Moth pheromones

This is the first example of a reaction for which the presence of a chelating ligand was observed to facilitate rather than retard metal-catalysed epoxidation (Gao et al., 1987). It was found that the use of molecular sieves greatly improves this process by removing minute amounts of water present in the reaction medium. Water was found to deactivate the catalyst. All these developments led to an improved catalytic version that allows a five-fold increased substrate concentration relative to the stoichiometric method. Sensitive water-soluble, optically active glycidols can be prepared in an efficient manner by an in situ derivatisation. This epoxidation method appears to be competitive with enzyme-catalysed processes and was applied in 1981 for the commercial production of the gypsy moth pheromone, (-1-) disparlure, used for insect control (Eqn. (25)). 

The substrate-controlled addition of 18 to 19 proceeded with good enantioselec-tivity and was used to prepare the epoxide (+)-dispalure, a gypsy moth pheromone.184... 

Show how organoborane intermediates can be used to synthesize the gypsy moth pheromone E, Z-CH3C02(CH2)4CH=CH(CH2)2CH=CH(CH2)3CH3 from hept-6-ynyl acetate, allyl bromide, and 1-hexyne. 

Commercial synthesis of the gypsy moth pheromone (7R,SS)-d sparlure by J. T. Baker ... 

Biologists have known of these intertwined lives for more than a century, but only more recently have they brought modern tools to bear on the relationship. Along with several other points, the role of chemical signals here is still unsettled. The moths may locate yucca flowers by scent, sight, or both. For such a scientifically well-known interaction, it would be interesting to know more. If yuccas do emit a chemical attractant, the scent apparently attracts only yucca moths, a selectivity suggesting an attractant that mimics some unsuspected moth pheromone. 

The structures of the female produced pheromones of the sugar cane wire worms Melanotus sakishimensis and M. okinawensis look much more like conventional moth pheromones While in the latter species it simply is dodecyl acetate, M. sakishimensis uses a mixture of ( 9,ll)-dodecadienyl butyrate 94 (Scheme 10) and the corresponding hexanoate [192]. 

Compounds 15-19 belong to the major class of moth pheromones that are biosynthesized by the action of a desaturase on a fatty acyl precursor followed by modification of the polar head group of the alkyl chain (Francke and Schulz,... 

This review considers evidence for selective forces that mold the chemical signal and behavioral response, including the characteristics of pheromone dispersal and the plume-tracking maneuvers that influence the success of mate finding. Recent reviews that consider mechanisms of evolutionary change in moth pheromones include Phelan (1992,1996,1997), Lofstedt (1993), Linn and Roelofs (1995), and Lofstedt and Kozlov (1996). 

Lofstedt, C. (1993). Moth pheromone genetics and evolution. Philosophical Transactions of the Royal Society London, Series 340 167-177. 

Lundberg, S. and Lofstedt, C. (1987). Intra-specific competition in the sex communication channel a selective force in the evolution of moth pheromones. Journal of Theoretical Biology 125 15-24. 

In addition to the extremely low application rates, arthropod pheromones are extremely volatile, are subject to rapid environmental degradation, and are metabolized by enzyme systems present in most living organisms [39, 43]. Most of the USE P -registered products in the U S A are arthropod pheromones and, of those, the majority are straight-chain lepidopteran (butterfly and moth) pheromones (SCLPs). 

This catalytic epoxidation method has been applied to the synthesis of a variety of natural products, particularly polyhydioxylated compounds, including carbohydrates (54) and macrolides. In addition, this reaction has been used for commercial synthesis of disparlure, a gypsy moth pheromone [J. T. Baker Co. (55) and the Shanghai Institute for Organic Chemistry (56)], and more importantly, glycidol, a versatile intermediate for synthesis of /3-blockers and other functionalized chiral molecules (Arco Co.) (Scheme 23) (57). 

In an elegant synthetic application of iron-diene complexes, Knox30 has reported acylation of a series of 1-alkyl-substituted diene complexes which after cleavage, reduction and esterification give a series of moth pheromones (Scheme 11). 

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