elicited aggregation behav-ior among adults. The same compound has been previously described as an aggregation pheromone in several other curculionid species. Key Words—Sugarcane weevil, Sphenophorus levis, aggregation pheromone, 2-methyl-4-octanol, 3-methyl-4-octanol, Metamasius hemipterus