title: Characterization of geometrid sex pheromones by electrospray ionization time-of-flight mass spectrometry.
abstract: The utility of liquid chromatography combined with time-of-flight mass spectrometry (LC/TOFMS) was demonstrated for studies on chiral unsaturated epoxy compounds, sex pheromones produced mainly by female moths in the family Geometridae. By electrospray ionization (ESI), each synthetic epoxyalkadiene derived from (Z,Z,Z)-3,6,9-triene with a C(18)-C(23) straight chain showed three ion series, [M + NH(4)](+), [M + H](+) and [M - OH](+), with high resolution and good sensitivity, indicating its molecular formula. In addition to these, characteristic fragment ions at m/z M - 57 and M - 71 for the 3,4-epoxides and at m/z M - 123 and 123 for the 9,10-epoxides were detected, whereas the 6,7-epoxides did not produce fragment ions that reflected their structures. Monitoring these diagnostic ions during the LC/MS analysis of a gland extract, the natural sex pheromone of the mulberry looper was confirmed to be (Z,Z)-cis-9,10-epoxy-3,6-octadecadiene, which was separable from the other positional isomers on an ODS column. Furthermore, (Z,Z)-cis-3,4-epoxy-6,9-nonadecadiene secreted by the Japanese giant looper was analyzed with a chiral column, and the stereochemistry was determined directly.
authors.affiliation: Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Yamazawa
authors.forename: Masanobu
authors.initials: M
authors.lastname: Yamamoto
authors.forename: Kaoru Iida
authors.initials: KI
authors.lastname: Karasawa
authors.forename: Guan-Qin
authors.initials: GQ
authors.lastname: Pu
authors.forename: Tetsu
authors.initials: T
authors.lastname: Ando
mesh_terms: D000818:Animals; D002853:Chromatography, Liquid; D004852:Epoxy Compounds / Q000138:chemical synthesis / Q000737:chemistry; D007915:Lepidoptera / Q000737:chemistry*; D012724:Sex Attractants / Q000138:chemical synthesis / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D004852:Epoxy Compounds; D012724:Sex Attractants