Stereoisomers of 4-methyl-3-heptanol (MH) are pheromone components of several Scolytus bark beetles. The elm bark beetle Scolytus laevis (Coleoptera: Scolytidae) has in previous studies been caught in traps baited with commercial MH containing all four stereoisomers, but the lure has been considered a weak attractant. In this study, we addressed the question whether stereospecific responses by S. laevis to stereoisomers of MH might contribute to its niche separation from other sympatric Scolytus species. Using GC–MS, we analyzed extracts of hindguts and abdomens from male and female S. laevis and the sympatric S. triarmatus. We also tested all four MH-stereoisomers individually and in combinations in the field to determine their role for S. laevis. All four stereoisomers were synthesized via a boronic ester method with 1,2-dicyclohexylethanediol as chiral director. In addition, the (3S,4R)-stereoisomer of MH was prepared through enantioselective, lipase-mediated transesterification of a mixture of the four stereoisomers of MH. Females of both species contained small amounts of syn-MH, and males contained trace amounts of anti-MH. The anti stereoisomer (3R,4S)-MH was attractive to male and female S. laevis, whereas the syn stereoisomer (3S,4S)-MH acted as an inhibitor or deterrent and reduced the catch when added to the attractive isomer. The syn isomer is the main aggregation pheromone component of the larger and sympatric S. scolytus and possibly also of S. triarmatus. The avoidance response of S. laevis to the (3S,4S)-stereoisomer may reduce interspecific competition for host trees.

Synthesis of racemic lineatin (1), a pheromone component of Trypodendron lineatum, is described. Condensation of 5-methyl-5-hexen-2-one (2) and triethyl phosphonoacetate with LiN(SiMe3)2 gave esters 3, which upon hydrolysis gave acids 4a-f. The bicyclo[3.2.0] ring compounds 5 and 6 were obtained via an intramolecular [2 + 2] addition by refluxing underivatized carboxylic acids 4a-f with NaOAc and Ac2O. Compound 5 was isomerized to the thermodynamically more stable isomer 6 using a Pd/C catalyst activated with hydrogen. Reduction of 6 with LiAlH4 gave the endo and exo isomers 7a and 7b (4:1). Isolation of the alcohol 7a followed by acetylation gave 8. Subsequent oxidation with OsO4 and methylmorpholine N-oxide gave diol 9. Cleavage of 9 with H5IO6 in diethyl ether gave keto aldehyde 10, which was converted to keto acetal 11. Treatment of 11 with MeMgBr followed by acidic workup gave 1. The overall efficiency is approximately 20%.

Bioleaching of metal sulfide ores involves acidophilic microbes that catalyze the chemical dissolution of the metal sulfide bond that is enhanced by attached and planktonic cell mediated oxidation of iron(II)-ions and inorganic sulfur compounds. Leptospirillum spp. often predominate in sulfide mineral-containing environments, including bioheaps for copper recovery from chalcopyrite, as they are effective primary mineral colonizers and oxidize iron(II)-ions efficiently. In this study, we demonstrated a functional diffusible signal factor interspecies quorum sensing signaling mechanism in Leptospirillum ferriphilum and Leptospirillum ferrooxidans that produces (Z)-11-methyl-2-dodecenoic acid when grown with pyrite as energy source. In addition, pure diffusible signal factor and extracts from supernatants of pyrite grown Leptospirillum spp. inhibited biological iron oxidation in various species, and that pyrite grown Leptospirillum cells were less affected than iron grown cells to self inhibition. Finally, transcriptional analyses for the inhibition of iron-grown L. ferriphilum cells due to diffusible signal factor was compared with the response to exposure of cells to N- acyl-homoserine-lactone type quorum sensing signal compounds. The data suggested that Leptospirillum spp. diffusible signal factor production is a strategy for niche protection and defense against other microbes and it is proposed that this may be exploited to inhibit unwanted acidophile species.

Identification of the sex pheromone of Cydia splendana (Lepidoptera, Tortricidae) bypheromone gland analysis followed by field trapping with synthetic compounds showsthe occurrence of two pheromone races. Acorn moth females from Sweden, whereoak Quercus robur is the only host plant, use a blend of the E,Z and E,E isomers of8,10-dodecadien-1-yl acetate. In Central and Southern Europe, where C. splendana feedson chestnut Castanea sativa and several species of oak, males respond to another isomerblend, E,E and Z,E. The distribution of the two pheromone races of C. splendana overlapsin Northern France, where they share oak as plant host. Differences in sex communicationsignals between these populations of C. splendana corroborate the role of specific materecognition in speciation events.

N-Iodosuccinimide (NIS) in pure trifluoroacetic acid (TFA) offers a time-efficient and general method for the iodination of a wide range of mono-and disubstituted benzenes at room temperature, as demonstrated in this paper. The starting materials were generally converted into mono-iodinated products in less than 16 hours at room temperature, without byproducts. A few deactivated substrates needed addition of sulfuric acid to increase the reaction rate. Another exception was methoxybenzenes that preferentially were iodinated by NIS in acetonitrile with only catalytic amounts of TFA.

In this paper the phase behaviour and physical properties of a series of alkyl (C-6, C-8, C-12 and iso-C-8) monoglycerol ethers and 2-hydroxyalkyl (C-6, C-8, C-12) monoglycerol ethers are presented. The binary phase diagram for the surfactants shows very little dependence on temperature. Ir can be seen that as the alkyl chain length increases the tendency to form lamellar liquid crystalline phases increases. The branched alkyl chain shows no formation of lamellar phases even at high concentrations of surfactant. The difference in phase behaviour between the surfactants is attributed to the variation in the critical packing parameter (CPP) of the surfactants. The presence of an additional hydroxyl group in the alkyl chain causes temperature-independent solubility behaviour. Ternary phase diagrams were prepared using dodecane as the oil phase. Hexyl glycerol ether was the only one of the alkyl glycerol ethers that was sufficiently water-soluble to determine the surface tension and c. m. c. The c. m. c. was determined as 15 mM (and surface tension as 26 mN m(-1)).

Hydrolysis of labile esters of beta-hydroxyketones has been performed with whole plant tissue from various vegetables. The pheromone 5-hydroxy-4-methyl-3-heptanone (1) was used as the model compound. Hydrolysis of acetates and benzoates of 1 was unsuccessful using normal conditions of ester hydrolysis, both by chemical hydrolysis and by the means of commercial lipases. When, however, whole cells of carrot, celery root, eggplant, parsley root, parsnip and potato were used as reagents, hydrolysis of the acetates was successful. At low conversion the hydrolysis was stereoselective and at total conversion virtually no formation of by-products was observed. The selectivity varied among the eight vegetables that were evaluated. Methods of preparation and substrate-to-plant ratio were examined. Furthermore, acetates and benzoates of three analogous compounds [5-hydroxy-3-heptanone (2), 5-hydroxy-5-methyl-3-heptanone (3) and 5-ethyl-6-hydroxy-4-octanone (4)] were hydrolyzed by potato and sweet potato to various degrees, indicating that the method is general for the mild and stereoselective hydrolysis of secondary beta-alkoxy-and beta-aryloxyketones.

A facile one-pot synthesis providing vicinal diols and 1,3-diols in >95% stereoisomeric purity from commercially available enantiopure hydroxy esters has been developed. The esters were reduced with DIBALH and alkylated in situ with 4-pentenylmagnesium bromide, which after workup generated the title diols as diastereomeric pairs. These pairs were easily separated by preparative chromatography, affording products with retained stereoisomeric purity from the starting materials. This method represents an expedient preparation of many common natural products, such as cerambycid beetle pheromones and intermediates towards bicyclic acetal bark beetle pheromones. (C) 2016 Elsevier Ltd. All rights reserved.

Volatiles from the metastemal glands of two species Of true bugs of the Triatominae subfamily, Triatoma brasiliensis and Triatoma infestans, Were analyzed by SPME-GC/MS. Two sets of new natural products were found: (4S,5S)- and (4R,SR)-2,2,4-triethyl-5-methyl-1,3-dioxolane (1) (major component) and (45*,5S*)-2,4-diethyl-2,S-dimethyl-1,3-dioxolane (2) (trace component),-,(2R/S,4S,SS)- as well as (2R/S,4R,5R)-4-ethyl-5-methyl-2-(1-methylethyl)-1,3-dioxolane (3) (minor component), (2R/S,4S*,5S*).-4-ethyl-5-methyl-2-(1-methylpropyl)-1,3-dioxolane (4), (trace component), and (2R/S,4S*,5S*)-4-ethyl-5-methyl-2-(2-methylpropyl)-1,3-dioxolane (5) (trace component). Syntheses of optically active 1 and 3 were carried out by reacting pure,enantiomers of 2,3-pentanediol with 3-pentanone or 2-methylpropanal. The preparation of, pure 1 stereoisomers of 2,3-pentanediol involved a novel key step for the synthesis of secondary alcohols: the reduction of a carboxylic ester by means of DIBAH and in situ alkylation of the intermediate by Grignard reaction at low temperature Starting from the pure enantiomers of methyl lactate; all four stereoisoniers of 2,3-pentanediol were synthesized. and transformed, to the corresponding isomers of 1 and 2. Relative configurations of the natural products and enantiomeric compositions of naturally occurring 1 and :2 were determined by comparison of their mass spectra and gas chromatographic retention times (co-injection) I with those of authentic reference samples.

All four possible stereoisomers of 5-hydroxy-4-methyl-3-heptanone were synthesized from common achiral reagents using fast, straightforward organic synthesis, including the use of whole tissue of Daucus carota, Solanum melongena, and Pleurotus ostreatus.

Background: The triatomine bug Rhodnius prolixus Stal, 1859 (Heteroptera: Reduviidae) is the primary vector of Chagas disease in Colombia and Venezuela. An important step in controlling Chagas disease is monitoring the growth and spread of bug populations to inform effective management. Such monitoring could be carried out using pheromone traps. To develop effective pheromone traps, it is vital to understand the pheromone chemistry of R. prolixus. Previous studies have found that female R. prolixus metasternal gland secretions induce males to: leave shelters, take off, orientate during walking, aggregate around mating pairs, and mate. This study aims to identify a synthetic blend of female metasternal gland compounds that could be used to attract R. prolixus. Results: We investigated the electrophysiological activity of the ten most abundant compounds in female R. prolixus metasternal glands using single sensillum recordings. In total we obtained 60 recordings from basiconic sensilla in male R. prolixus. In 31 of these recordings, responses to individual compounds were observed. Each of the ten tested compounds elicited neuron responses in a minimum of eight recordings. Having confirmed their electrophysiological activity, we tested these ten compounds by presenting them to male Rhodnius prolixus in a 7 olfactometer. Male bugs showed a significant preference for the blend of metasternal gland compounds compared to the clean air control. Conclusions: A simple blend of ten compounds found in female R. prolixus metasternal glands is attractive to conspecific males. All compounds in the blend are either commercially available at low cost, or easily synthetically prepared from simple precursors. We hope that this blend will be evaluated as a lure for pheromone traps in field bioassays.

The floral fragrance of the shrub Daphne mezereum in central Sweden was collected by means of the head-space technique and investigated by GC-MS and multi-dimensional GC. (S)-(+)-Linalool was the main constituent (95%) of the flower fragrance and its enantiomeric purity exceeded 99% in the samples. The (2S, 5S)- and (2R, 5S)-furanoid and the (3R, 6S)- and (3S, 6S)-pyranoid linalool oxide isomers constituted 2-5% of the fragrance. The elution order of these compounds on a permethylated beta-cyclodextrin column is reported. A fragrance sample of D. mezereum as well as (S)-(+)-linalool attracted males of the vernal solitary bee species Colletes cunicalarius and Andrena cinerea. A racemic mixture of the two enantiomeric pairs of known furanoid linalool oxides was only weakly attractive to the bees. The role of the fragrance in the pollination specialization of the plant is discussed.

The odour released from the flower of the voodoo lily Sauromatum guttatum Araceae and the odour of the mushroom Phallus impudicus Phallaceae were analysed. The two species had the major constituents dimethyl disulphide and dimethyl trisulphide in common. Other major components of the S. guttatum excretion were beta caryophyllene, dimethyl sulphide, dimethyl tetrasulphide, indole and skatole. Linalool, trans-ocimene, and phenylacetaldehyde were released by P. impudicus.

Vespula wasps are widely distributed invasive alien species that are able to reach high population densities in the 1.2 M ha of beech forests (Fuscospora spp.) of New Zealand's South Island. These endemic temperate forests have an abundance of carbohydrate-rich honeydew produced by native scale insects (Ultracoelostoma spp.). A characteristic aroma is associated with the honeydew in beech forests, which we hypothesized is the signal used by wasps to harvest the vast resources previously exploited by birds and other insects. Volatile collections were taken of black beech tree trunks with honeydew and sooty mold present, and analyzed with a gas chromatograph-mass spectrometer. Eleven compounds (benzaldehyde, benzyl alcohol, 2-phenylethyl acetate, 2-phenylethanol, phenylacetaldehyde, methyl 2-phenylacetate, ethyl 2-phenylacetate, methyl salicylate, n-octanol, octan-3-ol, and 1-octen-3-ol) were positively identified from the headspace, and were shown to elicit an electrophysiological response from Vespula vulgaris worker antennae by using electroantennography (EAG). Field trials with delta traps individually baited with these compounds confirmed wasp attraction to 8 of the 11 compounds tested, with 2-phenylethyl acetate, methyl salicylate, and octan-3-ol capturing the same numbers of wasps as the control. In later trials, attraction to a 1:1 blend of benzaldehyde and n-octanol was significantly higher (45 %) than to any other treatment. Many of the chemicals identified are known to be associated with fermenting sugars, or with fungal aroma. Benzaldehyde and n-octanol are common compounds produced by many different species in nature. The ability to respond to generic signals emanating from sugar resources is likely to contribute to the success of V. vulgaris as an invasive species.

The introduction of invasive social wasp species of the genus Vespula (Hymenoptera: Vespidae) to New Zealand has caused a major ecological problem, particularly in the beech forests (Nothofagus spp.) of the South Island, where they have destabilized the native bird and invertebrate biodiversity. New attractants are under investigation as part of a search for pest management solutions. Fermenting brown sugar has been previously reported as a social wasp attractant. This work was undertaken to identify compounds from fermented brown sugar attractive to social wasps. Raw fermented brown sugar was confirmed to be attractive in a field trial and 10 chemical compounds present in the headspace were positively identified by coupled gas chromatography-mass spectrometry and synthetic references. During electroantennogram experiments, 3-methyl-1-butanol, 3-methylbutyl acetate, and ethyl hexanoate elicited high electrophysiological responses from Vespula vulgaris (L.) antennae. These compounds mediated attraction of V.vulgaris wasps in forest margins by trapping. A blend of these compounds could be used as a lure in a monitoring tool, or even a local suppression method if combined with a toxin.

Single sensillum recordings from Cydia pomonella male antennae showed three different types of receptor neurons. The most abundant type was most sensitive to the main pheromone compound (E,E)-8,10-dodecadienol, while its response to the geometric isomers E,Z, Z,E and Z,Z was comparable to a tenfold lower dose of (E,E)-8,10-dodecadienol. This neuron type also responded to the four behaviorally antagonistic isomers of (Delta,Delta)-8,10-dodecadienyl acetate, among which it was most sensitive to the E,E isomer. Cross-adaptation studies showed that these compounds were all detected by the same receptor neuron type. Receptor neurons specifically tuned to (E,Z) or (Z,Z)-8,10-dodecadienol were not found, although these two compounds are behaviorally active. A second type of receptor neuron responded to all isomers of (Delta,Delta)-8,10-dodecadienyl acetate and was most sensitive to the E,E isomer. This neuron type did not respond to any of the isomers of (Delta,Delta)-8,10-dodecadienol. A third receptor neuron type was highly sensitive to the plant compound alpha-farnesene. The finding that the receptor neuron type tuned to the main pheromone compound responded even to strong behavioral antagonists aids the interpretation of ongoing behavioral studies for the development of the mating disruption technique in codling moth.

Virgin female gland extracts of sugarcane moth Diatraea saccharalis (Fabricius) (Lepidoptera: Pyralidae), from three locations in Brazil, have been analyzed. By GC-MS analysis and comparison of the chromatographic retention time of the components of the pheromone gland with those retention times of synthetic standards, we observed the presence of (Z)-hexadec-11-enal (1), hexadecanal (2), (9E,11E)-hexadecadienal (4), (9Z,11Z)-hexadecadienal (5) and (9E,11E)-hexadecadienal (6), as minor components besides the major constituent (9Z,11E)-hexadecadienal (3) already reported. We found no variations in the composition of the gland extracts deriving from the three Brazilian populations and only two compounds, (Z)-hexadec-11-enal (1) and (9Z,11E)-hexadecadienal (3), elicited antennal responses (GC-EAD). In electroantennography (EAG), however, pure compounds 1 and 3, a binary mixture containing 1 and 3, and a mixture containing all of the six synthetic compounds 1-6 elicited a depolarization in male antennae of D. saccharalis, without any statistically different delay. The EAG responses to the other isomers of 9,11-hexadecadienal were small and not significantly different from the control, except for the (9Z,11Z)-isomer (5) which showed an relatively strong electroantennal activity.

The female sex pheromone of Bonagota (=Phthteochroa) cranaodes (Meyrick) is a blend of (E,Z)-3,5-dodecadienyl acetate (E3,Z5-12:Ac) and (Z)-9-hexadecenyl acetate (Z9-16:Ac) according to analysis of pheromone - gland extracts and field trapping in apple orchards. This is the first time that E3,Z5-12:Ac has been identified as a lepidopteran sex pheromone. Traps baited with 100 mu g E3,Z5-12:Ac were attractive over 15 weeks in the field and were as effective as traps baited with virgin females. Addition of Z9-16:Ac to E3,Z5-12:Ac at ratio of 1:10 had a significantly increase of male moths. The addition of the Z,E and Z:Z isomers to rubber septa baited with E3,Z5-12:Ac did not modify B. cranaodes male attraction, but 10% of EE enhanced trap catch.

The total and relative amounts of (Z)-11-tetradecenyl acetate (Z11-14:Ac), (E)-11-tetradecenyl acetate (E11-14:Ac), (Z)-11-tetradecen-1-ol (Z11-14:OH) and (Z)-11-tetradecenal (Z11-14:Al), and the EAG response of male antennae to these pheromone gland compounds were compared in laboratory reared Choristoneura rosaceana Harris (Lepidoptera: Tortricidae) from British Columbia, Michigan, Ontario, New York, and Quebec. A field trapping experiment was conducted in each of these locations to determine the effect of Z11-14:Al on the numbers of moths captured. The amount of each of the four pheromone-gland compounds declined successively in moths from British Columbia, Quebec, Ontario, Michigan, and New York. The relative amount of Z11-14:Ac was greatest in moths from New York and smallest in moths from Ontario, whereas the relative amount of E11-14:Ac was greatest in moths from Ontario and smallest in moths from British Columbia. Moths from Ontario, Quebec, British Columbia, Michigan, and New York contained decreasing relative amounts of Z11-14:OH and Z11-14:Al. There was a trend of increasing antenna] sensitivity to each of the four pheromone-gland compounds in moths from New York, Michigan, Ontario, Quebec, and British Columbia. The addition of 1% Z11:Al to a three compound blend of Z11-14:Ac, E11-14:Ac and Z11-14:OH (97:2:1) resulted in a >twofold increase in average trap catch in British Columbia, Ontario, and Quebec; this compound had no effect on trap catch in Michigan or New York.

The antennae of male spotted tentiform leafminers, Phyllonorycter blancardella, from Ontario, Canada, exhibited similar electroantennogram responses when stimulated with E10-12:Ac or E4,E10-12:Ac. In field trapping experiments, E10-12:Ac was two-fold or more attractive than E4, E10-12:Ac, and E4,E10-12:Ac did not enhance the attractiveness of E10-12:Ac. E4,E10-12:Ac has not been identified in the pheromone of P. blancardella and it is hypothesized that the structural similarity of this compound and E10-12:Ac, the major pheromone compound of this species, may be responsible for the electrophysiological and behavioral responses to E4,E10-12:Ac. The possible reasons for the disparity between the results of our field trapping experiments and those carried out in Nova Scotia, Canada, and Massachusetts, USA., where E4,E10-12:Ac was found to be two to four times more attractive to P. blancardella than E10-12:Ac, are discussed.

We studied the effect of codlemone geometric isomers (E,Z)-, (Z,E)-, and (Z,Z)-8,10-dodecadienol on sex attraction of male codling moth, Cydia pomonella (L.), in the field and in a wind tunnel. The use of an ultrasound evaporator made it possible to apply known rates of compound at defined isomeric purity. In the wind tunnel, 5, 20, and 100% addition of Z,E isomer to (E,E) -8,10-dodecadienol (codlemone) slightly increased male night response. However, field captures with these blends were not significantly different from codlemone alone. A 20 and 100% addition of E,Z isomer decreased male landings on the odor source in the wind tunnel and trap captures in the field; Z,Z had an antagonistic effect at 100%. The equilibrium isomer blend (100% EB; 26% E,Z; 20% Z,E; 5% Z,Z) strongly reduced male attraction. The behavioral effect of isomerization of codlemone in dispenser materials used for mating disruption has to be taken into consideration.

In a previous study we have reported that both (E,Z)-8,10-dodecadienol (E,Z) and (Z,Z) 8,10-dodecadienol (Z,Z) isomers inhibit the attraction of male codling moth, Cydia pomonella L. when added to (E,E)-8,10-dodecadienol (E,E) while the (Z,E)-8,10-dodecadienol (Z,E) isomer induces slight increase in the number of males attracted to the pheromone source. In the present study, we have tested the behavioral activity of the individual geometrical isomers E,Z; Z,E and Z,Z. A few number of codling moth males flew to the Z,E-isomer while the other two isomers (i.e. E,Z and Z,Z) did not elicit any upwind orientation. Analysis of the Right behavior to the E,E- and Z,E-isomer showed significant differences in most of the flight parameters evaluated. Based on the biological observations and molecular modeling, we suggest that the behavioral activity of the Z,E-isomer is due to presence of specific receptors for this isomer on male antennae and not to its structural resemblance to the E,E-isomer. These results underline the importance of the Z,E-isomer in sex attraction of male codling moth.

Since of the first sex pheromone and the adoption of pheromone in pest management, the global pheromone market size has grown to reach USD 2.4 billion per year in 2019. This has enabled the development of environmentally friendly approaches that significantly reduce the application of pesticides. Recently, there have been reports of the failure of various commercial codlemone: (E,E)-8,10-dodecadien-1-ol formulations used for monitoring the apple pest codling moth, Cydia pomonella (L.). This work was initiated to investigate factors behind the lack of efficacy of codlemone lure in the Northern Hemisphere (Germany) and Southern Hemisphere (New Zealand). We hypothesised that the observed failure could be due to two main factors: (a) a shift in the response of male codling moth to codlemone and (b) degradation of codlemone under field conditions that renders the lure less attractive. Field trial tests of various doses and blends containing minor pheromone compounds suggested no change in response of male codling moth. The addition of an antioxidant and a UV stabiliser to codlemone resulted in a significant increase in the number of males caught in Germany, but not in New Zealand. Mean maximum temperatures during the growing season since 2004 indicate a 3 degrees C increase to 35 degrees C in Germany, but just a 1.5 degrees C rise to 30 degrees C in New Zealand. Chemical analysis of the lures used in the field trials in Germany and New Zealand indicated more degradation products and reduced half-life of the lures in Germany compared with those in New Zealand. Heating codlemone lures to 32 degrees C significantly reduced the number of males caught in traps and increased the isomeric and chemical impurities of codlemone compared with unheated lures. Our data provide the first evidence that climate change affects pheromone molecule stability, thus reducing its biological efficacy. Our finding suggests that climate change could be a general problem for chemical communication and, therefore, could affect the integrity of natural ecosystems.

Plants release volatiles in response to caterpillar feeding.These herbivore-induced plant volatiles (HIPVs) attract natural enemies of the herbivores and repel or attract conspecific adult herbivores in a tri-trophic interaction which has been considered to be an indirect plant defense against herbivores. Recently, we demonstrated the attraction of male and female European grapevine moth, Lobesia botrana (Denis & Schiffermuller) (Lepidoptera: Tortricidae) to a blend of phenylacetonitrile and acetic acid, two compounds identified as HIPVs in heterospecific apple-leafroller interactions. The ecological basis of our findings is not clearly understood.Thus, this work was undertaken to investigate HIPVs in the grapevine-leafroller interaction and study the response of heterospecific adults L. botrana, to these volatiles. We collected headspace volatiles emitted from uninfested grapevines and grapevines infested with larvae of a generalist herbivore, the grapevine leafroller moth, Sparganothis pilleriana (Denis & Schiffermuller), and analyzed them using gas chromatography/mass spectrometry. Infested grape leaves released three compounds (phenylacetonitrile, indole, and 2-phenylethanol) not found from uninfested leaves. Nine different blends, comprising a full factorial set of the three oompou nds with each blend containing acetic acid, were tested in a field-cage trial. Only lures containing phenylacetonitrile caused a significant increase in trap catches compared to the other lures and blank traps. Electroantennographic tests show that L botrana can detect the compounds. The results confirm our hypothesis that phenylacetonitrile is released during grapevines infestation with herbivores, and attracts adult L. botrana.

Three varieties of honey of different dominant floral origin were found to attract social Hymenoptera, including the large earth bumble bee, Bombus terrestris, in a New Zealand mountain beech forest. This study was undertaken to identify volatile organic compounds that induce the attraction of bumble bees to honeybee (Apis mellifera) honey. We analyzed the chemical composition of the volatile organic compounds produced in three distinct varieties of honey (i.e., manuka, honeydew, and clover honey). The composition of the chemical profile of the three honey varieties differed in the quality and in the ratio of compounds in the headspace. o-Methoxyacetophenone was the main compound in the headspace of all three honey varieties. Among the 40 compounds identified in the headspace in the three varieties, only seven shared compounds (i.e., benzaldehyde, benzyl alcohol, phenylacetaldehyde, 2-phenylethanol, isophorone, 4-oxoisophorone, and o-methoxyacetophenone) were present in the headspace of the three honey varieties. The relative attractiveness of various blends of the seven common compounds found in the three honey varieties was tested for the attraction to bumble bees in a mountain beech forest. A binary blend of isophorone and 4-oxoisophorone at a ratio of 90:10 was the most attractive blend for both bumble bee workers and queens. A small number of honey bee workers were also attracted to the former binary blend. Our study represents the first identification of a honey-derived attractant for bumble bees and honey bees. The potential application of our finding for monitoring of bumble bees or to enhance crop pollination and help to tackle the current concern of a global pollination crisis is discussed.

The composition of the rectal gland secretion and volatiles emitted by female Queensland fruit fly, Bactrocera tryoni was investigated. Esters were found to be the main compounds in the gland extracts and headspace, while amides were the minor compounds in the gland extracts and headspace. Ethyl dodecanoate, ethyl tetradecanoate, ethyl (Z9)-hexadecenoate and ethyl palmitate were the main esters in the gland extracts, while ethyl dodecanoate and ethyl tetradecanoate were the main esters in the headspace. Four amides (N-(3-methylbutyl)acetamide), N-(2-methylbutyl)propanamide, N-(3-methylbutyl)propanamide, and N-(3-methylbutyl)-2-methylpropanamide were found in the gland extracts and the headspace. Among the amides, N-(3-methylbutyl)acetamide and N-(3-methylbutyl)propanamide were the main amides in the gland extracts and the headspace.Traces of three spiroacetals were found both in the gland extracts and in the headspace. (E,E)-2,8-Dimethyl-1,7-dioxaspiro[5.5]undecane, (E,E)-2-ethyl-8-methyl-1,7-dioxaspiro[5.5]undecane, (E,E)-2-propyl-8-methyl-1,7-dioxaspiro[5.5]undecane. All compounds found in the headspace were present in the extract of the rectal gland suggesting that the rectal gland is the main source of the headspace volatiles, whose function remains to be elucidated.This is the first comprehensive chemical analysis of the rectal gland secretions and volatiles of female B. tryoni, and further laboratory and field bioassays are required to determine the function of compounds identified in this study. Discovery of the same amides previously identified in the male rectal gland in the female rectal gland raises questions about the pheromonal role previously suggested for these compounds.

BACKGROUND: The common wasp, Vespula vulgaris (L.), and the German wasp, Vespula germanica (F.), are significant problems in New Zealand beech forests (Nothofagus spp.), adversely affecting native birds and invertebrate biodiversity. This work was undertaken to develop synthetic attractants for these species to enable more efficient monitoring and management. RESULTS: Seven known wasp attractants (acetic acid, butyl butyrate, isobutanol, heptyl butyrate, octyl butyrate and 2,4-hexadienyl butyrate) were field tested, and only heptyl butyrate and octyl butyrate attracted significantly higher numbers of wasps than a non-baited trap. Accordingly, a series of straight-chain esters from methyl to decyl butyrate were prepared and field tested for attraction of social wasps. Peak biological activity occurred with hexyl butyrate, heptyl butyrate, octyl butyrate and nonyl butyrate. Polyethylene bags emitting approximately 18.4-22.6 mg day(-1) of heptyl butyrate were more attractive than polyethylene bags emitting approximately 14.7-16.8 mg day(-1) of heptyl butyrate in the field. Electroantennogram (EAG) studies indicated that queens and workers of V. vulgaris had olfactory receptor neurons responding to various aliphatic butyrates. CONCLUSION: These results are the first to be reported on the EAG response and the attraction of social wasps to synthetic chemicals in New Zealand beech forests and will enable monitoring of social wasp activity in beech forests. (C) 2009 Society of Chemical industry

Headspace volatiles collected from virgin females of the citrophilous mealybug, Pseudococcus calceolariae, contain three Compounds not present in the headspace of control samples. The main female-specific compound is identified as[2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropyl]methyl 2-acetoxy-3-methylbutanoate (chrysanthemyl 2-acetoxy-3-methylbutanoate). The other two compounds are identified as [2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropyl]methanol (chrysanthemol) and [2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropyl]methyl 2-hydroxy-3-methylbutanoate (chrysanthemyl 2-hydroxy-3-methylbutanoate). Traps baited with 100 mu g and 1000 mu g of chrysanthemyl 2-acetoxy-3-methylbutanoate captured 4- and 20-fold more males than traps baited with virgin females.

Rhodnius prolixus is one of the most important vectors of Chagas disease in Central and South America for which repellents and attractants are sorely needed. Repellents like DEET, picaridin, and IR3535 are widely used as the first line of defense against mosquitoes and other vectors, but they are ineffective against R. prolixus. Our initial goal was to identify in R. prolixus genome odorant receptors sensitive to putative sex pheromones. We compared gene expression of 21 ORs in the R. prolixus genome, identified 4 ORs enriched in male (compared with female) antennae. Attempts to de-orphanize these ORs using the Xenopus oocyte recording system showed that none of them responded to putative sex pheromone constituents. One of the them, RproOR80, was sensitive to 4 compounds in our panel of 109 odorants, namely, 2-heptanone, gamma-octalactone, acetophenone, and 4-methylcychohexanol. Interestingly, these compounds, particularly 4-methylcyclohexanol, showed strong repellency activity as indicated not only by a significant decrease in residence time close to a host, but also by a remarkable reduction in blood intake. 4-Methylcyclohexanol-elicited repellency activity was abolished in RNAi-treated insects. In summary, our search for pheromone receptors led to the discovery of repellents for R. prolixus.

Herein we report the asymmetric syntheses of a number of oxygenated terpenoids that are of importance in the chemical ecology of bark beetles. These are pinocamphones, isopinocamphones, pinocarvones, and 4-thujanols (= sabinene hydrates). The camphones were synthesized from isopinocampheol, the pinocarvones from beta-pinene, and the thujanols from sabinene. The NMR spectroscopic data, specific rotations, and elution orders of their stereoisomers on a chiral GC-phase (beta-cyclodextrin) are also reported. This enables facile synthesis of pure compounds for biological activity studies and identification of stereoisomers in mixed natural samples.

The search for mates and food is mediated by volatile chemicals. Insects sense food odorants and sex pheromones through odorant receptors (ORs) and pheromone receptors (PRs), which are expressed in olfactory sensory neurons. Molecular phylogenetics of ORs, informed by behavioral and functional data, generates sound hypotheses for the identification of semiochemicals driving olfactory behavior. Studying orthologous receptors and their ligands across taxa affords insights into the role of chemical communication in reproductive isolation and phylogenetic divergence. The female sex pheromone of green budworm mothHedya nubiferana(Lepidoptera, Totricidae) is a blend of two unsaturated acetates, only a blend of both elicits male attraction. Females produce in addition codlemone, which is the sex pheromone of another tortricid, codling mothCydia pomonella. Codlemone also attracts green budworm moth males. Concomitantly, green budworm and codling moth males are attracted to the host plant volatile pear ester. A congruent behavioral response to the same pheromone and plant volatile in two tortricid species suggests co-occurrence of dedicated olfactory channels. In codling moth, one PR is tuned to both compounds, the sex pheromone codlemone and the plant volatile pear ester. Our phylogenetic analysis finds that green budworm moth expresses an orthologous PR gene. Shared ancestry, and high levels of amino acid identity and sequence similarity, in codling and green budworm moth PRs offer an explanation for parallel attraction of both species to the same compounds. A conserved olfactory channel for a sex pheromone and a host plant volatile substantiates the alliance of social and habitat signals in insect chemical communication. Field attraction assays confirm that in silico investigations of ORs afford powerful predictions for an efficient identification of behavior-modifying semiochemicals, for an improved understanding of the mechanisms of host plant attraction in insect herbivores and for the further development of sustainable insect control.

BACKGROUNDEndemic New Zealand grass grub Costelytra zealandica is a pest of introduced pasture that uses phenol as a sex pheromone. The pheromone could be used to monitor and manage grass grub populations, but the irritating properties and toxicity of phenol for human handlers, as well as the possible ecotoxicological effects, pose obstacles to the deployment of the pheromone. This study aimed to limit the use of phenol by dose-response studies and investigation into alternative attractants and synergists to phenol. RESULTSNo difference in trap catch was seen across the range of 1-100mg of phenol, while rates below this (0.001-0.1mg) caused a large drop in catches. Our results indicated that 1mg loading in lures was enough to indicate beetle presence over 1 week. 4-Hydroxybenzaldehyde and p-cresol proved unattractive in this study, both as single attractants and as synergists with phenol. Phenyl acetate, phenyl benzoate and diphenyl carbonate all formed phenol under hydrolytic conditions to act as successful propheromones, while phenyl acetate was found to be as attractive as phenol on its own. CONCLUSIONThis study described several ways to reduce or avoid the use of phenol in the field while maintaining lure effectiveness. (c) 2017 Society of Chemical Industry

Herein we report on the development and application of chemoenzymatic Dynamic Kinetic Asymmetric Transformation (DYKAT) of alpha-substituted beta-hydroxketones (beta-HKs), using Candida antartica lipase B (CALB) as transesterification catalyst and a ruthenium complex as epimerization catalyst. An operationally simple protocol allows for an efficient preparation of highly enantiomerically enriched alpha-substituted beta-oxoacetates. The products were obtained in yields up to 95% with good diastereomeric ratios.

Insects detect odors using an array of odorant receptors (ORs), which may expand through gene duplication. How and which new functions may evolve among related ORs within a species remain poorly investigated. We addressed this question by functionally characterizing ORs from the Eurasian spruce bark beetle Ips typographus, in which physiological and behavioral responses to pheromones, volatiles from host and nonhost trees, and fungal symbionts are well described. In contrast, knowledge of OR function is restricted to two receptors detecting the pheromone compounds (S)-(-)-ipsenol (ItypOR46) and (R)-(-)-ipsdienol (ItypOR49). These receptors belong to an Ips-specific OR-lineage comprising seven ItypORs. To gain insight into the functional evolution of related ORs, we characterized the five remaining ORs in this Glade using Xenopus oocytes. Two receptors responded primarily to the host tree monoterpenes (+)-3-carene (ItypOR25) and p-cymene (ItypOR27). Two receptors responded to oxygenated monoterpenoids produced in larger relative amounts by the beetle-associated fungi, with ItypOR23 specific for (+)-trans-(1R, 4S)-4-thujanol, and ItypOR29 responding to (+)-isopinocamphone and similar ketones. ItypOR28 responded to the pheromone E-myrcenol from the competitor Ips duplicatus. Overall, the OR responses match well with those of previously characterized olfactory sensory neuron classes except that neurons detecting E-myrcenol have not been identified. The characterized ORs are under strong purifying selection and demonstrate a shared functional property in that they all primarily respond to monoterpenoids. The variation in functional groups among OR ligands and their diverse ecological origins suggest that neofunctionalization has occurred early in the evolution of this OR-lineage following gene duplication.

BACKGROUND Eurasian spruce bark beetles (Ips typographus) use both attractant and anti-attractant semiochemicals to find suitable mature host trees. Trans-4-thujanol is abundant in young, unsuitable spruce trees. Electrophysiological studies have demonstrated its high activity levels, but field data are lacking. RESULTS Enantioselective GC-MS analysis showed that only (1R,4S)-(+)-trans-4-thujanol was present in Norway spruce bark volatiles. In a factorial design field-trapping experiment, trans-4-thujanol alone was not attractive to Ips typographus. Traps baited with I. typographus' aggregation pheromone and trans-4-thujanol or the known anti-attractant 1,8-cineole caught fewer beetles than those baited with the aggregation pheromone alone. Catches for trans-4-thujanol and 1,8-cineole were dose-dependent. Intermediate doses of trans-4-thujanol and 1,8-cineole had a similar effect. Surprisingly, in contrast to 1,8-cineole and other known Ips anti-attractants, which all inhibit males more strongly than females, the addition of trans-4-thujanol to the aggregation pheromone reduced the attraction of females more. CONCLUSION The Norway spruce volatile (+)-trans-4-thujanol is a novel I. typographus anti-attractant with potency comparable to the known anti-attractants 1,8-cineole and verbenone, and is more effective for females than for males. Incorporating (+)-trans-4-thujanol into anti-attractant lures could improve protection of trees from mass attack by I. typographus.

The ability of olfactory receptor neurons to detect female-produced sex pheromone components and a limited sample of potential host plant odours was studied by single-sensillum recordings from olfactory sensilla present on male and female antennae in Manduca sexta, The majority of pheromone-sensitive receptor neurons examined in males was specialized for detection of the two major pheromone components, E10,Z12-hexadecadienal and E10,E12,Z14-hexadecatrienal or E10,E12,E14-hexadecatrienal. New olfactory receptor neurons tuned to the minor components E10,E12-hexadecadienal and Z11-hexadecenal were found. in females, olfactory receptor neurons specific to Z11-hexadecanal were discovered. Pheromone components and host volatiles were detected by separate sets of receptor neurons.

(+)-Limonene (d-limonene) and related monoterpenes show chemopreventive activity against rodent mammary carcinoma and inhibit the growth of cancer cells in vitro, One suggested mechanism for the anti-tumorigenic effect of (+)-limonene is inhibition of the post-translational isoprenylation of growth controlling Pas oncoproteins. We have here examined the growth inhibitory effects of (+)-limonene and other related monoterpenes on PANC-1 pancreas carcinoma cells (carrying a K-ras mutation) and on 12V-H-ras-transformed rat fibroblasts, (+)- and (-)-perillyl alcohol, 7-methyl-perillyl alcohol, (+)-limonene oxide and (+)-perillic acid methyl ester were all found to efficiently inhibit cell growth at 1 mM, whereas (+)-limonene caused an approximately 50% growth reduction at 5 mM, Whereas BZA-BB, an inhibitor of Ras farnesyl transferase, was found to induce morphological reversion of 12v-H-ras-transformed cells, (+)-perillyl alcohol and (+)-limonene did not induce reversion. Furthermore, monoterpenes did not decrease MAP kinase enzyme activity or collagenase promoter activity in PANC-1 cells, two functions known to be down-stream from Pas, We conclude that although effective in inhibiting the growth of tumor cells harboring activated res oncogenes, limonene and (+)-perillyl alcohol are unlikely to act by inhibiting Ras function.

Laboratory screening bioassays and field trapping experiments of spotted wing drosophila flies, Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), were conducted to determine the attractiveness of 17 compounds as well as to compare attractant efficiency during peak fruit ripeness and postharvest captures late in the season. Compounds structurally related to each of the fermentation products acetic acid, ethanol, ethyl acetate, and 2-phenethyl alcohol were screened for attractiveness compared with a soap water control in greenhouse cage bioassays. The compounds determined to be attractive in the greenhouse bioassay (methanol, ethanol, propanol, formic acid, acetic acid, ethyl acetate, propyl acetate, phenethyl acetate, phenethyl propionate, and phenethyl butyrate) were individually tested in the field added to apple cider vinegar (ACV). The acids were also tested individually in neutralized AVC (NACV; pH 7). Combinations of the compounds were tested in NACV. The capture numbers in ACV traps were not significantly increased by the addition of any of the compounds tested, although significant deterrent effects of some of the compoundsallowed differences between treatments to be observed. Compounds that are most prevalent in wine and vinegar (methanol, ethanol, acetic acid, and ethyl acetate) as well as phenethyl propionate and phenethyl butyrate were less deterrent than the other compounds tested in the field. Captures during peak fruit ripeness were compared with the postharvest period when fruit hosts were not available or were overripe. Although the total number of flies captured late in the season was lower, the trends in treatment performance were similar, indicating a consistent performance of these baits from peak fruit ripeness through postharvest.

The pine weevil Hylobius abietis (L.) (Coleoptera: Curculionidae) feeds on the bark of coniferous seedlings and is the economically most important forestry restocking pest in large parts of Europe. Substances with an antifeedant effect may offer an environmentally friendly alternative to insecticides for the protection of planted seedlings. Bioassays were performed on commercial and synthetic methyl hydroxy-methoxybenzoates in order to determine their possible antifeedant activity. Two methyl hydroxy-methoxybenzoates were synthesized by esterification and mono-O-methylation of two dihydroxybenzoic acids. A regioselective protection-deprotection strategy was used in the synthetic pathway of the other non-commercial esters, esterification and selective pivaloylation of the less-hindered hydroxyl group of other commercial dihydroxybenzoic acids gave diester intermediates, which then were O-methylated before methanolysis of the pivaloyl group which yielded the desired non-commercial methyl hydroxy-methoxybenzoates. The five synthesized methyl hydroxy-methoxybenzoic esters were complemented with commercial samples of the five other isomers of methyl hydroxy-methoxybenzoate and spectrometric data were collected for the complete set of isomers. All ten isomers were tested for their antifeedant effect on the pine weevil. The effect varied considerably among the hydroxy-methoxybenzoic esters. Methyl 2-hydroxy-3-methoxybenzoate showed the highest effect and may thus be a candidate for practical use in pine weevil pest management.

Female pheromone glands of the leafroller Argyrotaenia sphaleropa were analyzed. Two acetates were identified as (11Z,13)-tetradecadien-1-yl acetate and (11Z)-tetradecen-1-yl acetate by comparison with synthesized references. The (11Z,13)-tetradecadien-1-yl acetate and the aldehyde (11Z,13)-tetradecadienal were synthesized via a Wittig reaction. A field-trapping test showed that a lure consisting of a mixture of (11Z 13)-tetradecadienal and (11Z,13)tetradecadien-1-yl acetate in a 10:1-ratio produced the highest trap catches.

The preparation, characterization and application of a new stationary phase derived from 1,4-cyclohexanedione and diethyl (+)-tartrate are described. A suitable TADDOL for immobilization has been synthesized and grafted to a gamma-mercaptopropylsilylated silica gel. The resulting modified stationary phase has been characterized and its ability to separate enantiomers has been studied. While the free TADDOL in solution was able to resolve a range of enantiomers, the resolving properties were lost on immobilization. Solid state C-13 CPMAS NMR of the new stationary phase was used to explain the lack of stereoselective recognition. (C) 2010 Elsevier Ltd. All rights reserved.