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Huanglongbing (HLB) is the most destructive disease of citrus worldwide. The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), is the vector of the phloem-inhabiting bacterium, Candidatus Liberibacter asiaticus, which is presumed tocauseHLBinFloridacitrus.Laboratoryandfieldstudieswereconductedtoexaminethe behavioral responses of male and female D. citri to their cuticular extracts. In olfactometer assays, more male D. citri were attracted to one, five, or 10 female cuticular extract equivalent units than blank controls. The results were confirmed in field studies in which clear or yellow traps baited with 10 female cuticular extract equivalent units attracted proportionately more males than clear traps baited with male cuticular extract or unbaited traps. Analyses of cuticular constituents of male and female D. citri revealed differences betweenthesexesinchemicalcompositionoftheircuticularextracts.Laboratorybioassays with synthetic chemicals identified from cuticular extracts indicated that dodecanoic acid attracted more males than clean air. Traps baited with dodecanoic acid did not increase total catch of D. citri as compared with blank traps at the dosages tested; however, the sex ratio of psyllid catch was male biased on traps baited with the highest lure loading dosage tested (10.0 mg).

The discovery that the eastern tent caterpillar Malacosoma americanum (F.) causes mare reproductive loss syndrome (MRLS), and thus has the potential to continue to result in major economic losses to the equine industry of Kentucky, has resulted in an intensive effort to identify practical means to monitor and control this defoliator, including these experiments to optimize a sex pheromone trap for this pest. A pheromone-baited delta trap with a large opening, such as InterceptST Delta, was more effective than other tested traps. Orange delta traps caught more moths than other tested colors. ETC males are caught at all tested heights within the tree canopy. For monitoring flights, setting traps at 1.5 m would allow easy counting of moths. A 9:1 blend of (E,Z)-5,7-dodecadienal (ETC-Ald) and (E,Z)-5,7-dodecadienol (ETC-OH) was most effective in capturing males. Increasing loading doses of a 3:1 blend (Ald:OH) resulted in the capture of increasing numbers of moths, but a 9:1 blend was more effective than 3:1 blend even at a nine-fold lower loading rate. Pheromone-impregnated white septa caught more moths than gray septa at the same loading dose. The advantages and limitations of using pheromone traps for monitoring M. americanum are discussed.

The citrus mealybug, Planococcus citri (Risso) is a common pest in the Southern U. S. and the Mediterranean. Two alternative syntheses of the female sex pheromone, (1R)-(+)-cis-2,2-dimethyl-3-isopropenyl-cyclobutane methanol acetate, have been developed. Key transformations include an allylic oxidation of (1R)-(+)-alpha-pinene to (+)-R-verbenone, oxidative decarboxylation using RuCl(3)-NaIO(4), and methylenation with Zn/CH(2)Br(2)/TiCl(4).

The potential utility of micrometer-sized particles as controlled-release devices for the volatilization of insect pheromones for mating disruption applications is evaluated in this study for two pheromone/model compound systems (codlemone/1-dodecanol and disparlure/1,2-epoxyoctadecane). To expedite the measurement of release rates from these particle devices, two techniques based on thermogravimetric analysis (TGA) have been exploited: isothermal TGA (I-TGA) at elevated temperatures (40-80 degrees C) with N(2) convection and volatilization temperature (VT) by dynamic TGA. A correlation between these two methods has been established. Samples that exhibit a higher VT provide a lower release rate from a particle substrate. Using these techniques, it has been demonstrated that chemical interactions between adsorbed liquids and particle surfaces may play a small role in defining release characteristics under conditions of low surface area, whereas parameters associated with total surface area and micropore structure appear to be much more significant in retarding evaporation for uncoated particles containing an adsorbed liquid. Additional regulation of release rates was achieved by coating the particle systems with water-soluble or water-dispersible polymers. By careful selection of particle porosity and coating composition, it is envisioned that the evaporation rate of pheromones can be tailored to specific insect control applications.

The pecan nut casebearer, Acrobasis nuxvorella (Neunzig), is a significant pest of the pecan nut industry. Two alternative syntheses of (9E, 11Z)-hexadeca-9,11-dienal, the sex pheromone of the pecan nut casebearer, are described. The key transformation in each sequence is an orthoester Claisen rearrangement.

The synthesis of the polypropionate-derived pheromones sitophilate (1) and sitophilure (2) are described using an asymmetric aldol condensation as the key step to adduct 6; compound 6 was smoothly converted to the antipodes of each pheromone. This procedure can be expanded to more complicated structures with the same type of syn configuration such as stegobinone (3) and serricornin (4).

Volatiles from green ash foliage or ambient air was trapped by Super Q and their chemical identities determined by GC−MS analysis. Effects of the whole mixture and individual chemical components of green ash volatiles on gypsy moth larval (GML) locomotory behavior were assayed in a T-tube arena. Green ash volatiles (treatment) proved significantly repellent to GML as compared to Super Q trappings of volatiles from the ambient air (control). Such observed effects were due to the combined repellencies of linalool, methyl salicylate, and farnesenes; however, the relatively major component, trans-ocimene, proved to be nonrepellent. The significance of such volatiles in GML orientation and host/nonhost decision is discussed. Keywords: Gypsy moth; green ash; repellency; volatiles; chemical identification

The four possible optical isomers of matsuone ( 1 ), female sex pheromone of Matsucoccus resinosae pine scales, were convergently synthesized in high optical purities. The absolute configuration of the natural product has been assigned as (2 E , 4 E , 6 R , 10 R )-4,6,10,12-tetramethyltridecan-2,4-dien-7-one. Bioassays with M. resinosae using these stereoisomers reveal that the unnatural (6 R , 10 S )-isomer mimics the natural pheromone.

North American beaver (Castor canadensis) were observed to sniff from the water and make land visits to some synthetic chemical components of castoreum placed on experimental scent mounds (ESM). In previous analysis, the elicitation (presence/absence), completeness, and/or strength (number, duration) of these key responses served as separate measures of biological activity. In this paper, we used principal components analysis (PCA) to combine linearly six related measures of observed response and one index of overnight visitation calculated over all trials. The first principal component accounted for a majority of the variation and allowed ranking of the samples based on their composite bioactivity. A second PCA, based only on response trials (excluding trials with no responses), showed that responses to the synthetic samples, once elicited, did not vary greatly in completeness or strength. None of the samples evoked responses as complete or strong as the castoreum control. Castoreum also elicited more multiple land visits (repeated visits to the ESM by the same individual or by more than one family member) than the synthetic samples, indicating that an understanding of the castoreum chemosignal requires consideration of responses by the family unit, and not just the land visit by the initial responder.

Huanglongbing (HLB) is the most destructive disease of citrus worldwide. The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), is the vector of the phloem-inhabiting bacterium, Candidatus Liberibacter asiaticus, which is presumed to cause HLB in Florida citrus. Laboratory and field studies were conducted to examine the behavioral responses of male and female D. citri to their cuticular extracts. In olfactometer assays, more male D. citri were attracted to one, five, or 10 female cuticular extract equivalent units than blank controls. The results were confirmed in field studies in which clear or yellow traps baited with 10 female cuticular extract equivalent units attracted proportionately more males than clear traps baited with male cuticular extract or unbaited traps. Analyses of cuticular constituents of male and female D. citri revealed differences between the sexes in chemical composition of their cuticular extracts. Laboratory bioassays with synthetic chemicals identified from cuticular extracts indicated that dodecanoic acid attracted more males than clean air. Traps baited with dodecanoic acid did not increase total catch of D. citri as compared with blank traps at the dosages tested; however, the sex ratio of psyllid catch was male biased on traps baited with the highest lure loading dosage tested (10.0 mg).

Abstract. Assortative mating based on a courtship signal was investigated by examining the relationship between the male-produced pheromone and female preference in the bark beetle, Ips pini. Female preference in response to the male-produced pheromone was measured in the field using traps baited with a range of 11 synthetic blends of the two pheromone enantiomers, (+) and (-)ipsdienol. The production of ipsdienol enantiomers was measured from individual, live-trapped male beetles in the laboratory. Although there was a significant regression of the blend that male beetles produced and the blend to which they responded, the sex ratios of beetles responding to different blends of enantiomers in the field did not differ significantly. In a second experiment, male female pairs were sampled in the field, females were assayed for preference in a laboratory olfactometer, and male enantiomer production was measured in the laboratory. There was a significant correlation between female preference and male blend production. Pheromone production and response were not correlated with body size, nor was body size correlated in male-female pairs.

Wood cockroaches in the genus Parcoblatta , comprising 12 species endemic to North America, are highly abundant in southeastern pine forests and represent an important prey of the endangered red-cockaded woodpecker, Picoides borealis . The broad wood cockroach, Parcoblatta lata , is among the largest and most abundant of the wood cockroaches, constituting >50% of the biomass of the woodpecker's diet. Because reproduction in red-cockaded woodpeckers is affected dramatically by seasonal and spatial changes in arthropod availability, monitoring P. lata populations could serve as a useful index of habitat suitability for woodpecker conservation and forest management efforts. Female P. lata emit a volatile, long-distance sex pheromone, which, once identified and synthesized, could be deployed for monitoring cockroach populations. We describe here the identification, synthesis, and confirmation of the chemical structure of this pheromone as (4 Z ,11 Z )-oxacyclotrideca-4,11-dien-2-one [= (3 Z ,10 Z )-dodecadienolide; herein referred to as “parcoblattalactone”]. This macrocyclic lactone is a previously unidentified natural product and a previously unknown pheromonal structure for cockroaches, highlighting the great chemical diversity that characterizes olfactory communication in cockroaches: Each long-range sex pheromone identified to date from different genera belongs to a different chemical class. Parcoblattalactone was biologically active in electrophysiological assays and attracted not only P. lata but also several other Parcoblatta species in pine forests, underscoring its utility in monitoring several endemic wood cockroach species in red-cockaded woodpecker habitats.

Female brownbanded cockroaches, Supella longipalpa, emit a sex pheromone that attracts males from a distance. This pheromone was isolated and identified as 5-(2,4-dimethylheptanyl)-3-methyl-2H-pyran-2-one (which we refer to as supellapyrone), and its structure was confirmed by synthesis. A racemic blend of the synthetic compound elicited behavioral and electrophysiological responses comparable to the natural pheromone across a range of doses. This compound is not only a very different type of cockroach pheromone but also makes up an additional class of natural products--namely, 3,5-dialkyl-substituted alpha-pyrones.

The four possible optical isomers of matsuone ( 1 ), female sex pheromone of Matsucoccus resinosae pine scales, were convergently synthesized in high optical purities. The absolute configuration of the natural product has been assigned as (2 E , 4 E , 6 R , 10 R )-4,6,10,12-tetramethyltridecan-2,4-dien-7-one. Bioassays with M. resinosae using these stereoisomers reveal that the unnatural (6 R , 10 S )-isomer mimics the natural pheromone.

A convergent, general synthesis of (2E,4E)-4,6,10,12-tetramethyltrideca-2,4-dien-7-one (matsuone, 1) and five closely related analogs (2–6), which serve as sex pheromone components of female Matsucoccus pine scales, is described. The aldehydes 8a and 8b were obtained via a reaction sequence in which the key step is a [2,3]-Wittig sigmatropic rearrangement of the oxazoline ether of bisallylic tertiary alcohol 11. Coupling of 8 with the appropriate nucleophilic reagents, followed by oxidation of the resultant secondary alcohols, afforded the pheromone components 1–6.

The social cohesiveness of eusocial insect colonies is maintained primarily through the utilization of pheromones. In this study we quantitatively elucidated the production, secretion, and transmission of 9-keto2(E)-decenoic acid (9-ODA), one of the components of the mandibular gland pheromone of the honey bee queen Apis mellifera; this is the only identified primer pheromone complex in the eusocial insects. Mated queens produce 12–400 μg of 9-ODA/day, or between 10% and 170% the average amount found in the glands at any one time. Approximately 0.5 μg of 9-ODA is maintained on the body surface of queens by an equilibrium between exudation, internalization, tracking on the comb, and removal by workers. Retinue bees, attending the queen, remove the greatest amount, although the role of the wax as both a sink and a medium for pheromone transfer has been previously underestimated. Only about 1 in 10 retinue workers pick up substantial quantities of pheromone while attending the queen and, within seconds, most of the acquired 9-ODA is found externally on the abdomen, or in the gut. These attendants, also called messenger bees, transfer 9-ODA to other workers, mostly through direct contacts, but also via the wax. A model evaluating the pathways and relative quantities of 9-ODA transferred throughout the nest is presented. As well as being important for a basic understanding of the system, the results have implications for the proper design and use of pheromones in bee management.

A new pheromone component, lanierone, (2-hydroxy-4,4,6-trimethyl-2,5-cyclohexadien-1-one) was isolated and identified from a Porapak Q collection of volatiles from maleIps pini from New York through GC fractionation, bioassay, and spectrometry. In both the laboratory and the field, synthetic lanierone, in a 1:100 ratio with synthetic ipsdienol, is as attractive as natural pheromone sources. Synthetic ipsdienol alone is not attractive in the laboratory and only weakly attractive in the field. Varying the ratio of lanierone to ipsdienol in the field from 10(-4)∶1 to 1∶1 in 10-fold increments resulted in an increased number of beetles trapped at the three lower ratios, but also in an increase in the proportion of males trapped. In the field, all combinations of lanierone to ipsdienol attracted proportionately fewer males than did pheromone-producing male beetles. GC and GC-MS analyses of Porapak Q-trapped volatiles revealed that lanierone is produced in an amount equal to about 0.2% of that of ipsdienol and is produced exclusively by males. The small amount of lanierone produced, together with a GC retention time similar to that of ipsdienol on a nonpolar column, probably confounded its detection in earlier studies.

Matsunone, (2E,4E)-4.6,10,12-tetramethyl-2,4-tridecadien-7-one, is the primary sex pheromone ofMatsucoccus resinosae, M. thunbergianae, andM. matsumurae. The synthetic compound was tested in the laboratory and in field tests with all three species, and significantly more males responded to synthetic matsuone than to controls. The attraction of synthetic matsuone to males in field tests was not significantly different from that of virgin females at the same matsuone release rate. An analog of matsuone previously shown to be biologically active was also tested in the laboratory withM. resinosae andM. thunbergianae, and field tested withM. resinosae. The active analog required a dose approximately 100 times greater than matsuone to yield maximum laboratory bioassay response, and in field tests, attraction was not significantly different from controls at doses at which matsuone was significantly attractive.

The sex pheromone of the German cockroach, Blattella germanica , has been characterized as gentisyl quinone isovalerate. This cockroach is a major cause of allergic disease and serves as a mechanical vector of pathogens, making it one of the most important residential and food-associated pests worldwide. The sex pheromone–producing gland in adult females was identified in 1993, but thermal instability of the pheromone made characterization difficult. Now, using a new preparative gas chromatography approach coupled with electroantennographic detection, we have isolated and characterized the pheromone, which we term blattellaquinone, and confirmed the identification by chemical synthesis. The synthetic pheromone was active in behavioral assays and highly effective in field trapping tests, which suggest that it may provide a new tool in cockroach population detection, monitoring, and control.

A simple, inexpensive, and highly efficient NMR sample preparation technique for volatile chemicals has been devised using a micropreparative GC system. The recovery efficiency of a volatile chemical using this technique was80% with sample sizes of 0.05 to 0.5 microg. The purity of the acquired NMR samples was sufficient for high sensitive NMR analyses including two dimensional experiments.

Hydrogenation of 4-cholesten-3-one (1) with tritium gas over palladium black in pyridine afforded [β-4,5- 3 H]-cholestan-3-one (2a). Tritium NMR showed that there was a mixture of tritiated compounds formed, 2a-2c ; the latter two containing small amounts of protium substitution. Tritium NMR also indicated that none of the unwanted α-diastereomer was formed.

Chemical analysis (high-performance liquid chromatography) and bioassay demonstrated the presence of compounds that seem to be components of the Ixodes scapularis arrestment pheromone. Only two purines, guanine and xanthine, were found in acidified saline extracts made from cast skins after molting of fed nymphs, fed larvae, and fecal/excretory exudates deposited by unfed adults on substrates in their environment. The ratio of guanine to xanthine was 10.6:1 in an extract from the nymphal skins versus 0.95:1 in an extract from the larval skins. Guanine, xanthine, and traces of a third purine, tentatively identified as 8-azaguanine, were found in extracts made from filter paper strips or washings from glass vials contaminated with tick feces and excreta left by unfed adults. 8-azaguanine may be a product of microbial degradation of the other purines rather than a natural product from the ticks. Low concentrations of ammonia also were detected in saline extracts of excreta from feeding ticks. Hematin also was found in NH4OH extracts of the black fecal/excretory exudates deposited by the unfed ticks. Hematin was tentatively identified by comparison of spectra with that of the authentic standard. Bioassays demonstrated a strong positive arrestment response to cast skins found to contain a mixture of guanine and xanthine and to black fecal/excretory exudates containing guanine, xanthine, the putative 8-azaguanine, and hematin. A Noldus video tracking system using a CCD video camera and Ethovision Pro tracking software showed statistically significant increases in the frequency of visits to the treated zone versus the control. Ticks were significantly more likely to assemble in response to the tick exudates within as little as 3 h compared with the controls. Previous bioassay studies also showed strong positive responses to guanine, xanthine, other purines, and hematin. Comparisons with the arrestment pheromones of other tick species are described. The inclusion of the pheromone components in a permethrin-impregnated oily matrix, Last Call, increased the lethal activity of the product to 95% compared with only 65% in the formulation with permethrin alone. More detailed knowledge of I. scapularis arrestment pheromone may be useful for improving the efficacy of this tick-killing technology even further.

The pecan nut casebearer, Acrobasis nuxvorella (Neunzig), is a significant pest of the pecan nut industry. Two alternative syntheses of (9E, 11Z)-hexadeca-9,11-dienal, the sex pheromone of the pecan nut casebearer, are described. The key transformation in each sequence is an orthoester Claisen rearrangement.

A convergent, enantioselective synthesis of (−)-matsuone (1, (2E,4E,6R,10R)-4,6,10,12-tetramethyl-2,4-tridecadien-7-one), the primary sex attractant pheromone of the red pine scale Matsucoccus resinosae, is described

Female cowpea weevils,Callosobruchus maculatus, produce a sex pheromone that elicits orientation and sexual behavior in males. Bioassay-directed isolation of the sex pheromone was conducted and compounds in the active fraction were identified and synthesized. Volatiles were collected from individual virgin females by adsorption on filter paper dises and hexane extraction. A bioassay was used in which the locomotory response of single males in glass vials was recorded upon exposure to treatments or controls. Crude extracts were subjected to silica gel column chromatography with solvents of increasing polarity; all activity eluted with methanol. Activity in the highly polar methanol fraction suggested a carboxylic acid or a compound with multiple polar functionality. Acid-base partitioning of the crude extract isolated all activity in the acid fraction, confirming that the pheromone was a carboxylic acid. The acid fraction was further fractionated by preparative GC with a Carbowax column. The most active GC fraction contained the following five 8-carbon acids identified by GC-MS and comparison with synthetic candidates: 3-methyleneheptanoic acid, (Z)-3-methyl-3-heptenoic acid, (E)-3-methyl-3-heptenoic acid, (Z)-3-methyl-2-heptenoic acid, and (E)-3-methyl-2-heptenoic acid. Each of the synthetic acids was active individually for males, and combinations of two or more of the acid pheromones had an additive effect. Upwind flight responses to natural and synthetic pheromones were observed in a flight tunnel. (Z)-3-Methyl-2-heptenoic acid was previously identified as the sex pheromone for the relatedC. analis, but this and the other four acid pheromones fromC. maculatus were inactive for maleC. analis. There was no cross-attraction betweenC. maculatus andC. analis in reciprocal studies using extracted volatiles from females of both species, GC-MS analysis ofC. analis female volatiles failed to detect any of theC. maculatus compounds but did find an unidentified C-8 acid with a GC retention time different from any of theC. maculatus pheromones.

North American beavers (Castor canadensis) mark their territories with castoreum, the strong-smelling paste in their castor sacs. In their own territories, beavers respond with scent marking to experimental scent marks that consist of strange castoreum (or selected components). In part, the unique odor of castoreum is due to large amounts of phenolic compounds and neutral compounds. Purified neutral compounds were analyzed by GC. GC-MS, and NMR; identities of the neutral compounds were confirmed by comparing the properties of authentic compounds with those of the isolated compounds. We identified 13 neutral compounds that had not been reported before for castoreum. Most of these are oxygen-containing monoterpenes. Of the nine neutral compounds reported by Lederer (1949), only three are confirmed in our analysis; the other six neutral compounds are either absent or are not volatile enough to be detected by our methods. Eight compounds—6-methyl-l-heptanol, 4,6-dimethyl-l-heptanol, isopinocamphone, pinocamphone, two linalool oxides, and their acetates—were synthesized for structure identification and bioassays.

North American beaver (Castor canadensis) mark their territories with castoreum, a chemically complex secretion from their castor sacs. The phenolic and neutral fractions of castoreum have been shown to elicit specific behavioral responses from beavers in a field setting. Our objective was to identify compounds/mixtures that evoked responses similar to those stimulated by castoreum. We assayed recently identified phenolic compounds, some phenolics that had been determined to be biologically active in previous studies, the neutral compound borneol, and combinations of phenolic compounds, neutral compounds, and the two combined. Biological activity was measured by the elicitation and extent of specific responses and their strength (duration, frequency, and proportion of beavers responding). Generally, single compounds stimulated fewer responses than mixtures. A 26-compound mixture of phenolic and neutral compounds elicited responses in a similar proportion of trials as castoreum. However, responses to castoreum were stronger than to any synthetic sample. Further investigation of different measures of response, namely, elicitation, completeness, and strength, are deemed necessary to fully decipher the design of social odors.

Grandisol (cis-2-isopropenyl-1-methylcyclobutaneethanol) and its corresponding aldehyde, grandisal, were previously isolated and identified as aggregation pheromone components forPissodes strobi (Peck) andP. nemorensis Germar, but the enantiomeric ratios produced by these insects were not previously determined. We isolated grandisol and grandisal from males of bothP. strobi andP. nemorensis. The insect-produced grandisol was derivatized with trifluoroacetic anhydride, and the enantiomeric composition was determined by gas chromatography on an optically active cyclodextrin glass capillary column. The insect-produced grandisal was first reduced to grandisol before derivatization.P. nemorensis produced nearly 100% (1R,2S)-grandisol and nearly 100% (1S,2R)-grandisal.P. strobi produced 99% (1R,2S)-grandisol and approximately 60% (lR,2S)-grandisal. In electroantennogram (EAG) studies with liveP. nemorensis andP. strobi, no significant differences were found between the responses of males and females to racemic grandisol, racemic grandisal, or the 1R,2S and 1S,2R enantiomers of grandisol and grandisal, which is consistent with previous assertions that these compounds are aggregation pheromones. Although no studies to date withP. strobi have demonstrated a behavioral response to grandisol and grandisal,P. strobi antennae detected all enantiomers of grandisol and grandisal tested in EAG tests. The antennae of P.nemorensis responded significantly more to (1R,2S) grandisal than to (1S,2R)-grandisal, despite producing only (1S,2R)-grandisal.

North American beaver (Castor canadensis) mark their territories with castoreum, the contents of their castor sacs. In their territories, beaver respond with scent marking to experimental scent marks consisting of castoreum, or selected single components. In part, the unique odor of castoreum is due to large amounts of phenolic compounds. Purified phenolic components were analyzed by GC, GC-MS, and NMR; identifications were confirmed by comparing the spectra of synthetic phenols with those of the isolated phenols. Of the 15 phenols reported elsewhere, only five were confirmed in our analysis; the other 10 phenolic compounds are either absent or are not volatile enough to be detected by our methods. In addition, 10 phenolic compounds have been identified in this study that were not reported in the previous papers concerning the constitution of castoreum.

Five doses of lanierone (2-hydroxy-4,4,6-trimethyl-2,5-cyclohexadien-1-one) were tested with one dose of enantiomerically pure [99.4% (4R)-(−)] ipsdienol (2-methyl-6-methylene-2,7-octadien-4-ol) for activity as an aggregation pheromone ofIps pini (Say) in California. The response ofI. pini to 1 mg/day ipsdienol + 20 μg/day lanierone was significantly greater than the response to ipsdienol alone, but the response pattern did not demonstrate a clear dose-response relationship. The response to the highest dose of lanierone (2 mg/day) was significantly lower than the response to ipsdienol alone. Ipsdienol attracted significantly moreI. pini than a male-infested log. Lanierone did not alter the percentage of maleI. pini responding to ipsdienol alone. Neither sex ofI. pini orDendroctonus brevicomis LeConte from California produced detectable amounts of lanierone, but myrcene-aerated maleD. brevicomis produced 97.8%-(4S)-(+)-ipsdienol. The black-bellied clerid,Enoclerus lecontei (Wolcott) (Coleoptera: Cleridae) was attracted to lanierone when released with ipsdienol. Neither compound was attractive when released alone, proving synergism for the kairomone of this predator. Lanierone did not influence the response of the predatorsTemnochila chlorodia (Mannerheim) (Coleoptera: Trogositidae) andEnoclerus sphegeus (F.) (Coleoptera: Cleridae), which were attracted to all treatments containing ipsdienol.Tomicobia tibialis Ashmead (Hymenoptera: Pteromalidae) responded in significantly greater numbers to the male-infested log than it did to ipsdienol or ipsdienol + 20 μg/day lanierone.

Synthese a partir de l'acide oxo-3 cyclohexene-1 carboxylique, l'etape-cle etant la separation de deux carboxamides bicycliques

A short synthesis of [4,5-(3)H2] (E)-9-oxo-2-decenoic acid (ODA), a high-specific-activity tritium-containing isotopomer of the queen bee pheromone, is described. Catalytic tritiation of the ketal of ethyl 9-oxo-4-decenoate introduces tritium into two positions, one of which is completely unactivated. Subsequent transformation by selenation, oxidation, and hydrolysis affords the labeled 9-ODA at60 Ci/mmol. The material is suitable for biochemical studies of binding and catabolism in ovarian, antennal, and other target tissues.

α-Methylbenzylamides, useful intermediates in the resolution of carboxylic acids, are cleaved with a two step procedure; enolizable amides are not racemized.

Matsucoccus resinosae in the United States,M. matsumurae in China, andM. thunbergianae in Korea use (2E, 4E)-4,6,10,12-tetramethyl-2,4-tridecadien-7-one (1) (matsuone) as the primary component of their sex attractant pheromones. The structure was postulated from mass and NMR spectra and confirmed by synthesis of analogs3, (2E,4E)-4,6,11,12-tetramethyl-2,4-tridecadien-7-one, and4, (2E,4Z)-4,6,11,12-tetramethyl-2,4-tridecadien-7-one. Both analogs were attractive to the males ofM. resinosae in laboratory bioassays and toM. matsumurae in laboratory and field tests, but the 4Z analog (4) was much less so than the 4E analog (3) and had inhibitory effects at high concentrations. Dodecanol, isolated from aeration and solvent extracts of femaleM. resinosae, evoked characteristic wing-raising by pedestrian males, but the role of this response was not determined.

This paper describes the current status and discuss the validity of the fluorescent particle (FP) tracer technique. Properties of the material itself, the blower generator, membrane filter, drum impactor, and Rotorod samplers, and of counting techniques, are described. The inherent and operational errors involved are evaluated, and evidence on the atmospheric diffusion, fallout and impaction, and fluorescent stability of the particles is presents. It is concluded that in the present state of development of the technique the errors, in terms of 90% confidence Intervals, are approximately ±5–10% for source strength determination, ±10–12% (if 300 particles are counted) for dosages determined by the Rotorod, and ±17–20% for dosages determined by the membrane filter sampler. The effects of atypical diffusion on the validity of the method appear to be insignificant, and fluorescence losses may be controlled by proper selection of materials. For ground releases the losses by fallout and impaction may am...

An efficient method is reported of synthesizing relatively large quantities of methyl 3-oxo-1-cyclohexenecarboxylate (2b), a useful dienophile and photoreagent, from m-anisic acid (3) through the Birch reduction. Treating 3 with lithium in liquid ammonia produces any one of the four specific 3-oxocyclohexene carboxylic acids depending on the conditions selected.

Synthese en particulier d'acides oxo-5 dimethyl-3,3 caproique, methyl-4 oxo-6 oenanthique, methyl-3 adipique, acetyl-3-dimethyl-2,2- et carboxy-3 dimethyl-2,2 cyclobutaneacetique