Characterization of geometrid sex pheromones by electrospray ionization time-of-flight mass spectrometry

✍ Scribed by Hiroyuki Yamazawa; Masanobu Yamamoto; Kaoru Iida Karasawa; Guan-Qin Pu; Tetsu Ando

• Publisher: John Wiley and Sons
• Year: 2003
• Tongue: English
• Weight: 141 KB
• Volume: 38
• Category: Article
• ISSN: 1076-5174
• DOI: 10.1002/jms.445

✦ Synopsis

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. Copyright © 2003 John Wiley & Sons, Ltd.