Lymantria Disparlure

R,8S)-(+)-Disparlure (12) is the female sex pheromone of the gypsy moth (Lymantria dispar). Advent of Sharpless asymmetric dihydroxylation (AD) allowed several new syntheses of 12 possible. Sharpless synthesized 12 as shown in Scheme 17 [27]. Scheme 18 summarizes Ko s synthesis of 12 employing AD-mix-a [28]. He extended the carbon chain of A by Payne rearrangement followed by alkylation of an alkynide anion with the resulting epoxide to give B. Keinan developed another AD-based synthesis of 12 as shown in Scheme 19 [29]. Mit-sunobu inversion of A to give B was the key step, and the diol C could be purified by recrystallization. 

Some lepidopteran species secret methyl-branched chemicals for their sexual communication. These have been abbreviated with Me to indicate the position of the methyl group. Disparlure (Me2,epo7-18 H) is a well-known pheromone identified from Lymantria dispar [3] and two other species in the same genus, L.fumida [95] and L. monacha [96]. L. monacha also secrets an... 

Forest Lymantria dispar (gypsy moth) Me2,epo7-18 H (disparlure) USA 10,000 150,000... 

A study using the gypsy moth, Lymantria dispar, illustrates the overall pathways involved in production of epoxide pheromone components (Fig. 3) [77]. This insect uses disparlure, Me2,epo7-18 H, as a pheromone component. In-... 

L. monacha is sympatric with five other congeners, including Lymantria fumida, which has (7 .85)-cA-7,8-epoxy-2-methyloctadecane (called (+)-disparlure ) as... 

Figure 3.7 Production of the sex pheromone in the gypsy moth, Lymantria dispar. The oenocyte cells located in the abdomen biosynthesize the alkene hydrocarbon precursor to the pheromone, 2me-Z7-18 Hc. It is transported through the hemolymph by lipophorin. The alkene is taken up by pheromone gland cells where it is acted upon by an epoxidase to produce the pheromone disparlure, 2me-18 7,8Epox.

Dickens J. C., Oliver J. E. and Mastro V. C. (1997) Response and adaptation to analogs of disparlure by specialist antennal receptor neurons of gypsy moth, Lymantria dispar. J. Chem. Ecol. 23, 2197-2210. 

Jurenka, R. A., Subchev, M Abad, J.-L., Choi, M.-J. and Fabrias, G. (2003). Sex pheromone biosynthetic pathway for disparlure in the gypsy moth, Lymantria dispar. Proc. Natl. Acad. Sci. USA, 100, 809-814. 

Thus, the synthesis of the biologically active enantiomer of disparlure, the sex pheromone of the moth Lymantria dispar which causes severe damage to trees in some parts of the world, was achieved. This implied enantioselective... 

The Gypsy moth Lymantria dispar) is a dangerous forest pest (Fig. 8.82). Its caterpillars have reportedly defoliated and killed several hundred of tree and shrub species. They destroyed in the United States alone over 75 million acres of woodland since 1970. As noted above, of the sex attractant disparlure, only the (+)-enantiomer carries the bioactivity. 

Figure 3.23 Further examples of lepidopteran sex pheromones. These substances are all produced by adult females to attract males. In many cases the effective pheromone consists of a mixture of compounds, often isomers or homologues. Disparlure, the pheromone of the gypsy moth Lymantria dispar has a branched chain which starts with an isobutyric acid unit and is extended with acetic acid units. The three C2, unsaturated ketones are the pheromone of the Douglas-fir tussock moth Orgya pseudotsuga...

Several syntheses of natural products have been achieved with EHs as the key steps to introduce chirality. One of the first was the synthesis of the biologically active enantiomer of disparlure, the sex pheromone of the moth Lymantria dispar, which causes severe damage to trees in some parts of the world [159]. The synthesis was based on the kinetic resolution, mediated by a Pseudomonas strain, of rac-9,10-epoxy-15-methyl hexadecanoic acid, a precursor of the pheromone. The residual epoxide was then chemically converted in a Kolbe reaction into (+)-disparlure in 95% ee (Figure 8.41). 

Boness 568) used disparlure in field trials against the nun moth, Lymantria monacha, which is closely related to the gypsy moth. After treating 5 hectares of pine forest with 5.4 g of microencapsulated disparlure, he distributed 40 small disparlure-baited traps in the central part of the plot. Catches were reduced by 99% in comparison with a control plot. 

Racemic disparlure (536), the sex pheromone of the gypsy moth (Lymantria dispar), has been prepared by Klunenberg and Schafer 649) and Tolstikov et al. 650), and its geometric isomer (545) by Okada et al. 651). 

Boness, M. Disparlure Comparison of effectiveness in Lymantria dispar and Lyman-tria monacha as shown in field tests. VIII International Plant Protection Congress, Section V, Biological and Genetic Control, 41—47 (1975). 

Epoxides are not only key intermediates in several biosyntiieses they are also present in a number of secondary metabolites (Fig. 5). Again, the high reactivity of the epoxy moiety contributes to the bioactivity of these metabolites. This reactivity ensures short half-lives of metabolites, e.g., in juvenile hormones, pheromones, or the toxicity of some antibiotics. The methyl ester of 10,11-epoxyfamesenate 18 is a juvenile hormone synthesized by many insects. The pheromone disparlure 19 (see also Chapter 3 in this book) formed by the gypsy moth Lymantria dispar is active in only one enantiomeric form [8],... 

A crude enzyme preparation from the antennae of 1-day-old male gypsy moth (Lymantria dispar) was found to catalyze the enantioconvergent hydrolysis of ( )-disparlure 3.25 to the corresponding (7/ ,5J )-diol. However, for a single experiment, the antennae of 50 gypsy moths were required to provide just enough enzyme for the reaction, even at prolonged incubation times. It is obvious that this excludes these enzymes from practical applications. 

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