Dendroctonus

The western pine beetle Dendroctonus brevicomis is perhaps the most destmctive insect enemy of western pine forests. The aggregation pheromone is a mixture of the terpenoid myrcene [123-35-3J (163) from the tree and the frass pheromones exo-hsevicomki [20290-99-7] (164) and frontalin [28401-39-0] (165). The Norway spmce beede Ips tppopraphus converts the tree terpenoid myrcene into the frass pheromone ipsdienol [33628-00-3] (166) and the beedes also produce 2-methyl-3-buten-2-ol [115-18-4] and rir-verbenol [473-67-6] (167), all of which are components of the aggregation pheromone. 

Pimentel, D. Hokkanen, H. In Potential for Biological Control of Dendroctonus and Ips Bark Beetles Kulhavy, E. L. Miller, M. C., Eds. Center for Applied Studies, School of Forestry, Stephen F. Austin State University Nacogdoches, Texas, 1989. 

Evidence for de novo synthesis of pheromone components was obtained by showing that labeled acetate and mevalonate were incorporated into ipsdienol by male Ips pini [103,104]. Similarly, labeled acetate and other labeled intermediates were shown to be incorporated into frontalin in a number of Dendroctonus species [105]. Possible precursors to frontalin include 6-methyl-6-hep-ten-2-one, which was incorporated into frontalin by D. ruffipennis [106]. The precursor 6-methyl-6-hepten-2-one also was shown to be converted to bre-vicomin in the bark beetle, Dendroctonus ponderosae [107]. In addition, the expression patterns of HMG-CoA reductase and HMG-CoA synthase are tightly correlated with frontalin production in Dendroctonus jeffreyi [108, 109]. A geranyl diphosphate synthase cDNA from I. pini was also isolated, functionally expressed, and modeled [110]. These data indicate that the de novo isoprenoid biosynthetic pathway is present in bark beetles. A variety of other monoterpene alcohols such as myrcenol, pityol, and sulcitol are probably synthesized through similar pathways [111]... 

More recently, the deracemization of ( )-2c (Scheme 16) with Nocardia EHl and sulfuric acid in dioxane containing a trace amount of water (see above) afforded (S)-2-methyl-hept-6-ene-l,2-diol in 97% yield and 99% ee [83]. This intermediate was successfully applied in a short synthesis of (S)-(-)-frontalin, a central aggregation pheromone of pine beetles of the Dendroctonus family [81]. 

Wyatt, T. D., Phillips, D. G., and Gregoire, J.-C. (1993). Turbulence, trees and semiochemicals windtunnel orientation of the predator, Rhizophagus grandis, to its barkbeetle prey, Dendroctonus micans. PhysiologicalEntomology 18,204-210. 

Salom SM, Billings RE, Upton WW, Dalusky MJ, Grosman DM, Payne TI, Berisford GW, Shaver TN, Effect of verbenone enantiomers and racemic endo-brevicomin on response of Dendroctonus frontalis (Coleoptera Scolitidae) to attractant-baited traps, Can JForRes22 S2 i—3 i, 1992. 

Recently, M. Asami and T. Mukaiyama 124) synthesized ot-benzyloxyaldehydes (109) having a chiral tertiary center at the ot-carbon atom in high enantiomeric excess by successive treatment of the aminal (102) with diisobutylaluminium hydride (DIBAL-H) and Grignard reagents. The asymmetric reaction is applied to the total synthesis of exo-(+)-brevicomin (110), the principal aggregation pheromone in the frass of the female western pine beetle (Dendroctonus brevicomis). 

The cases where terpene metabolism has been studied In Insects are very few Indeed. Certain Ips and Dendroctonus bark beetles convert monoterpenes such as a-plnene, 6-plnene and myr-cene to oxidation products, some of which have pheromonal activities ( 5, 3A, 35). A Dendroc tonus bark beetle s cytochrome... 

R=OH). With less polar chloride substituents, however, the RhuA dia-stereoselectivity is reduced and a considerable fraction of the FucA configurated product (40%) is also formed. Interestingly, alkaline cyclization in the latter occurs with an inverse preference to furnish 177, which contains the enantiomeric bicyclic [3.2.1] structure shared by the FruA product 175 as well as by (S)-( — )-frontalin 178, the aggregation pheromone of the southern pine beetle Dendroctonus frontalis. 

Is of serious concern. The role of chemical communication, in relation to proposed control tactics, of predators and bark beetles will be discussed. Emphasis will be on Thanaslmus dublus (F.) (Coleoptera Clerldae) and Medetera blstrlata Parent (Dlptera Dollchopodldae) which are primary predators of the southern pine beetle, Dendroctonus frontalis Zimmermann (Coleoptera Scolytidae). 

Dendroctonus jejfreyi upregulate key mevalonate pathway enzymes during the induction of pheromone biosynthesis. 

Hall G. M., Tittiger C., Blomquist G. J., Andrews G., Mastick G., Barkawi L. A., Bengoa C. S. and Seybold S. J. (2002b) Male Jeffrey Pine Beetles, Dendroctonus jeffreyi, synthesize the pheromone component frontalin in anterior midgut tissue. Insect Biochem. Mol. Biol. 32, 1525-1532. 

Hughes P. R. and Renwick J. A. A. (1977a) Hormonal and host factors stimulating pheromone synthesis in female western pine beetles, Dendroctonus brevicomis. Physiol. Entomol. 2, 289-292. 

Nardi J. B., Gilg Young A., Ujhelyi E., Tittiger C., Lehane M. J. and Blomquist G. J. (2002) Specialization of midgut cells for synthesis of male isoprenoid pheromone in two scolytid beetles, Dendroctonus jeffreyi and Ips pini. Tissue and Cell. 226, 221— 231. 

Diaz E., Cisneros R. and Zuniga G. (2000) Comparative anatomical and histological study of the alimentary canal of the Dendroctonus frontalis (Coleoptera Scolytidae) complex. Ann. Entomol. Soc. Am. 93, 303-311. 

Specialization of midgut cells for synthesis of male isoprenoid pheromone components in two scolytid beetles, Dendroctonus jeffreyi and Ips pini. Tissue Cell. (in press). 

Zethner-M0ller O. and Rudinsky J. A. (1967) Studies on the site of sex pheromone production in Dendroctonus pseudotsugae (Coleoptera Scolytidae). Ann. Entomol. Soc. Am. 60, 575-582. 

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