Synthesis Of Pheromone Research Articles

One-pot formation of aza-enolates from secondary amines and condensation to esters and alkyl bromides

Starting from commercial secondary amines, a one-pot procedure allows a direct access to enaminones through a one-pot deprotonation/oxidation/in situ re-deprotonation/acylation sequence without intermediate isolation of the intermediate Schiff base or its corresponding enamine tautomer. An alternative one-pot sequence involving a similar oxidation step followed by one or two alkylation steps yields, after acidic work-up, functionalized ketones directly from the parent amine. This process has been applied to an expeditious synthesis of the male aggregation pheromone of the cereal leaf beetle Oulema melanopus.

Improved synthesis of the chrysomelid pheromone (6R,7S)-(+)-himachala-9,11-diene via spontaneous bromination and didehydrobromination of 2,6,6,9-tetramethyl-bicyclo[5.4.0]undec-8-ene

A convenient synthesis of (6 R,7 S)-(+)-himachala-9,11-diene, the pheromone of the chrysomelid beetle Phyllotreta striolata is described. The diene is obtained in a single op eration by a spon- taneous bromination/dehydrobromination of 2,6,6,9-tetramethylbicyclo(5.4.0)undec-8-ene. The halogenation/dehalogenation sequence proceeds spontaneously in CCl 4, and is less uniform in CH 2Cl 2 and CHCl 3. 1 H NMR experiments carried out in presence of the radical scavenger di- tert -butyl-4-methylphenol suggest an ionic mechanism for this reaction. Theoretical calculations demonstrate that the spontaneous reaction profits f rom the strongly exergonic addition of Br 2 to the double bond and an almost neutral energy differ ence between the starting olefin and the diene pheromone.

Pheromone synthesis. Part 250: Determination of the stereostructure of CH503, a sex pheromone of male Drosophila melanogaster, as (3R,11Z,19Z)-3-acetoxy-11,19-octacosadien-1-ol by synthesis and chromatographic analysis of its eight isomers

All the eight stereoisomers of 3-acetoxy-11,19-octacosadien-1-ol (1), the male sex pheromone (CH503) of Drosophila melanogaster, were synthesized from two acetylenic starting materials and the enantiomers of 3,4-epoxy-1-butanol PMB ether. Complete separation of the eight isomers of 1 by reversed phase HPLC at −20 °C was achieved after their esterification with (1R,2R)-2-(2,3-anthracenedicarboximido)cyclohexanecarboxylic acid (27), and the natural CH503 was found to be (3R,11Z,19Z)-1.

Identification of a diacylglycerol acyltransferase 2 gene involved in pheromone biosynthesis activating neuropeptide stimulated pheromone production in Bombyx mori

Diacylglycerol acyltransferase (DGAT) catalyzes the final step in triacylglycerol biosynthesis. In the present study, a DGAT2 gene from Bombyx mori was characterized. Temporal expression profiles indicated that BmDGAT2 steadily increased from 96h before eclosion (−96h) to an expression peak in the pheromone glands (PGs) of new-emerged female (0h), a key stage for sex pheromone production. Spatial expression analysis revealed that the BmDGAT2 transcript was most richly expressed in PGs. Decapitation and subsequent methoprene, a juvenile hormone (JH) analog, treatment experiments revealed that JH had no influence on the expression of BmDGAT2 transcript before emergence, but inhibited the expression of BmDGAT2 transcript when administered to newly emerged adults. Further RNAi analysis confirmed that the decrease in BmDGAT2 mRNA level caused a significant reduction in sex pheromone production. Thus, DGAT2 is a key enzyme regulating B. mori sex pheromone synthesis and release.

A facile synthesis of the sex pheromone of Grapholitha molesta

The sex pheromone of Grapholitha molesta, (Z/E)-8-dodecylen-1-ol acetate, was easily synthesized in an overall yield of 41.5% with 1,8-octanediol as starting material via mono-esterification, PCC oxidation, and Witting reactions. The Z/E ratio is 83:17. Configuration transformation of Z/E 83:17 compound with sodium nitrite and nitric acid resulted in the production of a compound with Z/E 24:76. The products were confirmed by IR, 1H NMR, and MS spectral data.

Identification of Lipases Involved in PBAN Stimulated Pheromone Production in Bombyx mori Using the DGE and RNAi Approaches

BackgroundPheromone biosynthesis activating neuropeptide (PBAN) is a neurohormone that regulates sex pheromone synthesis in female moths. Bombyx mori is a model organism that has been used to explore the signal transduction pattern of PBAN, which is mediated by a G-protein coupled receptor (GPCR). Although significant progress has been made in elucidating PBAN-regulated lipolysis that releases the precursor of the sex pheromone, little is known about the molecular components involved in this step. To better elucidate the molecular mechanisms of PBAN-stimulated lipolysis of cytoplasmic lipid droplets (LDs), the associated lipase genes involved in PBAN- regulated sex pheromone biosynthesis were identified using digital gene expression (DGE) and subsequent RNA interference (RNAi).ResultsThree DGE libraries were constructed from pheromone glands (PGs) at different developed stages, namely, 72 hours before eclosion (−72 h), new emergence (0 h) and 72 h after eclosion (72 h), to investigate the gene expression profiles during PG development. The DGE evaluated over 5.6 million clean tags in each PG sample and revealed numerous genes that were differentially expressed at these stages. Most importantly, seven lipases were found to be richly expressed during the key stage of sex pheromone synthesis and release (new emergence). RNAi-mediated knockdown confirmed for the first time that four of these seven lipases play important roles in sex pheromone synthesis.ConclusionThis study has identified four lipases directly involved in PBAN-stimulated sex pheromone biosynthesis, which improve our understanding of the lipases involved in releasing bombykol precursors from triacylglycerols (TAGs) within the cytoplasmic LDs.

(R)-Desmolactone, A Female-produced Sex Pheromone Component of the Cerambycid Beetle Desmocerus californicus californicus (subfamily Lepturinae)

We report the identification, synthesis, and field bioassays of a female-produced sex attractant pheromone for the cerambycid beetle Desmocerus californicus californicus Horn. Headspace volatiles from females contained a sex-specific compound, (R)-desmolactone [(4R,9Z)-hexadec-9-en-4-olide], which elicited strong responses from the antennae of adult males in coupled gas chromatography-electroantennogram analyses. Short syntheses of both enantiomers were developed from commercial chiral synthons. In field bioassays, significant numbers of males were collected in traps baited with (R)-desmolactone, whereas the (S)-enantiomer attracted no males. The racemate was less attractive than the pure (R)-enantiomer, indicating some degree of antagonism by the unnatural enantiomer. This compound is the first example of a new structural class of cerambycid pheromones, and is the second pheromone identified for a species in the subfamily Lepturinae.

Pheromone synthesis. Part 249: Syntheses of methyl (R,E)-2,4,5-tetradecatrienoate and methyl (2E,4Z)-2,4-decadienoate, the pheromone components of the male dried bean beetle, Acanthoscelides obtectus (Say)

The enantiomers of methyl (E)-2,4,5-tetradecatrienoate (1), a component of the male pheromone of Acanthoscelides obtectus, were synthesized from the enantiomers of 1-undecyn-3-ol (6), which were obtained via asymmetric acetylation of (±)-1-trimethylsilyl-1-undecyn-3-ol (4) with vinyl acetate as catalyzed by lipase PS (Amano). The ortho ester Claisen rearrangement of 6 with triethyl orthoacetate was the key-step to generate the chiral allenic system. A new synthesis of (±)-1 was also executed starting from (±)-6. Three different syntheses of methyl (2E,4Z)-2,4-decadienoate (2), another component of the male pheromone of A. obtectus, were achieved by means of either palladium-catalyzed Heck reaction or a Claisen and an Al2O3 catalyzed thermal rearrangements.

Cover Picture: Asymmetric Synthesis of Both Enantiomers of Disparlure (Chin. J. Chem. 1/2012)

The cover picture shows a new and expeditious approach for the synthesis of disparlure and its enantiomer. The disparlure is the sex pheromone of the Gypsy moth Porthetria dispar L., which is used to monitor the Gypsy moth and protect plants against these pests. Starting from propargyl alcohol, and on the basis of Zhou's modified Sharpless asymmetric epoxidation, the sex pheromone of the Gypsy moth, disparlure and its enantiomer have been synthesized, each in six steps, with overall yields of 29% and 27% (ee>98%), respectively. The use of the sequential coupling tactic renders the method flexible, which is applicable to the synthesis of other cis-epoxy pheromones. More details are discussed in the article by Zheng et al. on page 23–28.

Erratum to: Identification, Synthesis, and Bioassay of a Male-Specific Aggregation Pheromone from the Harlequin Bug, Murgantia histrionica

Erratum to: Identification, Synthesis, and Bioassay of a Male-Specific Aggregation Pheromone from the Harlequin Bug, Murgantia histrionica

Chemoenzymatic synthesis of the alarm pheromone (+)-verbenone from geranyl diphosphate

The enzyme-guided asymmetric synthesis of (+)-verbenone from geranyl diphosphate in a simple two-step, one pot transformation highlights the potential of chemoenzymatic procedures for the generation of high-value terpenoids.

Asymmetric Synthesis of Both Enantiomers of Disparlure

AbstractStarting from propargyl alcohol (12), and on the basis of Zhou's modified Sharpless asymmetric epoxidation, the sex pheromone of the Gypsy moth, disparlure (+)‐8 and its enantiomer (−)‐8 have been synthesized, each in six steps, with overall yields of 29% for (+)‐8 and 27% for (−)‐8 (ee>98%). The use of the sequential coupling tactic renders the method flexible, which is applicable to the synthesis of other cis‐epoxy pheromones.

Chemoenzymatic Synthesis of Stegobinone and Stegobiol, Components of the Natural Sex Pheromone of the Drugstore Beetle (Stegobium paniceum L.) (Eur. J. Org. Chem. 1/2012)

AbstractThe cover picture shows drugstore beetles (Stegobium paniceum) abandoning their wooden tunnel nests to urgently follow the female‐produced sex pheromone. The chemoenzymatic stereoselective synthesis of the two components of the natural sex pheromone of the drugstore beetle was achieved by using ketoreductases in the key steps. Crystalline stegobinone was obtained free of its 1′‐epimer, which is strongly repellent to Stegobium paniceum. The authors thank the young architect George Orfanopoulos for the graphical design. The photographs of the drugstore beetle were taken from http://en.wikipedia.org/wiki/File:Drugstore_beetle_03.jpg under permission of http://creativecommons.org/licenses/by‐sa/3.0/deed.en. Details of the chemoenzymatic synthesis of the sex pheromone are discussed in the Short Communication by D. Kalaitzakis and I. Smonou on p. 43 ff. magnified image

Prerelease Exposure to Methyl Eugenol Increases the Mating Competitiveness of Sterile Males of the Oriental Fruit Fly (Diptera: Tephritidae) in a Hawaiian Orchard

Males of the oriental fruit fly, Bactrocera dorsalis (Hendel), are strongly attracted to methyl eugenol (ME), and recent work demonstrated that ingestion of this chemical enhances male mating success, apparently owing its role as a precursor in the synthesis of the male sex pheromone. The current study expanded upon earlier laboratory and field-cage experiments by assessing whether prerelease exposure to ME increased the mating competitiveness of mass-reared, sterile males in Hawaiian orchards. Releases of sterile males from a pupal color-based sexing strain were made weekly in two fruit orchards over 8 mo, with the sterile males at one site given ME for 24 h before release (treated) and the sterile males at the other site given no ME before release (control). Fruits were collected periodically during the study period, and eggs were dissected and incubated to score hatch rate. At both sites, releases of sterile males increased the proportion of unhatched eggs well above prerelease levels, but the incidence of egg sterility was consistently, and statistically, greater in the orchard receiving ME-exposed males. Computed over the entire release period, the average value of Fried's competitive index (that characterizes the mating success of sterile males relative to their wild counterparts) for ME-treated males was 3.5 times greater than that for control males, although this difference was not statistically significant. However, when computed over the period during which egg sterility values were elevated and stable, presumably when females inseminated before the releases were rare or absent, the competitive indices were significantly higher for ME-treated sterile males. The implications of these results for implementing the Sterile Insect Technique against this species are discussed.

Reproductive Regulating Pheromones of Queen Ant: A Short and Versatile Synthesis of 3,11-Dimethylheptacosane

Social behavior of insects always fascinates human beings as they appear to maintain good order and communication in the society. Insects have developed sophisticated chemical communication systems using their pheromones for the purpose. Among the pheromones, cuticular wax is used to recognize group members from non-members. In ants, there have been identified close to 1,000 cuticular hydrocarbons (CHCs) and the composition of CHCs of cuticles works for the discrimination between their friends and foes. Some species of ants are known to use cuticular wax of the dead ants in other colonies to disguise their identity when they invade other colonies. It was known that the antennae of ants recognize the composition of the CHCs but the exact mechanism of this recognition has not been well studied. The CHCs on the cuticles are also used to distinguish the queen ant from other fertile ants. Queen ants produce 3,11dimethylated linear hydrocarbons longer than C26 (Figure 1). Interestingly, only the odd numbered carbon chains ranging from 27 to 33 are found in insect society. These CHCs are also coated on the eggs of the queen but do not exist on those of other ants, which allow ants to distinguish those eggs and destroy the latter by eating to control their social hierarchy. We became interested in the recognition mechanism of the different composition of CHCs and the effect of the disruption of CHC composition on the social behavior of ants. For these studies, we need to devise a versatile synthetic route to these branched hydrocarbons. Herein, we report the first synthesis of 3,11-dimethylheptacosane (1) through a short and versatile synthetic route. The synthetic analysis of 3,11-dimethylheptacosane (1) shows that intermolecular enyne metathesis can allow to introduce two methyl group on the chain and the overall chain length could be controlled by using an alkyne with proper chain length (Scheme 1). Two methyl groups of 1 can be obtained from two conjugated dienes of 2. These two diene fragments, 3 and 4, can be prepared through enyne metathesis of tosylated butynol 6 with proper olefin. This synthesis would not require any protecting group and allows that alkyne 5 could be replaced by other alkynes with different chain length for the synthesis of all possible CHC pheromones. The synthesis started from 3-butynol to produce the corresponding tosylate 6. The alkyne 6 was treated with the second generation Grubbs catalyst (Grubbs II) under ethylene atmosphere to produce diene 3. Since allyl bromide was not

‘Popping the Clutch’: Novel Mechanisms Regulating Sexual Development in Cryptococcus neoformans

Sexual reproduction in fungal pathogens such as Cryptococcus provides natural selection and adaptation of the organisms to environmental conditions by allowing beneficial mutations to spread. However, successful mating in these fungi requires a time-critical induction of signaling pheromones when appropriate partners become available. Recently, it has been shown that the fungus uses the transcriptional equivalent of the racing technique: 'popping the clutch'-pushing in the clutch pedal, putting the car in gear, revving with the gas pedal, and then dropping the clutch pedal to accelerate rapidly. In the same way, Cryptococcus during vegetative growth constitutively matches a high rate of pheromone synthesis with a high rate of degradation to produce repressed levels of transcript. Then, when mating is required, the fungus drops the degradative machinery, resulting in a rapid induction of the pheromone. Pairing with this novel regulatory cycle is a host of mitogen-activated protein kinase cascades, cyclic AMP-dependent, and calcium-calcineurin signaling pathways that maintain these high rates of pheromone synthesis and prime downstream pathways for an effective mating response. The intersection of a number of virulence-associated traits with sexual development such as the synthesis of an immune-disruptive laccase as well as a protective polysaccharide capsule makes these rapid regulatory strategies a formidable foe in the battle against human disease.

Pheromone synthesis in a biomicroreactor coated with anti-adsorption polyelectrolyte multilayer.

To prepare a biosynthetic module in an infochemical communication project, we designed a silicon/glass microreactor with anti-adsorption polyelectrolyte multilayer coating and immobilized alcohol acetyl transferase (atf), one of the key biosynthetic enzymes of the pheromone of Spodoptera littoralis, on agarose beads inside. The system reproduces the last step of the biosynthesis in which the precursor diene alcohol (Z,E)-9,11-tetradecadienol is transformed into the major component (Z,E)-9,11-tetradecadienyl acetate. The scope of this study was to analyze and implement a multilayer, anti-adsorption coating based on layer-by-layer deposition of polyethylenimine/dextransulfate sodium salt (PEI/DSS). The multilayers were composed of two PEI with molecular weights 750 and 1.2 kDa at pH 9.2 or 6.0. Growth, morphology, and stability of the layers were analyzed by ellipsometry and atomic force microscopy (AFM). The anti-adsorption functionality of the multilayer inside the microreactor was validated. The activity of His(6)-(atf) was measured by gas chromatography coupled to mass spectrometer (GC-MS).

Review of Chemical Synthesis of Hormones, Pheromones and Other Bioregulators

ADVERTISEMENT RETURN TO ISSUEPREVBook ReviewNEXTReview of Chemical Synthesis of Hormones, Pheromones and Other BioregulatorsQiao-Hong ChenView Author Information Virginia TechBlacksburg, VirginiaCite this: J. Nat. Prod. 2011, 74, 7, 1671Publication Date (Web):June 23, 2011Publication History Published online23 June 2011Published inissue 22 July 2011https://doi.org/10.1021/np200497hCopyright © 2011 The American Chemical Society and American Society of PharmacognosyRIGHTS & PERMISSIONSArticle Views360Altmetric-Citations28LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit Read OnlinePDF (618 KB) Get e-AlertsSUBJECTS:Chemical synthesis,Molecules,Organic synthesis,Pharmaceuticals Get e-Alerts

Stereoselective synthesis of the obscure mealybug pheromone by hydrogenation of a tetrasubstituted alkene precursor

An improved diastereoselective synthesis of (1R∗,2R∗,3S∗)-1-acetoxymethyl-2,3,4,4-tetramethylcyclopentane 1, the sex pheromone of the obscure mealybug, Pseudococcus viburni, is described. The key step was diastereoselective catalytic hydrogenation of the tetrasubstituted double bond in 2,3,4,4-tetramethyl-cyclopent-2-enone 4 to give the thermodynamically less favored cis-2,3,4,4-tetramethyl-cyclopentanone 3a.

Chemical Synthesis of Hormones, Pheromones and Other Bioregulators. By Kenji Mori.

John Wiley & Sons, Hoboken 2010. 314 pp., softcover, € 48.90.—ISBN 978-0470697238