Sex Pheromone Analogues Research Articles

Synergism of an insect sex pheromone specialist neuron: Implications for component identification and receptor interactions

Extracellular recordings show that the response to the sex pheromone component, (Z)-7-dodecenyl acetate (Z7-12:Ac) by the HS(a) antennal olfactory specialist neuron of the cabbage looper,Trichoplusia ni (Hübner), is synergized by two synthetic sex pheromone analogs and two components of the female sex pheromone. Complementary behavioral measures of upwind flight and copulatory responses to mixtures ofZ7-12:Ac with the analogs and sex pheromone components in a wind tunnel produced behavioral evidence consistent with the neuron's electrophysiological responses. The phenomenon of receptor neuron synergism impacts several areas and provides a note of caution for common practices of identifying secondary sex pheromone components only from field traps and/or wind tunnel tests.

Moth responses to selectively fluorinated sex pheromone analogs

Partially fluorinated analogs of the European corn borer (Ostrinia nubilalis) female sex pheromone, 11-tetradecenyl acetate (97:3Z:E), having mono- and trifluorsubstitutions at the terminal carbon of the pheromone chain, mimicked the biological activity of the pheromone, while analogs with fluorine at either side of the double bond and a pentafluoro analog were essentially inactive. Comparison of the pheromonal activity of these analogs with the previously reported activity of similarly fluorinated pheromones in five other species of moths revealed an unpredictable relationship between fluorine substitution pattern and pheromone-mimicking activity. Fluorine substitution patterns that rendered pheromonal analogs biologically inactive in the European corn borer had no detrimental influence upon pheromonal activity in other species and the converse was also true. This is evidence that the relative importance of electronic qualities of sites within a pheromone molecule differ from species to species. Furthermore, it indicates that the biochemical components (pheromone receptor proteins, binding proteins, and enzymes) that make up moth olfactory chemosensory systems must also vary structurally from species to species, despite the fact that they are involved in olfactory sensing of compounds having very similar chemical structure.

Synthesis of (Z)-14-Heptadecen-4-olide and (Z)-11-Pentadecen-4-olide, Sex Pheromone Analogues of Ostrinia nubilalis and Cydia molesta

The key step in the preparation of racemic (Z)-14-heptadecen-4-olide (VIa) and (Z)-11-pentadecen-4-olide (VIb), sex pheromone analogues of Ostrinia nubilalis and Cydia molesta, was efficient cross-coupling reaction of 3-methoxycarbonylpropanoyl chloride with corresponding (Z)-alkenylmagnesium bromides. The methyl 4-oxo-(Z)-14-heptadecenoate (Va) and methyl 4-oxo-(Z)-11-pentadecenoate (Vb) prepared in this way were converted by one-pot reaction using sodium borohydride in an ethanolic solution to the required (Z)-alken-4-olides (VIa, VIb).

Metabolically blocked analogs of housefly sex pheromone: I. Synthesis of alternative substrates for the cuticular monooxygenases

Cuticular monooxygenases in the cuticle of the female houseflyMusca domestica oxidize (Z)-9-tricosene to m-9,10-epoxytricosane and to (Z)-9-tricosen-14-one. One possible explanation for these two products is that a single monooxygenase accepts the alkene substrate in two different orientations. Eleven analogs of (Z)-9-tricosene bearing methyl substituents, cyclopropyl groups, fluorine substituents, deuterium substituents, and additional double bonds were synthesized to probe the substrate requirements of this monooxygenase system. In addition, the 11 corresponding epoxides were prepared to aid in identification of the metabolites of each modified alkene.

Metabolically blocked analogs of housefly sex pheromone: II. Metabolism studies

Analogs of (Z)-9-tricosene (Z9-23: Hy) bearing methyl substituents, cyclopropyl groups, fluorine substituents, and additional double bonds were used to probe the substrate requirements for the monooxygenase system that converts Z9-23: Hy to the corresponding epoxide and ketone. Three of the seven analogs tested, 10-fluoro-(Z)-14-tricosene, 10,10-difluoro-(Z)-14-tricosene, and 14-methyl-(Z)-9-tricosene, were metabolized to the corresponding epoxide. Compounds with two methyl groups, a cyclopropane group, a hydroxy group, or an additional double bond at the 14 position were not epoxidized at the 9,10 position. This suggests that only minimal structural change at the 14-position of Z9-23: Hy is allowed with retention of metabolic activity. None of the analogs tested were hydroxylated at the position equivalent to the 14 position of Z9-23:Hy. Of the 13 analogs tested as inhibitors of Z9-23:Hy metabolism, the two compounds that were the most effective inhibitors in both male and female houseflies were (Z)-14-tricosen-10-one and 1-nonyl-1-[(Z)-4-tetradecen-1-yl]-cyclopropane. These data show that the poly substrate monooxy genase that metabolizes Z9-23: Hy in the housefly has very strict structural requirements for the substrate.

European corn borer sex pheromone

The male sexual behavior-stimulating and inhibiting properties of a series of analogs of the European corn borer sex pheromone were determined in a flight tunnel. The structural requirements for inhibition of pheromonal response were far less restrictive than those for elicitation of that response. Analogs that by themselves elicited upwind flight response from males at a low dose were generally less inhibitory to male response than many of the analogs that had no pheromonal activity. These findings suggest that many pheromone analogs bind to pheromone receptors without provoking behavioral response and possibly undergo slower degradation on the antenna than pheromonally active compounds. The disparity of response to analogs by two pheromonal types of the European corn borer indicates that the pheromone receptor and pheromone catabolic systems are biochemically very different in the two types.

Analogs of sex pheromone of processionary moth,Thaumetopoea pityocampa: Synthesis and biological activity

The synthesis and biological activity of some analogs of (Z)-13-hexadecen-11-ynyl acetate1, the major component of the sex pheromone of the processionary mothThaumetopoea pityocampa is described. The analogs have been formally derived by structural modification of the enyne and acetate functions of the parent compound1. In field tests, trifluoroacetate ester16 and the analog,11, with fluorine substitution at the olefin site, decreased the pheromone action, whereas epoxy derivative,10, from epoxidation of the olefin moiety in1, and propionate ester15 gave synergistic activity. The formate14 had a variable effect according to the composition of the lure. Formal reduction of the enyne to give the acetylene2 was found to retain activity. Alcohols12 and13, resulting from hydrolysis of the enyne1 and acetylene2, respectively, inhibited the action of their parent compounds.

Synthesis and field bioassay of some analogs of sex pheromone of citrus mealybug,Planococcus citri (Risso)

A series of structural analogs of (s+)-cis-(1R)-3-isopropenyl-2,2-dimethylcyclobutanemethanol acetate, sex pheromone of the citrus mealybug,Planococcus citri (Risso), was synthesized. The analogs were tested in a field bioassay in order to determine the structure-activity relationships of the pheromone. All changes in structure reduced the activity of the test compounds, to various degrees. The most active analog tested was the homolog (+)-cis-(1R)-3-isopropenyl-2,2-dimethylcyclobutaneethanol acetate (IV), whose activity, at a higher dosage, was comparable to that of the pheromone. The alcohol (+)-cis-(1R)-3-isopropenyl-2,2-dimethylcyclobutanemethanol was tested in mixtures with the pheromone and found to be neither an inhibitor nor a Synergist. The results show that all functional groups of the pheromone molecule are essential for optimal biological activity.

Electroantennograms and Trapping with Spruce Budworm (Lepidoptera: Tortricidae) Sex Pheromone Analogues

Electroantennograms (EAGs) were obtained from male spruce budworm, Choristoneura fumiferana (Clemens), for 42 of 45 sex pheromone analogues, differing in a variety of structural features. Maximum amplitude, duration, and shape of the EAGs were noted. Also, 29 analogues were tested for attractiveness in baited traps and for an effect on synthetic sex pheromone attractiveness when admixed with pheromone in the lure. One analogue caught more than control, but less than pheromone, whereas 22 analogues decreased, and one increased, expected pheromone trap catch.

Electroantennogram Activities of Sex Pheromone Analogues and their Synergistic Effect on Field Attraction in the Diamondback Moth

Electroantennogram Activities of Sex Pheromone Analogues and their Synergistic Effect on Field Attraction in the Diamondback Moth

Syntheses of female sex pheromone analogues of the german cockeroach and their biological activity.

Several analogues of 3,1l-dimethyl-2-nonacosanone, one component of the sex pheromone of the German cockroach, were synthesized. Their activity for the male to raise his wings was assayed and summerized in Tables I and II.

Measuring Release Rates of Pheromone Analogues and Synergists from Polyethylene Caps 1

A method was devised for the rapid determination of release rates of various sex pheromone analogues and synergists from wicks of insect traps. Acetates, similar to known attractants and synergists, were synthesized with acetyl-1-C-chloride and the loss of chemical from polyethylene cap wicks was determined by radioassay techniques. Chain length and presence of polar substituents on the acetate, temperature, air movement, and amount of material placed in the cap were all important factors governing the release rate. Caps in traps under field conditions released dodecyl and tetradecyl acetate at an average rate of about 5 μg per hr.

Studies in pheromone chemistry : Analogs of a heterocyclic insect sex pheromone

A group of structural analogs of the male butterfly pheromone I has been prepared for biological testing. Some conformational and stereochemical features of these compounds are discussed.