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Abstract In the present study, Strachitunt, an Italian PDO cheese (PDO), traditionally produced starting from raw milk without addition of starter culture (SC) was compared for chemical, physical and microbiological characteristics to an experimental cheese (EC), produced from the same raw milk but with the addition of commercial SC. EC resulted in significantly lower in bacterial counts during the whole period considered (115 days of ripening), for Enterobacteriaceae, Coliforms, Enterococci and Staphylococcus aureus. Strachitunt fatty acids profile was not influenced by the cheese and it was dominated by saturated fatty acid. Volatile compounds analysis revealed that PDO and EC presented the typical aroma of blue veined cheese, where ketones as 2-pentanone, 2-heptanone and 2-nonanone were the most abundant compounds. Considering sensorial analysis, significantly higher scores were obtained for EC if compared to PDO. Highlights • Starter cultures resulted in microbial safety and better sensorial scores. • Starter cultures didn't influence cheese fatty acids profile. • Typical aroma of blue veined cheese was not changed by starter cultures. [ABSTRACT FROM AUTHOR]

Abstract A lack of well-established parameters and assessment values currently impairs biomonitoring of n-heptane exposure. Using controlled inhalation experiments, we collected information on urinary n-heptane metabolite concentrations and the time course of metabolite excretion. Relationships between external and internal exposure were analysed to investigate the suitability of selected metabolites to reflect n-heptane uptake. Twenty healthy, non-smoking males (aged 19–38 years, median 25.5) were exposed for 3 h to 167, 333 and 500 ppm n-heptane, each. Spot urine samples of the volunteers, collected before exposure and during the following 24 h, were analysed for heptane-2-one, 3-one, 4-one, 2,5-dione, 1-ol, 2-ol, 3-ol, and 4-ol using headspace solid phase dynamic extraction gas chromatography/mass spectrometry (HS-SPDE-GC/MS). Starting from median pre-exposure concentrations between <0.5 (3-one) and 82.9 μg/L (4-one), exposure increased the concentrations for all parameters except for 4-one. Median post-exposure concentrations ranged up to 840.4 μg/L (2-ol) and decreased with half-lifes <3 h after exposure. Non-parametric correlation analyses (n = 47, p < 0.05) revealed weak to moderate associations of volume related metabolite excretion with external exposure for 2-one, 3-one and 2,5-dione (R = 0.332–0.753). Heptanol excretion was moderately associated with exposure (R ≥ 0.509) only after creatinine adjustment. Lacking association with external exposure impedes the use of 4-one as heptane biomarker, whereas 2-ol and 3-ol turned out to be sensitive indicators of exposure if creatinine correction is applied. By providing fundamental data on a panel of eight potential heptane metabolites, our study can help to promote biological monitoring of n-heptane exposure. [ABSTRACT FROM AUTHOR]

Highlights • The combining of label-free cell phenotypic assay with 2DLC. • D1 activity location and D2 activity tracking obtained three β 2 -AR agonists. • The first time to discover diarylheptanoids with the β 2 -AR agonistic activity. • Providing possible explanation for the anti-asthmatic effect of C. zedoaria. Abstract Traditional Chinese Medicines (TCMs) have been widely used in clinical practice, and provided a rich source for discovering new drug leads. However, efficient identification of active molecules responsible for the therapeutic effects of complex TCMs is still highly challenging. Here, we combined label-free cell phenotypic assay with two dimensional liquid chromatography (2DLC) to identify potential β 2 -adrenoceptor (β 2 -AR) agonists related to anti-asthmatic effect of Curcuma zedoaria Rosc (C.zedoaria), a commonly used TCM. The ethyl acetate extract of C.zedoaria was first fractionated into 26 fractions. Label-free cell phenotypic profiling was then used to locate the active sites. Orthogonal second-dimensional (D2) separation was performed on two fractions displaying agonistic effect at the β 2 -AR, combined with screening of the D2 fractions to track the activity. Finally, this approach led to the isolation of three known diarylheptanoids, among which diarylheptanoid b exhibited the most potent agonistic activity with an EC 50 value of 5.93 μM. This result was further demonstrated through the chemical synthesis of diarylheptanoid b. It is the first time to discover that diarylheptanoids could activate the β 2 -AR, which may be responsible for the anti-asthmatic effect of C.zedoaria observed traditionally and in clinical application. This study also demonstrates the potential of this integrated strategy for identifying active ingredients and determining the basis of therapeutic materials in complex TCMs. [ABSTRACT FROM AUTHOR]

The social hierarchy of blackbuck plays a crucial role in mate selection and establishment of hierarchy in order to maintain successful reproduction. The factors that influence dominancy have not been yet investigated in the Indian male blackbuck. Here, we investigated the interrelationships between behaviours (aggressive and scent marking), chemical profiles of preorbital gland secretion and faecal testosterone levels in male blackbuck with special reference to dominance hierarchy. The frequency of aggressive behaviour, preorbital gland scent marking behaviour and faecal testosterone level were significantly higher (P <0.001) in the dominant males than the other males. Among the 43 major volatile compounds identified in the pre-orbital gland posting of dominant and subordinate male Blackbucks, four compounds viz., 2-methyl propanoic acid (I), 2-methyl-4-heptanone (II), 2,7-dimethyl-1-octanol (III) and 1,15-pentadecanediol (IV) were present only in the preorbital gland post of the dominant male during the hierarchy period. The results suggest that male blackbuck preorbital gland marking behaviour is meant to defend the home range or territorial region, and the scent odour suppresses aggression, scent marking, scent production and territorial patrolling of subordinate males. The behavioural expression, level of testosterone and volatile chemical profiles are closely interlinked towards establishment of dominance in the blackbuck. This investigation is the first of its kind to detect establishment of dominance hierarchy based on identification of volatile chemical compounds of preorbital gland and assessment of faecal testosterone in blackbuck. [ABSTRACT FROM AUTHOR]

A new series of diaryl heptanones ( 12a-q ) were synthesized and their structures were confirmed by its 1 H, 13 C NMR and Mass spectral data. These analogs were evaluated for their anti-oxidant activity and potential to inhibit 5-lipoxygenase. Compounds 12k and 12o showed potent in vitro 5-lipoxygenase enzyme inhibitory activity with IC 50 values of 22.2, 21.5 μM, which are comparable to curcumin (24.4 μM). Further they also have shown significant antioxidant activity. Molecular docking studies clearly showed correlation between binding energy and potency of these compounds. [ABSTRACT FROM AUTHOR]

Measurements of densities, ρ , ρ 123 and speeds of sound, u , u 123 of binary 1,3-dioxolane (1) + 1,4-dioxane (2) and ternary 1,3-dioxolane (1) + N-methylpyrrolidi-2-one or 1,4-dioxane (2) + cyclohexanone or cycloheptanone (3) mixtures have been carried out over the entire range of mole fraction at 293.15, 298.15, 303.15, 308.15 K and atmospheric pressure. The excess molar volumes, V 12 E , V 123 E and excess isentropic compressiblities, ( κ S E ) 12 , ( κ S E ) 123 have been determined from experimental data. The V 123 E and ( κ S E ) 123 data for 1,3-dioxolane (1) + N-methylpyrrolidin-2-one (2) + cyclohexanone or cycloheptanone (3) and 1,3-dioxolane (1) + 1,4-dioxane (2) + cycloheptanone (3) mixture are negative over entire composition of (1) and (2). While V 123 E for 1,3-dioxolane (1) + 1,4-dioxane (2) + cyclohexanone (3) are positive across full range of compositions of (1) and (2); the sign and magnitude of ( κ S E ) 123 values vary with change in composition of the constituent molecules. The V 12 E , V 123 E and ( κ S E ) 12 , ( κ S E ) 123 data have been fitted to Redlich-Kister equation to determine binary, ternary adjustable parameters and standard deviations. The V 123 E and ( κ S E ) 123 data have been analyzed in terms of Graph Theory. It has been observed that Graph theory correctly predicts the sign as well as magnitude of V 123 E and ( κ S E ) 123 data of the studied ternary mixtures. [ABSTRACT FROM AUTHOR]

Abstract A concise asymmetric total synthesis of Amaryllidaceae alkaloid (+)- trans -dihydronarciclasine is accomplished starting from optically pure 7-azabicyclo[2.2.1]heptanone scaffold in 13 linear steps. Key features of the strategy include substrate-directed stereoselective installation of the trans B-C ring junction and regioselective Wacker-type internal olefin oxidation to provide a rapid access to all hydroxyl functionalities over the key cyclohexane ring in a stereocontrolled manner. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

2-Heptanone (methyl n -amyl ketone) is a ketone that produces alarm reactions in insects (e.g., bees and ants). As an olfactory stimulus, 2-heptanone produces anxiety reactions in the short term and despair in the long term in rodent models. Among the anatomical connections of the olfactory system that integrate behavioral responses, connections between the amygdala and nucleus accumbens are important, which in turn form a circuit with the ventral tegmental area (VTA). 2-Heptanone increases the firing rate of amygdala neurons without participation of the vomeronasal organ. The olfactory amygdala-VTA-nucleus accumbens circuit may integrate defensive behaviors, but the possible actions of 2-heptanone on the responsivity of VTA-nucleus accumbens connections have not yet been explored. In the present study, multiunit activity recordings were obtained in adult Wistar rats from the core and shell subregions of the nucleus accumbens during electrical stimulation of the VTA under basal conditions and later during simultaneous stimulation of the VTA and olfactory exposure to 2-heptanone. 2-Heptanone reduced the responsivity of the VTA-nucleus accumbens shell but did not influence the responsivity of the VTA-nucleus accumbens core. The lower VTA-nucleus accumbens shell excitability may be related to a primary defensive warning when exposed to an alarm pheromone. [ABSTRACT FROM AUTHOR]

Pheromones are chemical substances released into the environment by an individual, which trigger stereotyped behaviors and/or physiological processes in individuals of the same species. Yet, a novel hypothesis has suggested that pheromones not only elicit innate responses but also contribute to behavioral plasticity by affecting the subjective evaluation of appetitive or aversive stimuli. To test this hypothesis, we exposed bees to three pheromonal components whose valence was either negative (i.e., associated with aversive events: isopentyl acetate and 2-heptanone) or positive (i.e., associated with appetitive events: geraniol). We then determined the effect of this exposure on the subjective evaluation of aversive stimuli by quantifying responsiveness to a series of increasing electric shock voltages before and after exposure. Two experiments were conducted varying the time-lapse between shock series (15 min in Experiment 1, and 24 h in Experiment 2). In Experiment 1, we observed a general decrease of shock responsiveness caused by fatigue, due to the short lapse of time between the two series of shocks. This decrease could only be counteracted by isopentyl acetate. The enhancing effect of isopentyl acetate on shock responsiveness was also found in Experiment 2. Conversely, geraniol decreased aversive responsiveness in this experiment; 2-heptanone did not affect aversive responsiveness in any experiment. Overall, our results demonstrate that certain pheromones modulate the salience of aversive stimuli according to their valence. In this way, they would affect the motivation to engage in aversive responses, thus acting as modulators of behavioral plasticity. [ABSTRACT FROM AUTHOR]

Excess molar enthalpies $$ H_{{}}^{\text{E}} $$ for binary 1,3-dioxolane (1) + 1,4-dioxane (2) or N-methylpyrrolidin-2-one (2) + cyclohexanone or cycloheptanone (3) and $$ H_{123}^{\text{E}} $$ for ternary 1,3-dioxolane (1) + N-methylpyrrolidin-2-one or 1,4-dioxane (2) + cyclohexanone or cycloheptanone (3) mixtures have been measured over the entire mole fraction range at 308.15 K and atmospheric pressure using a micro differential calorimeter (Model-l DSC 7 Evo). The $$ H_{{}}^{\text{E}} $$ and $$ H_{123}^{\text{E}} $$ data have been correlated with composition by fitting of the corresponding data to the Redlich-Kister equation. The topology of the constituent molecules (Graph theory) has been utilized to predict $$ H_{123}^{\text{E}} $$ values of the present mixtures. It is observed that the $$ H_{123}^{\text{E}} $$ values calculated by Graph theory compare well with their corresponding experimental values. The $$ H_{123}^{\text{E}} $$ data have also been tested in terms of the Prigogine-Flory-Patterson (PFP) theory. [ABSTRACT FROM AUTHOR]

Many bacteria, fungi, and plants produce volatile organic compounds (VOCs) emitted to the environment. Bacterial VOCs play an important role in interactions between microorganisms and in bacterial-plant interactions. Here, we show that such VOCs as ketones 2-heptanone, 2-nonanone, and 2-undecanone inhibit the DnaKJE-ClpB bichaperone dependent refolding of heat-inactivated bacterial luciferases. The inhibitory activity of ketones had highest effect in Escherichia coli ibpB::kan cells lacking small chaperone IbpB. Effect of ketones activity increased in the series: 2-pentanone, 2-undecanone, 2-heptanone, and 2-nonanone. These observations can be explained by the interaction of ketones with hydrophobic segments of heat-inactivated substrates and the competition with the chaperones IbpAB. If the small chaperone IbpB is absent in E. coli cells, the ketones block the hydrophobic segments of the polypeptides and inhibit the action of the bichaperone system. These results are consistent with the data on inhibitory effects of VOCs on survival of bacteria. It can be suggested that the inhibitory activity of the ketones indicated is associated with different ability of these substances to interact with hydrophobic segments in proteins. [ABSTRACT FROM AUTHOR]

Liquid-liquid equilibrium (LLE) for the ternary (3-heptanone + phenol + water) system has been determined under atmospheric pressure at 298.15 K, 303.15 K, 318.15 K and 323.15 K. The NRTL and UNIQUAC models were used to correlate the experimental results. The corresponding binary parameters were obtained and their physical meaning is explained by intermolecular attractive energy. The results from the two models agree well with experimental values. The NRTL model was more accurate than that of the UNIQUAC model. Meanwhile, the NRTL model was used to regress all the experimental values at different temperatures simultaneously, which is defined as total-regression. Compared with the individual regression by the NRTL model, the total regression by the NRTL model has fewer parameters and covers a wider interpolated range from 298.15 K to 323.15 K. The distribution coefficient for phenol changes with temperature. The phenol concentration can be expressed as a function of activity coefficient of phenol in both phases. The effect of temperature on the extraction performance of 3-heptanone was also investigated. The phenol extraction process by 3-heptanone is exothermic. The increase of temperature is not a benefit to phenol extraction. [ABSTRACT FROM AUTHOR]

The nematode Caenorhabditis elegans exhibits behavioral responses to a wide range of odorants associated with food and pathogens. A previous study described a Trojan Horse-like strategy of pathogenesis whereby the bacterium Bacillus nematocida B16 emits the volatile organic compound 2-heptanone to trap C. elegans for successful infection. Here, we further explored the receptor for 2-heptanone as well as the pathway involved in signal transduction in C. elegans. Our experiments showed that 2-heptanone sensing depended on the function of AWC neurons and a GPCR encoded by str-2. Consistent with the above observation, the HEK293 cells expressing STR-2 on their surfaces showed a transient elevation in intracellular Ca2+ levels after 2-heptanone applications. After combining the assays of RNA interference and gene mutants, we also identified theG subunits and their downstream components in the olfactory signal cascade that are necessary for responding to 2-heptanone, including Gα subunits of egl-30 and gpa-3, phospholipase C of plc-1and egl-8, and the calcium channel of cmk-1 and cal-1. Our work demonstrates for the first time that an integrated signaling pathway for 2-heptanone response in C. elegans involves recognition by GPCR STR-2, activation byGα subunits of egl-30/gpa-3 and transfer to the PLC pathway, indicating that a potentially novel olfactory pathway exists in AWC neurons. Meanwhile, since 2-heptanone, a metabolite from the pathogenic bacterium B. nematocida B16, can be sensed by C. elegans and thus strongly attract its host, our current work also suggested coevolution between the pathogenic microorganism and the chemosensory system in C. elegans. [ABSTRACT FROM AUTHOR]

Trapping brown rats is challenging because they avoid newly placed traps in their habitat. Herein, we report the identification of the sex pheromone produced by male brown rats and its effect on trap captures of wild female brown rats. Collecting urine- and feces-soiled bedding material of laboratory-kept rats and comparing the soiled-bedding odorants of juvenile and adult males, as well as of adult males and females, we found nine compounds that were specific to, or most prevalent in, the odor profiles of sexually mature adult males. When we added a synthetic blend of six of these compounds (2-heptanone, 4-heptanone, 3-ethyl-2-heptanone, 2-octanone, 2-nonanone, 4-nonanone) to one of two paired food-baited trap boxes, these boxes attracted significantly more laboratory-strain female rats in laboratory experiments, and captured ten times more wild female rats in a field experiment than the corresponding control boxes. Our data show that the pheromone facilitates captures of wild female brown rats. [ABSTRACT FROM AUTHOR]

Diarylheptanoids represent a group of plant secondary metabolites that possess multiple biological properties and are increasingly recognized for their therapeutic potential. A comparative study was performed on structurally analogous diarylheptanoids isolated from the bark of green ( Alnus viridis ) and black alder ( Alnus glutinosa ) to address their biological effects and determine structure-activity relationship. The structures and configurations of all compounds were elucidated by NMR, HR-ESI-MS, UV and IR. Diarylheptanoids actions were studied in human non-small cell lung carcinoma cells (NCI-H460) and normal keratinocytes (HaCaT). A. viridis compounds 3v, 5v, 8v and 9v that possess a carbonyl group at C-3 were considerably more potent than compounds without this group. A. viridis / A. glutinosa analogue pairs, 5v / 5g and 9v / 9g , which differ in the presence of 3′ and 3″-OH groups, were evaluated for anticancer activity and selectivity. 5v and 9v that do not possess 3′ and 3″-OH groups showed significantly higher cytotoxicity compared to analogues 5g and 9g . In addition, these two A. viridis compounds induced a more prominent apoptosis in both cell lines and an increase in subG 0 cell cycle phase, compared to their A. glutinosa analogues. 5v and 9v treatment triggered intracellular superoxide anion accumulation and notably decreased mitochondrial transmembrane potential. In HaCaT cells, 9v and 9g with a 4,5 double bond caused a more prominent loss of mitochondrial transmembrane potential compared to 5v and 5g which possess a 5-methoxy group instead. Although green alder diarylheptanoids 5v and 9v displayed higher cytotoxicity, their analogues from black alder 5g and 9g could be more favorable for therapeutic use since they were more active in cancer cells than in normal keratinocytes. These results indicate that minor differences in the chemical structure can greatly influence the effect of diarylheptanoids on apoptosis and redox status and determine their selectivity towards cancer cells. [ABSTRACT FROM AUTHOR]

The lesser (or small) chestnut weevil, Curculio sayi (Gyllenhal), is the key economic pest of chestnut in the central and eastern regions of the United States. Previous research identified the major components of the volatile profile emanating from several chestnut plant tissue types. The goal of this project was to evaluate for the first time the physiological (via electroantennogram) and behavioral (via Y-tube olfactometer) responsiveness of C. sayi to blends of selected key chestnut volatile organic compounds (VOCs) across weevil sex and seasonal period of adult activity. The VOC treatment mixtures that generated the highest (and mostly significant) mean electroantennogram (EAG) responses for both sexes and periods of adult activity were the 2-compound mixture treatments, specifically the treatments of 2-heptanone + ethyl butyrate, 2 heptanone + (E)-2-hexenal, and (E)-2-hexenal + ethyl butyrate. All 3- and 4-compound mixtures generated significantly lower mean EAG responses than most of the 2-compound mixture treatments. Results of the behavioral study did not reflect the results from the EAG study. Both male and female weevils, regardless of when they were collected during the season, did not exhibit a significantly greater preference towards any of the VOC mixture treatments compared with a control. As such, further studies must be conducted on additional chestnut VOCs in order to identify the optimal blend (and ratios of), as well as dosage, that will elicit a positive behavioral response before such VOCs can be utilized in a C. sayi monitoring and/or management practice. [ABSTRACT FROM AUTHOR]

1-Bromotricyclo[4.1.0.0]heptane reacted with benzene- and methanesulfonyl thiocyanates in benzene at 20°C via anti addition to the central C-C bicyclobutane bond with formation of 6- endo-bromo-6- exo-thiocyanato-7- syn-(R-sulfonyl)bicyclo[3.1.1]heptanes. Treatment of the benzenesulfonyl thiocyanate adduct with potassium tert-butoxide in THF at 20°C gave 7- endo-(benzenesulfonyl)norpinan-6-one, whereas the reaction with 1,8-diazabicyclo[5.4.0]undec-7-ene in methylene chloride afforded 7- exo-(benzenesulfonyl)-norpinane-6-thione which was converted into 7-exo-(benzenesulfonyl)norpinan-6-one by alkaline hydrolysis. [ABSTRACT FROM AUTHOR]

The effects of salts and pH on a mixture of homologous ketone flavours (2-hexanone, 2-heptanone and 2-octanone) binding to salt-extracted pea protein isolates (PPIs) were studied using GC/MS in an aqueous model system. Ionic strength, the specific flavour compound and pH were found to significantly affect protein-flavour binding. Comparing the univalent (NaCl) and divalent (CaCl 2 ) cations, higher concentrations of NaCl (0.25-1 M) greatly promoted protein-flavour binding compared to CaCl 2 , while lower concentrations (0.05-0.1 M NaCl and 0.25 M CaCl 2 ) decreased flavour retention. Considering the effect of anions (0.5 M), flavour binding by PPIs was dependent upon the position of the anions in the lyotropic series such that binding decreased in the order: Na 2 SO 4 >> NaCl > NaCH 3 COO = no salt > NaSCN. In terms of the effect of pH, overall flavour binding followed the order: pH 5 > pH 7 > pH 9 > pH 11 > pH 3. Competitive binding between the selected flavour mixture and PPIs was also observed as evidenced by 2-octanone more effectively binding to PPIs than 2-heptanone and 2-hexanone. This research supported existing knowledge on the effects of salts and pH on flavour partitioning with and without protein present. This further promotes utilization of plant proteins in aqueous food systems to achieve desired flavour attributes. [ABSTRACT FROM AUTHOR]

Quaternary centers are rapidly and selectively installed in a series of seven-membered and bridged cyclic oxonitriles through conjugate addition of an alkoxide to chloroalkenenitriles, followed by a Claisen rearrangement. Using this strategy, the stereogenic information of the carbinol in secondary allylic alcohols is transferred to the newly generated quaternary center. Experimentally, the sequence rapidly gives alkyl cyanocycloheptanones and bicycloalkanonecarbonitriles in good yield and with high selectivity, in a single synthetic operation. [ABSTRACT FROM AUTHOR]

The Baeyer–Villiger oxidation of cyclic ketones (I) to the corresponding lactones (II) can be improved using m -CPBA under microwave dielectric heating. A dramatic reduction of time—3 min compared to 5 days at room temperature—was observed to transform cycloheptanone into oxocan-2-one. Ω-Hydroxyalkyl hydroxamic acids (III), key intermediates for a rapid access to potent histone deacetylase inhibitors, are obtained in one-pot reaction of lactones using the Weinreb amidation. [ABSTRACT FROM AUTHOR]

Cholesterol oxidation in food and model systems is usually monitored by evaluating cholesterol oxidation products, but the analysis is time-consuming and expensive. Therefore, the determination of volatile compounds deriving from cholesterol thermoxidation could be valuable to identify other possible oxidation markers. Cholesterol alone and in the presence of a triacylglycerol mixture (tripalmitin, tristearin, and triolein) were thermoxidized at 170 °C for 15 min. In both model systems, the total volatile compounds increased three times when oxidation time rose from 5 to 15 min. The main classes of volatile compounds were aldehydes, ketones, alcohols and hydrocarbons, displaying a similar behavior in both systems. After 5 min of oxidation, 2-methyl-6-heptanone was the main volatile compound, followed by 3-methylpentane, 2,3-dimethyl-1-pentene and 3-methylbutanal. To verify if 2-methyl-6-heptanone could be used as volatile marker of cholesterol oxidation, data were compared with the total cholesterol oxidation products content of each system. A significant correlation between total cholesterol oxidation products content and 2-methyl-6-heptanone amount was found when cholesterol was oxidized alone ( r 2 = 0.994) and in presence of triacylglycerols ( r 2 = 0.998). When egg yolk was thermoxidized at 80 °C for 6 h, 3-methylbutanal was the volatile compound that better explained the oxidative trend in this food system, showing a significant correlation with cholesterol oxidation rate ( r = 0.91). In conclusion, 2-methyl-6-heptanone and 3-methylbutanal could represent an easy and cheaper strategy for monitoring cholesterol oxidation in model systems and food samples, respectively; however, a deeper investigation on the amount and type of volatile compounds generated from cholesterol oxidation according to the food matrix, should be carried out. [ABSTRACT FROM AUTHOR]

C 2 -symmetric ester-amide functionalized azolium salt was synthesized from readily available α-amino ester such as L -serine methyl ester. The combination of a Cu salt and the chiral azolium salt promoted the asymmetric conjugate addition reaction of enones with dialkylzincs. Thus, treatment of acyclic enone such as chalcone with Et 2 Zn afforded the corresponding 1,4-adduct with up to 85% ee. An excellent ee value of 93% was obtained when 3-nonen-2-one was reacted with Et 2 Zn. The present catalytic system was found to be useful for the 1,4-addition reaction of cyclic enone. For example, the reaction of 2-cyclohepten-1-one with Et 2 Zn produced ( R )-3-ethylcycloheptanone with 80% ee. [ABSTRACT FROM AUTHOR]

Since their discovery in insects, pheromones are considered as ubiquitous and stereotyped chemical messengers acting in intraspecific animal communication. Here we studied the effect of pheromones in a different context as we investigated their capacity to induce persistent modulations of associative learning and memory. We used honey bees, Apis mellifera, and combined olfactory conditioning and pheromone preexposure with disruption of neural activity and two-photon imaging of olfactory brain circuits, to characterize the effect of pheromones on olfactory learning and memory. Geraniol, an attractive pheromone component, and 2-heptanone, an aversive pheromone, improved and impaired, respectively, olfactory learning and memory via a durable modulation of appetitive motivation, which left odor processing unaffected. Consistently, interfering with aminergic circuits mediating appetitive motivation rescued or diminished the cognitive effects induced by pheromone components. We thus show that these chemical messengers act as important modulators of motivational processes and influence thereby animal cognition. David Baracchi et al. show that honey bees exposed to geraniol, a component of an attractant pheromone, exhibit improved olfactory learning and memory while the opposite effect was seen in honey bees exposed to the aversive pheromone, 2- heptanone. These changes occurred through a modulation of appetitive motivation without affecting odor processing, suggesting an important role for pheromones as modulators of motivational and learning processes. [ABSTRACT FROM AUTHOR]

Drift tube ion mobility spectrometers (DT IMS) allow the concentration of different organic compounds to be measured. This gives the opportunity to use these detectors in measuring the penetration of various substances through polymer membranes. Permeation measurements of two substances (2-heptanone and dimethyl methylphosphonate (DMMP)) through a cylindrical silicone rubber membrane were carried out. The membrane separated the aqueous solution from the air. The analyte was introduced into water, and then its concentration in air on the opposite side of the membrane was recorded. Based on the dynamics of detector signal changes, the diffusion coefficients for both tested substances were determined. Determination of permeability coefficients was based on precise quantitative measurements, which took into account the non-linearity of the detector characteristics and the effect of water on detection sensitivity. The analysis of measurement results was based on a mathematical description of diffusion process. [ABSTRACT FROM AUTHOR]

Abstract: In muroid rodents, urine-borne volatile compounds and major urinary proteins (MUPs) constitute the key male pheromones that shape the sexual attractiveness of males. Here, we aimed to examine whether male pheromone levels were related to sexual attractiveness and reproductive success in the North China subspecies of the brown rat (Rattus norvegicus humiliatus). According to the abundance of 2-heptanone (2H), the predominant male pheromone in male urine, male rats were first categorized into a high-2H group and a low-2H group. The levels of the whole volatile profile and non-volatile MUPs were found to be higher in the high-2H group than in the low-2H group. Moreover, the abundances of urinary volatile pheromones or pheromone candidates were positively correlated with the abundance of total MUPs. Two-way choice tests revealed that male urine from the high-2H group was more attractive to females than that from the low-2H group. Microsatellite loci analysis of paternal lineage revealed that the females had single-paternity offspring and that the high-2H group sired more offspring and had higher rates of paternity than did the low-2H group. These results suggest that urine-borne volatile pheromones alone or together with MUP pheromones can predict sexual attractiveness and reproductive success in male rats.Significance statement: Sexual attractiveness can be quantified using volatile and MUP pheromones and their candidates in deposited urine. 2-Heptanone (a major pheromone) and other urine-borne volatile pheromones or their candidates and total MUPs showed the same difference patterns in males and predicted male sexual attractiveness. The abundances of volatile pheromones or their candidates and total MUPs were associated with reproductive success and paternity rate in males. [ABSTRACT FROM AUTHOR]

Intramolecular endo-trig haloamination of 3-amino-2-azetidinones provides diaza-bicycloheptanone derivatives. [ABSTRACT FROM AUTHOR]