Synthesis and characterization of diepoxyalkenes derived from (3Z,6Z,9Z)-trienes: Lymantriid sex pheromones and their candidates

All stereoisomers of three diepoxyalkenes derived from (3Z,6Z,9Z)-trienes w ith a C-21, C-19, or C-18 straight chain, lymantriid sex pheromones and the ir candidates, were synthesized by MCPBA oxidation of optically active epox yalkadienes. Their chromatographic behaviors were examined with GC and LC e quipped with achiral and chiral columns. Detailed inspection of the mass sp ectra of these epoxides indicated the following diagnostic ions for determi ning the chemical structures: m/z 128, 167, M-87 and M-85 for (Z)-cis-3,4-c is-6,7-diepoxy-9-enes; m/z 111, M-125 and M-69 for (Z)-cis-6,7-cis-9,10-die poxy3-enes; and m/z M-125 and M-139 for (Z)-cis-3,4-cis-9,10-diepoxy-6-enes . Mass chromatographic analysis that monitored these fragment ions revealed the existence of a new pheromonal compound with a C-21 chain in an extract from virgin females of a lymantriid species, Perina nuda F. The three diep oxyalkenes were converted into the corresponding DMDS adducts, which showed characteristic ions from fragmentation between the two thiomethyl groups, reflecting the position of an original double bond.