Search

An ischemic cerebral stroke results from the interruption of blood flow to the brain, triggering rapid and complex cascades of excitotoxicity, oxidative stress, and inflammation. Current reperfusion therapies, including intravenous thrombolysis and mechanical thrombectomy, cause further brain injury due to reperfusion-induced cytotoxicity. To date, novel cytoprotective therapies that could address these challenges have yet to be developed, likely due to the limitations of targeting a single pathologic mechanism. To address these unmet clinical needs, we investigated a synthetic verbenone derivative, SP-8356, as a potential multi-target cytoprotective agent for acute ischemic strokes. In transient middle cerebral artery occlusion (MCAO) rats, SP-8356 significantly reduced brain infarct and edema volumes while improving acute neurological deficits in a dose-dependent manner. Furthermore, SP-8356 improved long-term outcomes, particularly by reducing mortality. These potent cytoprotective effects of SP-8356 were achieved by suppressing the excessive production of free radicals and pro-inflammatory cytokines, reducing the infiltration of inflammatory cells, and mitigating increases in blood–brain barrier permeability. Additional research is needed to determine whether co-administration of SP-8356 can extend the therapeutic time window of reperfusion therapies by mitigating ischemia/reperfusion injury. [ABSTRACT FROM AUTHOR]

Free radicals are produced in diabetes mellitus (DM), due to protein glycosylation and glucose autooxidation. However, plant compounds have been proven to be effective in managing DM and related conditions. This study evaluated the antioxidant effect of verbenone and L-arginine in diabetic mice. DM was induced in mice by intraperitoneal (IP) injection of 60 mg/kg body weight of streptozotocin and 120 mg/kg body weight of nicotinamide adenine dinucleotide (NAD). The diabetic mice were treated afterwards with verbenone, L-arginine, and their ratios at 100 and 200 mg/kg body weight for 14 days respectively. In the in vitro study, L-arginine expressed higher 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, while verbenone and L-arginine expressed higher nitric oxide (NO) and hydrogen peroxide (H2O2) scavenging activities, especially at higher concentrations when compared with vitamin C. At the end of the treatment period, the levels of blood glucose, total protein, and malondialdehyde were significantly increased while the levels of reduced glutathione, nitrite, and activities of glutathione peroxidase, glutathione transferase, catalase, superoxide dismutase were significantly decreased in the diabetic untreated mice. However, these diabetes-induced alterations were reversed to normal levels after the administration of verbenone, L-arginine, and their ratio combinations at 100 and 200 mg/kg body weight. Furthermore, in silico studies revealed the antioxidant potential of both verbenone and L-arginine by their interaction with antioxidant proteins, expressing their potential antioxidant properties. The results of the study indicated that verbenone, L-arginine, and their ratio combination possess antioxidant properties and attenuate oxidative stress in diabetic mice. [ABSTRACT FROM AUTHOR]

The European spruce bark beetle, Ips typographus (L.), is the most important forest pest in Europe due to the profound impacts of periodic outbreaks on ecosystem goods and services. Herein, we evaluated the responses of I. typographus to different doses of verbenone (SPLAT® Verb, 10% (−)‐verbenone by weight; ISCA Inc., Riverside, CA, USA) in traps baited with its aggregation pheromones. Results are based on 1,492,289 I. typographus collected in five experiments over 3 years. SPLAT® Verb inhibited the response of I. typographus to baited traps out to 14 m from the point of release (dollop) and for >80 days at a dose of 75 g per dollop. Reductions in trap catch ranged from 34% to 93% depending on the dose of verbenone, age of SPLAT® Verb dollops, distance from dollops and the environment. In forest stands, significant reductions in trap catch were observed at distances up to 14 m from the point of release, with the largest reductions observed at 0 m (93%) and 2 m (64%). In an open area, significant reductions in trap catch were observed at distances up to only 2 m from the point of release, with the largest reduction observed at 0 m (66%). The much lower active inhibitory range of verbenone in the open area appears to be explained by less stable accumulations of verbenone in the surrounding air. There was a significant negative correlation between trap catch and the amount of verbenone measured in air in the vicinity of traps. We also observed inhibition of the sixtoothed spruce bark beetle, Pityogenes chalcographus (L.), another important forest pest in Europe, at all doses (20, 40, 75 and 100 g) of SPLAT® Verb that were evaluated. The implications of these and other results to the management of I. typographus are discussed. [ABSTRACT FROM AUTHOR]

Objective: Aedes aegypti (L., 1762) (Diptera: Culicidae) is a vector for numerous viral diseases including dengue fever, Chikungunya, Zika fever, and yellow fever in densely populated urban areas. Mosquito control programs rely heavily on applying larvicides in breeding areas and applying insecticides targeting adult mosquitoes in the Ae. aegypti populations. Essential oils are primarily composed of terpenoids and phenylpropanoids and have a range of beneficial properties, including insecticidal activities. Methods: This study primarily investigated the ovicidal and larvicidal activity of selected chemicals (verbenone, propionic acid, lactic acid, 1-butanol, 2-butanol and citronellol) identified in essential oils of plants against Ae. aegypti in wells of 24-well plates. Results: Verbenone, propionic acid and lactic acid were observed to present a dose dependent effect on mosquito larvae. Verbenone emerged as the most effective against larvae with an LC50 value of 29.369 ppm. Propionic acid and lactic acid were highly effective with LC50 values ranging between 40.45-47.63 ppm. 1-butanol, 2-butanol and citronellol did not cause any mortality. This study is among the few studies that have assessed the ovicidal effects of essential oils on mosquito eggs. After 120 hours of exposure, verbenone, propionic acid and 1-butanol were observed to present a dose dependent effect on mosquito eggs. Verbenone also emerged as the most effective against eggs with an LC50 value of 11.877 ppm. At 200 and 100 ppm <25% hatched but afterwards a drastic increase in egg hatching was observed with decreased with concentration. Conclusion: EOs have promising potential as a safe and effective larvicidal and ovicidal agent for controlling Aedes mosquito populations. Such studies pave the way for developing new mosquito control formulations utilizing these effective essential oils. [ABSTRACT FROM AUTHOR]

The Ceratocystis fungal disease complex, rapid ʻōhiʻa death (ROD), has killed over one million ʻōhiʻa (Metrosideros polymorpha), the keystone tree species of Hawaiʻi. The causal fungi can be spread by invasive ambrosia beetles (Coleoptera: Curculionidae) through fungal inoculum found on their bodies and in the frass they produce. Thus, there is a critical need to manage beetle attack on ʻōhiʻa trees to curtail subsequent pathogen spread and disease development. In this experiment at Waiākea Forest Reserve, we tested the potential of the semiochemical repellent, verbenone, in a commercial formulation, to protect healthy and ROD-affected ʻōhiʻa from ambrosia beetle attack in each of the 2022 and 2023 field seasons. Landing rates of ambrosia beetles on healthy and diseased trees were quantified over 16 weeks each year, using sticky traps on ethanol-baited trees that also received either a low (72 g) or high (108 g) dose of verbenone or untreated controls. In addition, we used gas-chromatography mass-spectrometry (GC–MS) to measure verbenone emission over 16 weeks in 2022. We found that the low dose of verbenone is the most effective and economical application to reduce beetle landing on healthy ʻōhiʻa trees and the high dose may be needed to reduce attraction to diseased ʻōhiʻa. Despite a large decrease in verbenone emission levels by week eight, the low dose effectively reduced beetle captures on healthy trees for 14 weeks and the high dose reduced landing rates on diseased trees for 10–14 weeks. Our results indicate verbenone may significantly lower ambrosia beetle attack on ʻōhiʻa, and thus, lead to reduction in the spread of ROD.

Early detection of invasive species is critical for preventing ecological and economic damage and maintaining ecosystem health. In Hawaiʻi, a complex of generalist ambrosia beetle species in the tribe Xyleborini (Coleoptera: Scolytinae) are threatening the health and productivity of forests and crops due to their association with tree diseases such as rapid ʻōhiʻa death (ROD) and key agricultural commodities including coffee and macadamia.We conducted trapping experiments to determine the efficacy of semiochemicals to attract and repel Xyleborini ambrosia beetles within two ʻōhiʻa (Metrosideros polymorpha) forests on the Island of Hawaiʻi. We compared the attraction of beetles to 100% ethanol and a 1:1 mixture of ethanol: methanol at Waiākea Forest Reserve and ʻŌlaʻa Forest in Hawaiʻi Volcanoes National Park. In addition, we tested the extent to which verbenone and verbenone + methyl salicylate repellents (SPLAT® Verb and SPLAT® Beetle Guard, respectively) deterred beetles from baited traps at Waiākea Forest Reserve in two separate experiments.For all invasive ambrosia beetle species, including Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xyleborus perforans, Xylosandrus compactus, and Xylosandrus crassiusculus, more beetles were captured in traps baited with 100% ethanol than 1:1 ethanol: methanol. Across all species, both repellents were effective, with fewer beetles captured in traps equipped with repellents.Our research demonstrates the utility of semiochemicals for attracting and repelling invasive ambrosia beetle species in Hawaiʻi, and the potential use of these tools for early detection and management strategies. [ABSTRACT FROM AUTHOR]

Bark beetles are an economically and ecologically important insect group, with aggregation behavior and thus host colonization success depends on pheromone‐mediated communication. For some species, such as the major invasive forest pest in China, red turpentine beetle (Dendroctonus valens), gut microbiota participates in pheromone production by converting tree monoterpenes into pheromone products. However, how variation in gut microenvironment, such as pH, affects the gut microbial composition, and consequently pheromone production, is unknown. In this study, we fed wild caught D. valens with 3 different pH media (main host diet with natural pH of 4.7; a mildly acidic diet with pH 6 mimicking the beetle gut pH; and highly acidic diet with pH 4), and measured their effects on the gut pH, bacterial community and production of the main aggregation and anti‐aggregation pheromone (verbenone). We further tested the verbenone production capacity of 2 gut bacterial isolates in different pH environments (pH 6 and 4). Compared to natural state or main host diet, feeding on less acidic diet (pH 6) diluted the acidity of the gut, whereas feeding on highly acidic diet (pH 4) enhanced it. Both changes in gut pH reduced the abundance of dominant bacterial genera, resulting in decreased verbenone production. Similarly, the highest pheromone conversion rate of the bacterial isolates was observed in pH mimicking the acidity in beetle gut. Taken together, these results indicate that changes in gut pH can affect gut microbiota composition and pheromone production, and may therefore have the potential to affect host colonization behavior. [ABSTRACT FROM AUTHOR]

Tree-killing bark beetles require rapid management, such as anti-attractants, to stop the enlargement of attack hot-spots. We tested two newer anti-attractant blends, both without verbenone and one with the addition of trans-4-thujanol, in traps against standard pheromone baits for inhibition of catch. Both blends provided effective catch reduction (>95%). We also tested these anti-attractant blends in tree protection experiments for two years. We had experimental plots with a center of an anti-attractant protected tree zone, with no traditional control area, but we followed tree kills in 10 m wide concentric rings to 100 m. In 2020, we had 12 plots, and 9 plots in 2021. Monitoring by low-strength pheromone traps followed beetle flight averaging 300/trap during the shorter period, August 2020, and 5000/trap during the longer period, May to August 2021. The blends of anti-attractants were 100% effective in avoiding tree mortality in both treated trees and their surroundings. There were no bark beetle attacks on any treated trees, and there was zero tree mortality up to 19 m in 2020, and up to 30 m in 2021, thus full protection to circa 20 m. The density of killed trees then increased from close to zero, over 20 to 50 m, reaching a level of ca 30 (trees/ha) then declined. The spatial pattern of tree mortality on our experimental plots was highly heterogeneous and individual 10m-ring data points on tree kill density could not be statistically separated. In contrast, a non-linear regression model showed a continuous increase of attacks over the distance from the center to a peak ca 60m, followed by a decline. This model agrees partly with the only similar study in the literature, but importantly, it does not give a peak of kill density at distances between the first and second rings close to treatment zones. Such patterns of close-quarter kills have been observed as a "switching" of attack in this and other scolytid systems manipulated by anti-attractants, but not in the present study, likely due to the elimination of verbenone from our blends. [ABSTRACT FROM AUTHOR]

Individuals across various animal species communicate their presence to conspecifics. Especially phytophagous and parasitoid insects with their brood developing on limited resources rely on chemical cues, such as host-marking pheromones, to reduce intraspecific competition. Bark beetles are phytophagous insects with some species being economically and ecologically relevant forest pests. Several of them use the volatile compound verbenone to inhibit attraction and reduce intraspecific competition. However, in the Eurasian spruce bark beetle, Ips typographus (L.), temporal emission patterns did so far not quite support the putative function of verbenone as an indicator of densely colonised host trees. More importantly, it is currently unclear how well verbenone emission is actually related to colonisation density and thus intraspecific competition. Here, we inoculated Norway spruce logs with I. typographus at two defined colonisation densities in the greenhouse and measured the emission of verbenone and its precursors α-pinene and verbenol over time. Verbenone emission was 3–7 times greater from colonised logs compared to decaying logs without beetles during the major part of larval development. Furthermore, our data supports the quantitative hypothesis, that the termination of attack on a tree is mediated by a cessation of the release of verbenol and continuous emission of verbenone. The latter is most likely a passively produced host-marking cue reflecting the actual density of conspecifics since per-beetle emission was unaffected by colonisation density. These findings shed new light on the regulation of bark beetle mass aggregations, which are currently causing previously unseen economic damages in temperate forests. [ABSTRACT FROM AUTHOR]

Ips typographus, the European spruce bark beetle, is a destructive forest insect that attacks spruce trees. It poses a significant threat to the forestry industry, causing widespread tree mortality and economic losses, and its management through chemical ecology is a promising approach. Attraction relies on aggregation pheromones while repellency is achieved via antiaggregation pheromones combined with mixtures of nonhost volatiles (NHVs), but an effective push and pull strategy has not been established yet. In this study, we observed the beetle colonization dynamic and density comparing pure Norway spruce stacks and Norway spruce stacks with 20% Scots pine logs. We collected the spruce bark volatiles before the beetle colonization and at the end of the trial, and tested the behavioral effects on the beetles of both spruce and pine essential oils in olfactometer trials. In the stacks with Scots pine, we observed a delayed primary colonization and a 65% reduction of the secondary colonization, confirming the colonization disruption mediated by NHVs. Volatile analysis showed a significant change in the bark emission profiles, and the reaching of the antiaggregation phase was marked by the release of verbenone. Behavioral experiments confirmed the attractivity of spruce essential oil and the strong repellency of the pine essential oil. The study supports the use of complex NHVs blends for the beetle behavioral manipulation in the field. Further studies are needed to assess if the same results can be achieved by deploying essential oils in forest stands. [ABSTRACT FROM AUTHOR]

The diamondback moth is a detrimental insect pest of brassicaceous crops which was among the first crop insects to be reported as DDT resistant. It has since proven to be significantly resistant to nearly every synthetic insecticide used in the field in many crucifer-producing regions. Due to insecticide control failures in some parts of the world, economically viable crucifer production is now all but impossible. As a result, there has been an increasing effort to identify new compounds with strong pesticidal activity. Cantharidin is one such compound that has been shown to be highly effective against a variety of insect pests. However, its chemical synthesis and potential toxicity to non-target organisms have been a major source of concern. Herein, using rational design approaches, a new series of cantharidin-based verbenone derivatives were synthesized and evaluated for their insecticidal activities against the diamondback moth. Among different compounds screened, compounds 6a, 6h, 6i, and 6q emerged as the most potent compounds exhibiting 100% mortality at a concentration of 100 mg/L after four days. These compounds demonstrated a good anti-feeding effect against the diamondback moth on cabbage leaves. Subsequently, a 3D QSAR study was carried out to identify the key structural features of the synthesized compounds and their correlation with insecticidal activity. [ABSTRACT FROM AUTHOR]

Exotic ambrosia beetles (Coleoptera: Curculionidae: Scolytinae), such as Xylosandrus crassiusculus (Motschulsky), Xylosandrus germanus (Blandford), and Xylosandrus compactus (Eichoff) are serious pests in southeastern ornamental nurseries. Preventative pyrethroid trunk sprays effectively reduce boring damage. However, it is unclear how pyrethroids such as permethrin prevent attack. Thus, the objective was to determine how permethrin-treated bolts interact with invading ambrosia beetles. In 2022, a study with 2 independent trials was conducted in a nursery on red maple (Acer rubrum L.), bolts during March and April, respectively. The treatments were (i) nonbaited, nontreated bolt, (ii) ethanol baited bolt, (iii) nonbaited bolt + glue [painted on bolt], (iv) ethanol baited bolt + glue, (v) ethanol baited bolt + glue + permethrin, (vi) ethanol baited bolt + glue + permethrin + verbenone, and (vii) ethanol baited bolt + glue + verbenone. Ambrosia beetles trapped on glue, beetles which fell into the pail with soap solution under the bolts, and entry holes on bolts were quantified. Permethrin prevented beetle attacks but did not reduce the number of ambrosia beetles landing on the treated bolts. Verbenone reduced ambrosia beetles from landing on the bolts but did not prevent boring into bolts. The numbers of ambrosia beetles in soapy water were not significantly different among treatments. Ambrosia beetles are landing on permethrin-treated bolts but not boring into the bolts, implying that fresh permethrin residues may not be necessary for ambrosia beetle management. [ABSTRACT FROM AUTHOR]

α-Pinene is the terpene abundant in nature. It is present in the oils of coniferous trees, mainly pine. We demonstrate that from this renewable stock, high value-added products such as verbenone, verbenol, α-pinene oxide, can be obtained as the main products, and smaller quantities of pinanediol carvone myrtenol pinocarveol campholenic aldehyde, myrtenal, and carveol are also produced. All the products have numerous applications in medicine, cosmetics, and foods. Heterogeneous ZSM-5 zeolite catalysts with different aluminum contents – designated as (in wt% of Al) ZSM-5_1 (2.5), ZSM-5_2 (0.59), and ZSM-5_3 (0.38) – were applied in the green α-pinene oxidation with oxygen and without solvent. To date, the use of the ZSM-5 catalyst in the α-pinene oxidation process has not been described. The catalysts were characterized by UV-Vis, FTIR, EDXRF, XRD, SEM, DTA techniques, and by the nitrogen sorption method at 77 K. The effects of catalyst amount and properties, temperature and reaction time, on product selectivity and α-pinene conversion, were determined. [Display omitted] • Sustainable and green technology of α-pinene oxidation to high value-added products. • Efficient ZSM-5 zeolite catalysts for α-pinene oxidation with oxygen without solvent. • Mild optimal conditions: 49% conversion after 6 h at 95 °C and for 0.05 wt% catalyst. • Main high value-added products: α-pinene oxide, verbenol, and verbenone. • Respective selectivities of main products are: 28%, 16% and 18%. [ABSTRACT FROM AUTHOR]

Semiochemical‐based management strategies are important for controlling bark beetles, such as invasive Red Turpentine Beetle (Denroctonus valens), the causal agent for mass mortality of pine trees (Pinus spp.) in China. It has been previously shown that the pheromone verbenone regulates the attack density of this beetle in a dose‐dependent manner and that the gut bacteria of D. valens are involved in verbenone production. However, molecular functional verification of the role of gut bacteria in the pheromone production of D. valens is still lacking. To better understand the molecular function of gut bacterial verbenone production, we chose a facultative anaerobic gut bacterium (Enterobacter xiangfangensis) of D. valens based on its strong ability to convert cis‐verbenol to verbenone, as shown in our previous study, and investigated its transcriptomics in the presence or absence of cis‐verbenol under anaerobic conditions (simulating the anoxic environment in the beetle's gut). Based on this transcriptome analysis, aldehyde dehydrogenase (ALDH1) was identified as a putative key gene responsible for verbenone production and was knocked‐down by homologous recombination to obtain a mutant E. xiangfangensis strain. Our results show that these mutants had significantly decreased the ability to convert the monoterpene precursor to verbenone compared with the wild‐type bacteria, indicating that ALDH1 is primarily responsible for verbenone conversion for this bacterium species. These findings provide further mechanistic evidence of bacterially mediated pheromone production by D. valens, add new perspective for functional studies of gut bacteria in general, and may aid the development of new gene silencing‐based pest management strategies. [ABSTRACT FROM AUTHOR]

Highlights Verbenone, a natural bicyclic ketone monoterpene, and L-arginine, a natural amino acid, are both found in Daucus carota and other medicinal plants useful in the management of diabetes mellitus. Verbenone and L-arginine possess in vitro antidiabetic activities, improve glucose uptake, and inhibited haemoglobin glycation. Verbenone possesses in vivo antidiabetic activities in NAD-STZ-induced diabetic mice with potential synergetic effect with L-arginine. Verbenone and L-arginine possess antihyperlipidemic properties and could prevent the risk of cardiovascular diseases in NAD-STZ-treated mice.

In this work, carbon-supported nickel catalysts with different Ni content (1, 2.5, 5, 10, and 20 wt%) were tested in the oxidation of alpha-pinene in solvent-free reaction conditions. The process of catalyst preparation consisted of two stages. In the first stage, the activated carbon from spent coffee grounds was obtained. In the second stage, the active phase in the form of nickel compounds was applied using two methods: (1) the impregnation of the material with the nickel salt solution, and next reduction in H2, and (2) the hydrothermal method in the autoclave using the reductor and the reaction stabilizer. The obtained catalysts were subjected to the following instrumental studies: FT-IR, XRD, SEM, and N2 adsorption at −196 °C. The performed catalytic tests showed that the catalysts containing 5 wt% of Ni (porous material obtained by the impregnation method) and 1 wt% of Ni (porous material obtained by the hydrothermal method) were the most active in the oxidation of alpha-pinene, and the main oxidation products were alpha-pinene oxide, verbenol, and verbenone. Ultimately, the hydrothermal method of catalyst preparation turned out to be more advantageous because it allows one to obtain higher selectivities of the epoxide compound, probably due to the greater stability of this organic compound in pores. [ABSTRACT FROM AUTHOR]

A simple and convenient procedure for the γ, β-dimerization of verbenone was developed. The dimer was obtained during aging with KOH without a solvent. The process proceeds as the formation of the extended enolate of verbenone and its Michael addition to other molecules of verbenone. The product yield was 82% after purification by column chromatography and recrystallization. [ABSTRACT FROM AUTHOR]

Protection of Norway spruce stands using anti-attractants was tested during an outbreak of bark beetles (Ips typographus) in their spring flight. The aims of this study were as follows: (1) to test the proposed experimental design for tree protection; (2) to evaluate height-specific alternatives for dispenser installation on trees; and (3) to evaluate the efficiency of tree protection measures using anti-attractants under bark beetle infestation and drought stress. The experiment was conducted at the forest edges adjacent to recent clearcuts on 10 blocks in the eastern Czech Republic. Each block had three adjacent experimental areas, with 20 trees growing in two rows at the recently cut forest edge (10 trees per row). In front of a block in each of the three areas, four pheromone traps were installed. The treatment area was protected by anti-attractants. The second area served as a so-called switch area, where beetles from the treatment area, as the outflux redirected from the anti-attractant, would start new attacks if not caught in nearby pheromone traps. The third area was a control. We attached anti-attractant tube dispensers on each tree trunk of the treated area at two heights. The results suggest a redirecting effect of anti-attractants, pushing beetles into the switch area and causing subsequent attacks, which was greater than in areas containing treated trees. There was no difference between two dispensers placed at 1 and 8 m height and both at 1 m. A switching effect of beetle attacks occurring outside of the treated areas was observed. Mounting anti-attractant dispensers on tree trunks at one low position above the ground can be substantially less labour-intensive and as efficient as positioning them at two different heights. For areas affected by severe drought and extremely dense bark beetle populations, the use of anti-attractants did not prove effective. [ABSTRACT FROM AUTHOR]

Copper(II)-containing aluminum phosphate material (CuAPO-5) was synthesized hydrothermally and used as a multiphase catalyst for the oxidation of α-pinene to verbenone. The catalysts were analyzed using X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) surface area techniques, X-ray photoelectron spectroscopy (XPS), and ammonia temperature programmed reduction (NH3-TPD). Scanning electron microscopy (SEM), X-ray energy spectrometry (EDS), inductively coupled plasma emission spectroscopy (ICP-OES), Fourier infrared spectroscopy (FT-IR), and ultraviolet-visible spectroscopy (UV-vis) were performed to characterize the material. The effects of reaction temperature, reaction time, n(α-pinene)/n(TBHP), and solvent on the catalytic performance of CuAPO-5 were investigated. The results show that all the prepared catalysts have AFI topology and a large specific surface area. Copper is evenly distributed in the skeleton in a bivalent form. The introduction of copper increases the acid content of the catalyst. Under the optimized reaction conditions, 96.8% conversion of α-pinene and 46.4% selectivity to verbenone were achieved by CuAPO-5(0.06) molecular sieve within a reaction time of 12 h. CuAPO-5(0.06) can be recycled for five cycles without losing the conversion of α-pinene and the selectivity to verbenone. [ABSTRACT FROM AUTHOR]

A simple and convenient procedure for the γ, β-dimerization of verbenone was developed. The dimer was obtained during aging with KOH without a solvent. The process proceeds as the formation of the extended enolate of verbenone and its Michael addition to other molecules of verbenone. The product yield was 82% after purification by column chromatography and recrystallization.

The diamondback moth is a detrimental insect pest of brassicaceous crops which was among the first crop insects to be reported as DDT resistant. It has since proven to be significantly resistant to nearly every synthetic insecticide used in the field in many crucifer-producing regions. Due to insecticide control failures in some parts of the world, economically viable crucifer production is now all but impossible. As a result, there has been an increasing effort to identify new compounds with strong pesticidal activity. Cantharidin is one such compound that has been shown to be highly effective against a variety of insect pests. However, its chemical synthesis and potential toxicity to non-target organisms have been a major source of concern. Herein, using rational design approaches, a new series of cantharidin-based verbenone derivatives were synthesized and evaluated for their insecticidal activities against the diamondback moth. Among different compounds screened, compounds 6a, 6h, 6i, and 6q emerged as the most potent compounds exhibiting 100% mortality at a concentration of 100 mg/L after four days. These compounds demonstrated a good anti-feeding effect against the diamondback moth on cabbage leaves. Subsequently, a 3D QSAR study was carried out to identify the key structural features of the synthesized compounds and their correlation with insecticidal activity.

Verbenone and carvone are allylic monoterpenoid ketones with many applications in the fine chemicals industry that can be obtained, respectively, from the allylic oxidation of α-pinene and limonene over a silica-supported iron hexadecachlorinated phthalocyanine (FePcCl16-NH2-SiO2) catalyst and with t-butyl hydroperoxide (TBHP) as oxidant. As there are no reported analyses of the environmental impacts associated with catalytic transformation of terpenes into value-added products that include the steps associated with synthesis of the catalyst and several options of raw materials in the process, this contribution reports the evaluation of the environmental impacts in the conceptual process to produce verbenone and carvone considering two scenarios (SI-raw-oils and SII-purified-oils). The impact categories were evaluated using ReCiPe and IPCC methods implemented in SimaPro 9.3 software. The environmental impacts in the synthesis of the heterogeneous catalyst FePcCl16-NH2-SiO2 showed that the highest burdens in terms of environmental impact come from the use of fossil fuel energy sources and solvents, which primarily affect human health. The most significant environmental impacts associated with carvone and verbenone production are global warming and fine particulate matter formation, with fewer environmental impacts associated with the process that starts directly from turpentine and orange oils (SI-raw-oils) instead of the previously extracted α-pinene and limonene (SII-purified-oils). As TBHP was identified as a hotspot in the production process of verbenone and carvone, it is necessary to choose a more environmentally friendly and energy-efficient oxidizing agent for the oxidation of turpentine and orange oils. [ABSTRACT FROM AUTHOR]

Dracocephalum kotschyi Boiss. belongs to the family Lamiaceae, a perennial herbaceous medicinal plant that is native to Iran and is considered an endangered species. In-vitro plantlets (seven populations) were raised in MS medium supplemented with 0.1 mg/l BAP and 0.01 mg/l NAA and the rooted plantlets were acclimatized successfully under greenhouse conditions. In-vivo plants (eight populations) were propagated under greenhouse condition. The essential oils were isolated by hydro distillation and identification of chemical compounds was done by a combination of capillary GC and GCMS instruments. Twenty-five and forty compounds were identified in the different populations of in-vitro plantlet and in-vivo plant constituting 85.8%-99.68% and 85.1%- 95.06% of essential oils, respectively. The major components of in-vitro plantlet on different populations were Verbenone (2.5%-82.47%), Geranyl acetate (28.35%-62.07%), Methyl geranate (0.98%-79.06%), Neral (0.64%-3.13%), Geranial (4.93%-14.39%), Limonene (0.37%-10.36%) and E-Anethole (7.62%-20.71%). The composition of essential oil from greenhouse plant populations were dominated by Neral (11.24%-74.80%), Limonene (0.17%-25.26%), Geraniol (0.54%-40.81%), Geranial (0.04%-9.15%), Methyl geranate (0.16%-28.48%), E-Anethole (0 %-0.1%) and Verbenone (0.39%-23.96%). The highest values of Neral, Limonene and Geraniol percentage were obtained from greenhouse conditions. In contrast, the maximum values of Verbenone, Geranyl acetate, Methyl geranate, Geranial, and E-Anethole were observed in the essential oils of in-vitro plantlets. This study demonstrated difference of chemical composition between in-vitro plantlets and greenhouse plants of different populations on D. kotschyi species. Also, new chemotypes of D. kotschyi has been introduced for further research. [ABSTRACT FROM AUTHOR]

• Hybrid compounds combining the isoxazoline and thiazolidinone cores have been synthesized and characterized by different spectroscopic techniques. • A density functional theory (DFT) analysis was conducted on the synthesized compounds. • In vitro cytotoxicity assessments were performed against MDA-MB-231 and A-549 cancer cell lines. • in silico studies were carried out to elucidate the interaction mechanisms between the synthesized compounds and various enzymes. Hybrid compounds featuring isoxazole and thiazolidinone nuclei, alongside verbenone, have become pivotal in pharmacological research due to their versatile properties and straightforward synthesis methods. In this study, the hybrid compounds 3 – 5 were thoroughly analyzed using high-resolution mass spectrometry (HRMS) and 1H- and 13C NMR spectroscopy, confirming the presence of the isoxazoline and thiazolidinone cores. Additionally, text of in vitro cytotoxicity, computational molecular docking and dynamics studies were performed to study the cytotoxic profile and the modes of possible interactions between the synthesized compounds and the biological targets. The cytotoxicity test indicated that product 5 exhibited the highest activity, with IC 50 values ranging from 25.87±3.21 to 28.12±3.54 µM against MDA-MB-231 and A-549 cancer cell lines. From a theoretical point of view, the comparative analysis of compounds 3–5 against the references in the in silico study revealed significant interactions for these compounds with the isoenzymes of alkaline phosphatase and carbonic anhydrase. [Display omitted] [ABSTRACT FROM AUTHOR]

HS-SPME-GC–MS analysis of the scent of Dactylorhiza viridis revealed the presence of verbenone (28.86%), caryophyllene (25.67%), β-terpineol (9.48%), and δ-cadinene (6.94%). In the scent of Dactylorhiza romana β-ocimene (18.69%), pentadecane (18.40%), α-farnesene (14.65%), and isopropyl 14-methylpentadecanoate (14.32%) were found. Dactylorhiza incarnata contained tetradecane (11.07%), pentadecane (28.40%), hexadecane (19.53%), heptadecane (17.33%), and α-cubenene (11.48%). Analysis of Dactylorhiza saccifera showed the presence of caryophyllene (17.38%), pentadecane (6.43%), hexadecane (6.13%), and heptadecane (5.08%). Finally, the aroma components found in Dactylorhiza sambucina were caryophyllene (12.90%), β-sesquiphellandrene (32.16%), 4,5-di-epi-aristolochene (10.18%). [ABSTRACT FROM AUTHOR]

Tagetes parryi is a plant empirically used to treat gastrointestinal and inflammatory diseases, its essential oil (EOTP) was obtained from the aerial parts, and the composition was elucidated by GC-MS. The in vivo and in vitro anti-inflammatory activities and the antinociceptive activity of EOTP and (1S)-(-)-verbenone (VERB) were assessed. The major compounds identified for EOTP were verbenone (33.39%), dihydrotagetone (26.88%), and tagetone (20.8%). EOTP and VERB diminished the ear oedema induced with TPA by 93.77 % and 81.13 %, respectively. EOTP and VERB decreased inflammation in a 12-O-tetradecanoylphorbol-13-acetate (TPA) chronic model with ED50 = 54.95 mg/kg and 45.24 mg/kg, respectively. EOTP (15 µg/mL) inhibited the in vitro production of the pro-inflammatory mediators NO (67.02%), TNF-α (69.21%), and IL-6 (58.44%) in LPS-stimulated macrophages. In the acetic induced writhing test, EOTP and VERB showed antinociceptive effects with ED50 = 84.93 mg/kg and ED50 = 45.24 mg/kg, respectively. In phase 1 of the formalin test, EOTP and VERB showed no antinociceptive effects, whereas in phase 2, EOTP (ED50 = 35.45 mg/kg) and VERB (ED50 = 24.84 mg/kg) showed antinociceptive effects. The antinociceptive actions of ETOP and VERB were blocked with the co-administration of L-NAME. This study suggests that EOTP and VERB might be used in the treatment of pain and inflammatory problems. [ABSTRACT FROM AUTHOR]

A series of novel (−)-verbenone hydrazones was designed and synthesized via condensation of terpenoid with hydrazides derived from phenoxyacetic acid. The structure of target compounds was confirmed by 1H-NMR and 13C-NMR analysis, Raman and FT-IR spectroscopy, electrospray ionization method and fast atom bombardment (FAB) mass spectrometry. Thermal properties of (−)-verbenone hydrazones 3a–3e were estimated by differential scanning calorimetry and their purity by HPLC coupled to mass spectrometry. Verbenone hydrazones were revealed to exist as Z/E geometrical isomers about C═N bond and cis/trans amide conformers. Verbenone derivatives were estimated as potential anticonvulsant agents after their oral administration against pentylenetetrazole and maximal electroshock-induced seizures in mice. Analgesic effect of hydrazones was studied by topical application on models of allyl isothiocyanate and capsaicin-induced pain. The present findings indicate that verbenone hydrazones contribute to seizure protection both at short (6 h) and long (24 h) time periods by blocking chemical- and electroshock-induced convulsions. Binding of compounds 3a–3e to TRPA1/TRPV1 ion channels was suggested as a feasible mechanism explaining their significant analgesic activity.

This study was carried out to evaluate the in vitro antioxidant activity and the chemical composition of essential oils and organic extracts of Moroccan Tetraclinis articulata cones (Khemisset region). The GC-MS analysis of essential oils identified a total 23 volatile components. The major constituents of the oil were α-pinene (18.33%), cis-verbenone (10.02%), and L-pinocarveol (8. 32%). For phytosterols analysis of hexane extract, β-sitosterol constitutes the majority with a percentage of 77.74%. The amount of total phenolic and flavonoid contents was high in the methanol extract (78.54±2.8 mg GAE / g and 41.11± 4.5 mg QE/g, respectively) and the Antioxidant capacity determined by DPPH method showed a strongest radical scavenging activity exhibition by the methanol extract (IC50=0.038±0.006 mg/mL). The results indicated that T. articulata contains bioactive compounds which are responsible for its antioxidant activity. Therefore, this plant could be potential candidates for the preparation of a natural antioxidant drug or an additive preparation. [ABSTRACT FROM AUTHOR]

The ambrosia beetle Xylosandrus germanus (Blandford) is an invasive pest that has caused tree decline and death in numerous NY dwarf apple orchards during the past ten years, despite efforts to control them using trunk sprays of chlorpyrifos or pyrethroids, either alone or combined with the repellent verbenone. From 2017 to 2019, we tested trunk applications of different repellents and plant defense compounds for protection against X. germanus in potted apple trees adjacent to infested orchards. Treatments included topical formulations of verbenone and methyl salicylate (MeSa), alone and in combination, at different rates and timings. Additional treatments evaluated included the systemic acquired resistance activators acibenzolar-S-methyl, Reynoutria sachalinensis extract, and salicylic acid. The combination verbenone+MeSa treatments had the lowest incidences of attack sites and galleries containing adults or brood, although results varied among years. In a separate trial, we found no significant difference in numbers of adults caught in ethanol-baited traps placed 5–20 m from an apple bolt treated with the verbenone+MeSa repellent, suggesting that the repellent's effect did not extend to those distances from the treated target. Cross-sectional discs of trunk tissue sampled in August were analyzed for levels of phytohormones. Quantities of ergosterol, abscissic acid, salicylic acid, jasmonic acid, methyl salicylate, methyl jasmonate, trans-cinnamic acid, and indole-3-cinnamic acid did not significantly vary across treatments; however, trees with greater beetle damage contained higher levels of jasmonic and salicylic acid, which are key molecules in plant defense pathways. [ABSTRACT FROM AUTHOR]

The polyphagous shot hole borer (PSHB), Euwallacea fornicatus (Eichhoff), is an ambrosia beetle (Coleoptera: Curculionidae) infesting avocado branches Persea americana Mill. in North America, South Africa and Israel. Field experiments were conducted with attractive quercivorol traps and repellents on trees to develop push–pull control methods. PSHBs were collected over the summer from multiple-funnel traps baited with quercivorol in grids of low-, medium- and high-density traps to assess mass trapping interactions and capture trends. Mean catch/trap-week was higher on peripheral outer traps compared to the next inner ring of traps in grids. These ratios and grids were simulated to estimate the circular effective attraction radius (EARc) of multiple-funnel traps and compared to a previous relationship for sticky traps yielding EARc from release rate of quercivorol. The results indicate that multiple-funnel traps have smaller EARc in higher-density grids, likely due to interactions between traps. Tests with verbenone compared to methyl salicylate (MeSA) indicate both are repellents and no evidence for synergism. Dollops of verbenone–MeSA–SPLAT (5% each volatile) were applied monthly at 10- and 40-cm spacings along branched trunks of avocado trees, with release of volatiles declining exponentially over a month. These treatments caused a reduction in both numbers of aggregations/tree and attacks/aggregation to about half that of untreated control trees. Verbenone–MeSA–SPLAT dollops caused localized phytotoxicity on avocado bark, suggesting 8 cm2 plastic bag dispensers containing 0.25 g verbenone are preferred at 40-cm spacing. Push–pull should be done just before flight season to overwhelm natural attraction of single females initiating aggregations. [ABSTRACT FROM AUTHOR]

Tagetes parryi is a plant empirically used to treat gastrointestinal and inflammatory diseases, its essential oil (EOTP) was obtained from the aerial parts, and the composition was elucidated by GC-MS. The in vivo and in vitro anti-inflammatory activities and the antinociceptive activity of EOTP and (1S)-(-)-verbenone (VERB) were assessed. The major compounds identified for EOTP were verbenone (33.39%), dihydrotagetone (26.88%), and tagetone (20.8%). EOTP and VERB diminished the ear oedema induced with TPA by 93.77 % and 81.13 %, respectively. EOTP and VERB decreased inflammation in a 12-O-tetradecanoylphorbol-13-acetate (TPA) chronic model with ED50 = 54.95 mg/kg and 45.24 mg/kg, respectively. EOTP (15 µg/mL) inhibited the in vitro production of the pro-inflammatory mediators NO (67.02%), TNF-α (69.21%), and IL-6 (58.44%) in LPS-stimulated macrophages. In the acetic induced writhing test, EOTP and VERB showed antinociceptive effects with ED50 = 84.93 mg/kg and ED50 = 45.24 mg/kg, respectively. In phase 1 of the formalin test, EOTP and VERB showed no antinociceptive effects, whereas in phase 2, EOTP (ED50 = 35.45 mg/kg) and VERB (ED50 = 24.84 mg/kg) showed antinociceptive effects. The antinociceptive actions of ETOP and VERB were blocked with the co-administration of L-NAME. This study suggests that EOTP and VERB might be used in the treatment of pain and inflammatory problems.

Euwallacea fornicatus (Eichhoff), the polyphagous shot hole borer (PSHB), is an ambrosia beetle infesting avocado Persea americana Mill. limbs in North America and Israel. We conducted field experiments with sticky traps in avocado orchards to develop push–pull semiochemical methods of managing PSHB. Traps baited with 10-fold increasing doses (0.01 to 100× or 1.26 µg to 12.6 mg/d) of attractant quercivorol were previously shown to increasingly capture female PSHB (males flightless). We converted trap catch of this relationship to a standardized effective attraction radius (EAR) that predicts capture power of baited-traps regardless of insect flight density. Earlier, piperitone and verbenone were shown to strongly inhibit attraction of PSHB to quercivorol-traps. We tested increasing numbers of 1× piperitone dispensers at 0.75-m distance surrounding a quercivorol-trap and found PSHB catch to decline exponentially. Increasing decadic doses (0.01 to 10×) of either verbenone or piperitone released at 1× quercivorol-traps caused a sigmoidal first-order kinetic-decay in catch. Verbenone (1×) placed at increasing distances (0, 0.25, 0.5, 1, and 2 m) from a 1× quercivorol-trap became increasingly ineffective in reducing catch of PSHB. We found no evidence that ethanol released from 7.5 to 480 mg/d affected attraction of PSHB, but Scobicia chevrieri (Villa and Villa) (Coleoptera: Bostrichidae) was increasingly attracted. Due to their relatively short-range (<0.5 m) inhibition of attractive sources, piperitone, and verbenone dispensers should be placed on avocado trunks where PSHB aggregations occur before the flight season. [ABSTRACT FROM AUTHOR]

The protection of high-value trees against bark beetles and the development of alternatives to bole sprays is a priority for the tree manager. The objective of this study was to evaluate stem-injected TREE-äge® (emamectin benzoate [EB]) as a protective treatment for western white pines (Pinus monticola Dougl. ex D. Don) against mountain pine beetle (MPB, Dendroctonus ponderosae Hopkins). Treatment efficacy was based solely on tree mortality as per Shea protocols (i.e., ≥ 60% check vs. ≤ 20% treated tree mortality). Our first experiment was installed in 2007 and included trees stem-injected with TREE-äge and untreated controls. Bole application of S-(-)-verbenone and green leaf volatile (GLV) blend was included for observational comparison. Pressure from MPB was heavy, as indicated by the number and timing of control tree mortality (90%). Strip attacks by MPB in TREE-äge trees indicated that the impacts of EB, and by inference its distribution, were inconsistent. In 2009, the injection protocol was revised to improve EB distribution in the phloem via closer injection points. In the 2009 TREE-äge-treated trees, adult beetle mining stopped when they contacted phloem and was insufficient to cause tree death by girdling. Blue-stain fungi colonized the sapwood of trees in both studies. Isolates from autopsied trees treated with TREE-äge alone were subsequently identified as Grosmannia clavigera and Leptographium longiclavatum (Ophiostomatales: Ascomycota), species that can incite tree mortality. In 2013, we revised our protocol to include GLV plus verbenone or propiconazole with TREE-äge, wherein these treatments proved effective in protecting trees against MPB and their associated pathogenic fungi. [ABSTRACT FROM AUTHOR]

Laurel wilt is a disease that has caused extensive mortality of redbay Persea borbonia in the southeastern U.S.A. The redbay ambrosia beetle Xyleborus glabratus is the vector of the causal agent of laurel wilt, the fungus Raffaelea lauricola.We tested two potential repellents to the redbay ambrosia beetle, verbenone and methyl salicylate (MeSA) in an 8‐month large‐scale experiment conducted in three locations in Florida. In each location, redbay trees were treated with a single or double application of SPLAT (Specialized Pheromone and Lure Application Technology; ISCA Technologies, Riverside, California) verbenone, as well as SPLAT with a 1:2 mix of MeSA and verbenone.The MeSA + verbenone mixes did not reduce beetle captures compared with the control treatment, whereas SPLAT verbenone alone significantly reduced the number of beetles captured on sticky traps placed on redbay trees in the three locations. The reduction of beetle capture was similar regardless of one or two treatments of SPLAT verbenone. The reduction of tree death with the SPLAT verbenone treatment was not statistically significant.The results of the present study suggest that trunk application of verbenone can reduce landing rates of the redbay ambrosia beetle on live redbay trees and shows promise for use in an integrated pest management strategy against laurel wilt. [ABSTRACT FROM AUTHOR]

The Chinese white pine beetle, Dendroctonus armandi Tsai and Li is a native species of bark beetle and one of the most destructive in much of western China. Little is known about the characterization of the pheromones trans-verbenol and verbenone, and their functions in D. armandi are unknown. Electroantennogram tests (EAG) and olfactory assays (Y-tube assays) in the laboratory revealed that (1) trans-verbenol may be an anti-aggregation pheromone for male and an aggregation pheromone for female D. armandi and (2) female beetles are more attracted to controls (hexane) than low concentrations of verbenone and male beetles more attracted to controls than high concentrations of verbenone. Field trials indicated that the addition of verbenone to bait used to trap D. armandi remarkably decreased the efficiency of field trapping. These results indicate that verbenone is an anti-aggregation pheromone for male D. armandi. This research provides evidence of the role of verbenone among the different types of pheromones. The pheromone verbenone clearly could be used to protect healthy Chinese white pines.

Olfactory systems are indispensable for insects as they, including Western Flower Thrips ( Frankliniella occidentalis ), use olfactory cues for ovipositing and feeding. F. occidentalis use odorant binding proteins (OBPs) to transport semiochemicals to odorant receptors to induce a behavioural response from the sensillum lymph of the insect's antennae. This study identifies four OBPs of F. occidentalis and analyses their expression at three stages of growth: larvae, adult males and adult females. Further, it investigates the presence of conserved motifs and their phylogenetic relationship to other insect species. Moreover, FoccOBP3 was in silico characterized to analyse its structure along with molecular docking and molecular dynamics simulations to understand its binding with semiochemicals of F. occidentalis . Molecular docking revealed the interactions of methyl isonicotinate, p-anisaldehyde and (S)-(-)-verbenone with FoccOBP3 . Moreover, molecular dynamics simulations showed bonding stability of these ligands with FoccOBP3, and field trials validated that Lurem TR (commercial product) and p-anisaldehyde had greater attraction as compared to (S)-(-)-verbenone, given the compound's binding with FoccOBP3 . The current study helps in understanding the tertiary structure and interaction of FoccOBP3 with lures using computational and field data and will help in the identification of novel lures of insects in the future, given the importance of binding with OBPs.Communicated by Ramaswamy H. Sarma.

Copyright of Chemistry & Industry of Forest Products is the property of Chemistry & Industry of Forest Products Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Non‐native ambrosia beetles (Coleoptera: Curculionidae), especially Xylosandrus compactus (Eichhoff), Xylosandrus crassiusculus (Motschulsky) and Xylosandrus germanus (Blandford), are destructive wood‐boring pests of trees in ornamental nurseries and tree fruit orchards. Previous studies have demonstrated the adults are repelled by verbenone and strongly attracted to ethanol. We tested a "push–pull" semiochemical strategy in Ohio, Virginia and Mississippi using verbenone emitters to "push" beetles away from vulnerable trees and ethanol lures to "pull" them into annihilative traps. Container‐grown trees were flood‐stressed to induce ambrosia beetle attacks and then deployed in the presence or absence of verbenone emitters and a perimeter of ethanol‐baited interception traps to achieve the following treatment combinations: (a) untreated control, (b) verbenone only, (c) ethanol only, and (d) verbenone plus ethanol. Verbenone and ethanol did not interact to reduce attacks on the flooded trees, nor did verbenone alone reduce attacks. The ethanol‐baited traps intercepted enough beetles to reduce attacks on trees deployed in Virginia and Mississippi in 2016, but not in 2017, or in Ohio in 2016. Xylosandrus germanus, X. crassiusculus and both Hypothenemus dissimilis Zimmermann and X. crassiusculus were among the predominant species collected in ethanol‐baited traps deployed in Ohio, Virginia and Mississippi, respectively. Xylosandrus germanus and X. crassiusculus were also the predominant species dissected from trees deployed in Ohio and Virginia, respectively. While the ethanol‐baited traps showed promise for helping to protect trees by intercepting ambrosia beetles, the repellent "push" component (i.e., verbenone) and attractant "pull" component (i.e., ethanol) will need to be further optimized in order to implement a "push–pull" semiochemical strategy. [ABSTRACT FROM AUTHOR]

This work demonstrates how a series of complex, chiral cyclobutane derivatives can be accessed in four steps from the terpene verbenone through the application of a directed C−H functionalization approach. The developed synthetic route involved an 8‐aminoquinoline‐directed C(sp3)−H arylation as the key step, and this reaction could be carried out with a wide range of aryl and heteroaryl iodides to furnish a variety of cyclobutane products with three contiguous stereocenters. Moreover, it was shown that the 8‐aminoquinoline auxiliary could be effectively removed from the cyclobutane derivatives using an ozonolysis‐based cleavage method. Three in a row: A short synthetic route to chiral and structurally elaborate cyclobutanes with three contiguous stereocenters from the terpene verbenone is presented. In the key step, a highly efficient directing‐group‐assisted C(sp3)−H arylation was used to install a wide range of aryl and heteroaryl substituents with excellent stereocontrol. Removal of the 8‐aminoquinoline directing group from these compounds was demonstrated using an ozonolysis‐based cleavage method. [ABSTRACT FROM AUTHOR]

Two pine shoot beetles, Tomicus yunnanensis and Tomicus minor, are the most destructive pests of Pinus yunnanensis in southwestern China. We investigated behavioral responses within and between these two species during the shoot-feeding phase using walking bioassays. We also identified the pheromonal aspects of beetles by static solid phase microextraction (SPME) and hindgut extraction following interactive communication by gas chromatography-mass spectroscopy (GC-MS). Both species were significantly attracted by their own species and the same sex, and attraction was inhibited by exposure to additional beetles or to the hindgut extracts of beetles which had shown interaction. Female and male T. minor and T. yunnanensis hindguts contained 0.19, 0.09, 0.22, and 0.05 ng/individual of (−)-trans-verbenol, respectively; following interaction with additional beetles, this increased to 16.74–292.71 ng/individual in T. minor females. Mean concentration of verbenone detected in the hindguts of female/male individuals of T. minor and T. yunnanensis under natural conditions were 0.16, 0.06, 0.03, and 0.05 ng/individual, respectively, but these correspondingly increased to 5.90, 2.43, 0.06, and 0.19 ng/individual after exposure to additional insects. In T. yunnanensis, the amounts of detectable (−)-trans-verbenol and verbenone extracted from hindguts were lower than those from T. minor. The levels of cis-verbenol and (−)-trans-verbenol most attractive to walking T. yunnanensis and T. minor were 0.1 and 1.0 ng/μl, respectively. Verbenone was not attractive at any of the concentrations tested. The addition of verbenone to cis-verbenol or (−)-trans-verbenol reduced the attraction responses. We conclude that the (−)-trans-verbenol produced by these two pine shoot beetles is attractive at low concentrations and repellant at high concentrations, thereby fostering intraspecific competition. Verbenone is produced to prevent overcrowding via interspecific inhibition, and to expel beetles during shoot-feeding. [ABSTRACT FROM AUTHOR]

• CDs maintain their recognition ability towards aromas in DES:water mixtures. • Water vs DES:water: Same stoichiometry lower stability of inclusion complexes. • Water vs DES:water: Similar inclusion mechanism. The use of cyclodextrins (CDs) in combination with deep eutectic solvents (DESs) is nowadays an emerging and promising strategy for the solvation of hydrophobic compounds, such as aromas. This approach combines the solvation efficiency of the solvent bulk and the complexation ability of CDs. However, literature lacks information about the complexation mechanism in CDs in these non-conventional solvents. Hence, this study aims to elucidate such mechanism by investigating the complexation behavior and the binding ability of β-CD and α-CD towards verbenone and camphor, respectively, in choline chloride:urea DES:water (70:30 wt%) mixture. First, the formation constants (K f) of the chosen model inclusion complexes were determined by static headspace-gas chromatography (SH-GC). Then, the formation of inclusion complexes was demonstrated by 1H 2D DOSY and 2D ROESY NMR studies. Finally, isothermal titration calorimetry (ITC) experiments were carried out, for the first time in a DES:water mixture, in order to evaluate the thermodynamic parameters of the inclusion phenomenon. Altogether, results proved the formation of stable inclusion complexes in the new non-conventional medium constituted of choline chloride:urea DES:water (70:30 wt%). Interestingly, the thermodynamic signatures and the stoichiometries of interactions were similar between water and choline chloride:urea DES:water (70:30 wt%). In particular, the present study of the α-CD/camphor system constitutes the first report of a 2:1 complex in a DES:water mixture. [ABSTRACT FROM AUTHOR]

The work presents research on the synthesis of carbon catalysts from pine cones and their application in the oxidation of α-pinene. The preparation of carbon catalysts involved chemical activation with an aqueous potassium hydroxide solution and carbonization of the obtained precursor. The pine cones carbonization was performed for 1 h at the temperatures range from 700° to 1000°C in an inert gas atmosphere (N 2). Characterizations of the activated carbons were performed with the following instrumental analyses: XRD, SEM, and XPS. No solvent was used in the oxidation studies, and molecular oxygen was the oxidizing agent. The effects of three parameters – temperature, amount of the carbon catalyst, and reaction time – on the values of conversion of α-pinene, as well as the product selectivities, were investigated. It was shown that it is most advantageous to perform the oxidation of α-pinene at 100 °C for 1 h with the PC_850 catalyst (so-named for the temperature of its carbonization process, 850 °C), whose content in the reaction mixture is 0.5 wt%. Under these conditions, the conversion of α-pinene amounted to 41 mol%. Moreover, the selectivities of the three main products were: α-pinene oxide (28 mol%), verbenol (16 mol%), and verbenone (13 mol%). In addition to these products, other valuable compounds, such as campholenic aldehyde, pinocarveol, myrtenal, myrtenol, carveol, carvone, and pinanediol were also produced. [Display omitted] • New concept of sustainable and ecological technology of organic syntheses. • Carbon catalysts from pine cones are efficient catalysts for α-pinene oxidation with oxygen. • Cost-effective and energy-efficient process even at low temperatures. • Mild optimal conditions: 41% conversion after 1 h at 110 °C and for 0.5 wt% catalyst. • α-Pinene oxide, verbenol, and verbenone are main products with 28%, 16% and 13% respective selectivities. [ABSTRACT FROM AUTHOR]

Since its introduction from North America, Dendroctonus valens LeConte has become a destructive forest pest in China. Although gut aerobic bacteria have been investigated and some are implicated in beetle pheromone production, little is known about the abundance and significance of facultative anaerobic bacteria in beetle gut, especially with regards to effects of oxygen on their role in pheromone production. In this study, we isolated and identified gut bacteria of D. valens adults in an anaerobic environment, and further compared their ability to convert cis-verbenol into verbenone (a multi-functional pheromone of D. valens) under different O2 concentrations. Pantoea conspicua, Enterobacter xiangfangensis, Staphylococcus warneri were the most frequently isolated species among the total of 10 species identified from beetle gut in anaerobic conditions. Among all isolated species, nine were capable of cis-verbenol to verbenone conversion, and the conversion efficiency increased with increased oxygen concentration. This O2-mediated conversion of cis-verbenol to verbenone suggests that gut facultative anaerobes of D. valens might play an important role in the frass, where there is higher exposure to oxygen, hence the higher verbenone production. This claim is further supported by distinctly differential oxygen concentrations between gut and frass of D. valens females.

In three study sites in the Michoacan State, Mexico, we tested five behavioral chemicals: Pityol, 4 Allylanisole, Verbenone (3M MEC), Conophthorin and Hexenol, in several field trials mixed at six combinations or treatments as posible repelents for females of Conophthorus conicolens W and Conophthorus teocotum W. Beetle-host tree combinations included these two cone bores species on cones of Pinus pseudostrobus (Lidl), the first, and on Pinus teocote (Schl and Cham) the second ones, baited previously with five semiochemicals, including the only case of Verbenone (3 M Mec) which was sprayed alone on healthy green cones of second year growing free from the presence of cone borers and previously to fly period of scolitids as at all other treatments. Cones baited with the combination of semiochemicals P+4AA+V besides these sprayed with Verbenone were less attacked and obviously distinctibily. Moreover, cones baited only with Pityol and adding Verbenone as a spray periodically, the effect of treatment was inefficient to protect them from boring by Conophthorus conicolens W, whereas these baited with P+4AA synergized the presence of cone borer females; The combination of all these semiochemicals and added with Conophthorin (P+4AA+C) and Hexenol (P+4AA+H) had inconsistent results, although for this last case, Hexenol apparently was synergist when is mixed with Pityol and 4AA , to prevent from attack by Conophthorus teocotum W. The best results of study subject were obtained with the combined treatment Pityol +4AA+Verbenone, and significately better spraying as alone as Verbenone and repelling C. conicolens W and C. teocotum W.