ISSN:
1573-1561
Keywords:
Chiral HPLC
;
sex pheromone
;
Lepidoptera
;
Geometridae
;
epoxydiene
;
stereochemistry
;
Mosher's method
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Chemistry and Pharmacology
Notes:
Abstract Resolution of insect pheromonal cis-epoxydiene racemates derived from (Z,Z,Z)-3,6,9-trienes with a C18–C23 chain was examined utilizing chiral HPLC columns, and the result showed that a Chiralpak AS column was suitable to separate enantiomers of the 3,4-epoxides, and a Chiralpak AD column was indispensable for the resolution of the racemic 6,7- and 9,10-epoxides. The absolute configuration of the enantiomers of the 3,4- and 9,10-epoxides separated by HPLC was studied after methanolysis of their epoxy rings. Examination of the 1H NMR data from esters of the methoxyalcohols produced by a modified Mosher's method with (S)- and (R)-α-methoxy-α-(trifluoromethyl)phenylacetic acid indicated that the dextrorotatory parent epoxides with a shorter R t were 3S,4R and 9S,10R isomers and the levorotatory enantiomers having a longer R t possessed 3R,4S and 9R,10S configuration. Field tests with both enantiomers of (Z,Z)-6,9-cis-3,4-epoxynonadecadiene separated by HPLC with the chiral column revealed new specific attraction of geometrid forest defoliators, Pachyerannis obliquaria, to the 3R,4S isomer and Zethenia albonotaria nesiotis to the 3S,4R isomer.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/B:JOEC.0000006472.12370.c6
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