- Electrophysiological responses of bactrocera kraussi (Hardy) (tephritidae) to rectal gland secretions and headspace volatiles emitted by conspecific males and females
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Pheromones are biologically important in fruit fly mating systems, and also have potential applications as attractants or mating disrupters for pest management. Bactrocera kraussi (Hardy) (Diptera: Tephritidae) is a polyphagous pest fruit fly for which the chemical profile of rectal glands is available for males but not for females. There have been no studies of the volatile emissions of either sex or of electrophysiological responses to these compounds. The present study (i) establishes the chemical profiles of rectal gland contents and volatiles emitted by both sexes of B. kraussi by gas chromatography–mass spectrometry (GC–MS) and (ii) evaluates the detection of the identified compounds by gas chromatography–electroantennogram detection (GC–EAD) and –electropalpogram detection (GC–EPD). Sixteen compounds are identified in the rectal glands of male B. kraussi and 29 compounds are identified in the rectal glands of females. Of these compounds, 5 were detected in the headspace of males and 13 were detected in the headspace of females. GC–EPD assays recorded strong signals in both sexes against (E,E)-2,8-dimethyl-1,7-dioxaspiro[5.5]undecane, 2-ethyl-7-mehtyl-1,6-dioxaspiro[4.5]decane isomer 2, (E,Z)/(Z,E)-2,8-dimethyl-1,7-dioxaspiro[5.5]undecane, and (Z,Z)-2,8-dimethyl-1,7-dioxaspiro[5.5]undecane. Male antennae responded to (E,E)-2,8-dimethyl-1,7-dioxaspiro[5.5]undecane, 2-methyl-6-pentyl-3,4-dihydro-2H-pyran, 6-hexyl-2-methyl-3,4-dihydro-2H-pyran, 6-oxononan-1-ol, ethyl dodecanoate, ethyl tetradecanoate and ethyl (Z)-hexadec-9-enoate, whereas female antennae responded to (E,E)-2,8-dimethyl-1,7-dioxaspiro[5.5]undecane and 2-methyl-6-pentyl-3,4-dihydro-2H-pyran only. These compounds are candidates as pheromones mediating sexual interactions in B. kraussi.
- Holgate, Danielle,Jamie, Ian M.,Jamie, Joanne F.,Mendez, Vivian,Noushini, Sally,Park, Soo Jean,Perez, Jeanneth,Taylor, Phillip W.
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- Attraction and electrophysiological response to identified rectal gland volatiles in bactrocera frauenfeldi (schiner)
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Bactrocera frauenfeldi (Schiner) (Diptera: Tephritidae) is a polyphagous fruit fly pest species that is endemic to Papua New Guinea and has become established in several Pacific Islands and Australia. Despite its economic importance for many crops and the key role of chemical-mediated sexual communication in the reproductive biology of tephritid fruit flies, as well as the potential application of pheromones as attractants, there have been no studies investigating the identity or activity of rectal gland secretions or emission profiles of this species. The present study (1) identifies the chemical profile of volatile compounds produced in rectal glands and released by B. frauenfeldi, (2) investigates which of the volatile compounds elicit an electroantennographic or electropalpographic response, and (3) investigates the potential function of glandular emissions as mate-attracting sex pheromones. Rectal gland extracts and headspace collections from sexually mature males and females of B. frauenfeldi were analysed by gas chromatography-mass spectrometry. Male rectal glands contained (E,E)-2-ethyl-8-methyl-1,7-dioxaspiro [5.5]undecane as a major component and (E,E)-2,8-dimethyl-1,7-dioxaspiro[5.5]undecane as a moderate component. Minor components included palmitoleic acid, palmitic acid, and ethyl oleate. In contrast, female rectal glands contained (E,E)-2,8-dimethyl-1,7-dioxaspiro[5.5]undecane and ethyl laurate as major components, ethyl myristate and ethyl palmitoleate as moderate components, and 18 minor compounds including amides, esters, and spiroacetals. Although fewer compounds were detected from the headspace collections of both males and females than from the gland extractions, most of the abundant chemicals in the rectal gland extracts were also detected in the headspace collections. Gas chromatography coupled electroantennographic detection found responses to (E,E)-2,8-dimethyl-1,7-dioxaspiro[5.5]undecane from the antennae of both male and female B. frauenfeldi. Responses to (E,E)-2-ethyl-8-methyl-1,7-dioxaspiro[5.5]undecane were elicited from the antennae of females but not males. The two spiroacetals also elicited electropalpographic responses from both male and female B. frauenfeldi. Ethyl caprate and methyl laurate, found in female rectal glands, elicited responses in female antennae and palps, respectively. Y-maze bioassays showed that females were attracted to the volatiles from male rectal glands but males were not. Neither males nor females were attracted to the volatiles from female rectal glands. Our findings suggest (E,E)-2,8-dimethyl-1,7-dioxaspiro[5.5]undecane and (E,E)-2-ethyl-8-methyl-1,7-dioxaspiro[5.5]undecane as components of a sex-attracting pheromone in B. frauenfeldi.
- Alvarez, Vivian Mendez,Holgate, Danielle,Jamie, Ian,Jamie, Joanne,Jean Park, Soo,Noushini, Saeedeh,Perez, Jeanneth,Taylor, Phillip
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supporting information
(2020/03/23)
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- Catalysis of phosphorus(V)-mediated transformations: Dichlorination reactions of epoxides under appel conditions
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A stereospecific triphenylphosphine oxide-catalyzed 1,2-dichlorination reaction of epoxides has been developed. The reaction is effective for a range of terminal and internal epoxides. In contrast to the classical Appel-type dichlorination of epoxides, oxalyl chloride is used as a stoichiometric reagent to generate the chlorophosphonium salt responsible for dichlorination from catalytic triphenylphosphine oxide.
- Denton, Ross M.,Tang, Xiaoping,Przeslak, Adam
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supporting information; experimental part
p. 4678 - 4681
(2010/12/24)
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- Tailored Ru-NHC heterogeneous catalysts for alkene metathesis
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The preparation of highly active and stable Ru-NHC (ruthenium-N-heterocyclic carbene ligands) alkene metathesis catalysts through surface organometallic chemistry on hybrid mesostructured materials was reported. Two types of mesoporous hybrid materials we
- Karame, Iyad,Boualleg, Malika,Camus, Jean-Michel,Maishal, Tarun K.,Alauzun, Johan,Basset, Jean-Marie,Coperet, Christophe,Corriu, Robert J. P.,Jeanneau, Erwan,Mehdi, Ahmad,Reye, Catherine,Veyre, Laurent,Thieuleux, Chloe
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supporting information; experimental part
p. 11820 - 11823
(2010/04/28)
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- HYDROGENATION OF FATTY ACIDS ESTERS. II. KINETICS OF HYDROGENATION OF METHYL (Z)- AND (E)-9-OCTADECENOATE CATALYZED BY A ZIEGLER NICKEL CATALYST
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Kinetics of the title reactions has been studied, using nickel(II) 2,4-pentanedionate/triethylaluminium system as a model catalyst.Initial rate measurements showed that in both cases the hydrogenation is first order in hydrogen, zero order in the octadecenoate and a fractional order (close to one) in the catalyst.Both hydrogenations have similar activation energies (30.2 +/- 2.3 kJ mol-1 and 28.9 +/- 2.6 kJ mol-1 for the (Z)- and (E)-9-octadecenoate, respectively).Based on these data and the results of competition experiments, two models have been proposed to describe isomerization of the octadecenoates (either direct of via an intermediate).
- Krupickova, Jana,Vcelak, Jaroslav,Hetflejs, Jiri
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p. 2583 - 2592
(2007/10/02)
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- Epoxidation of Fatty Acid Esters with Aqueous Hydrogen Peroxide in the Presence of Molybdenum Oxide-Tributyltin Chloride on Charcoal Catalyst
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The epoxidation of fatty acid esters was carried out with a 30percent aqueous hydrogen peroxide in the presence of a molybdenum oxide-tributyltin chloride on a charcoal catalyst in 2-propanol at 50 degC.Such inner olefins as ethyl erucate and ethyl oleate gave good yields of 77 and 76percent, respectively.Ethyl elaidate, a trans-form of ethyl oleate, was less reactive (40percent yield).Several vegetable oils such as rapeseed oil, olive oil, soybean oil, cottonseed oil, corn oil, and linseed oil were oxidized with the oxirane oxygen contents of 5.3 to 3.5percent.
- Itoi, Yasushi,Inoue, Masami,Enomoto, Saburo
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p. 3941 - 3944
(2007/10/02)
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