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It has been a quarter century since salicylic acid methyltransferase, the founding member of the plant SABATH enzyme family, was discovered. From making methyl benzoate to synthesizing caffeine, from modulating auxins and gibberellins to participating in strigolactone biosynthesis, new biochemical functions of SABATH methyltransferases have continuously been revealed, with more than 20 substrates of diverse structures identified. Three-dimensional structures for several members of the SABATH family have been solved, rendering explanations of reaction mechanism and structural basis of substrate specificity. The biological functions of several SABATH genes from diverse plants were elucidated by analyzing transgenic plants with overexpression, reduced expression or knock-out mutants of respective SABATH genes. In the majority of sequenced plants examined, SABATH genes constitute a medium-sized family. Diverse catalytic functions of SABATHs have evolved largely via gene duplication followed by functional divergence. Some SABATH family members have a deep evolutionary origin; some others, while catalyzing an identical reaction, evolved more than once. Equally important, many members acquired lineage-specific functions. All these are indicative of the important contributions of the SABATH family to land plant evolution and adaptation. [ABSTRACT FROM AUTHOR]

The impact of aluminum trialkyl (AlR3) and esters/silane-external electron donor (EED) on the activity and reaction kinetics of ZN catalyst (TiC14//MgCl2—ethyl benzoate/diisobutyl phthalate) in propylene polymerization was studied. The polymerization kinetic was studied for different types of catalysts with various types of EEDs. To correlate the kinetic behavior of propylene polymerization and various reactions taking place during the polymerization, we have studied in situ interactions of EEDs with co-catalyst by FT-NMR. The used EEDs are (1) p-isopropoxy methyl benzoate (PIPMB), (2) diphenyldimethoxy silane (DPDMS) and (3) mixture of isopropyl myristate (IPM) and (DPDMS) were interacted with triethyl aluminum (TEAl) at defined molar ratios. In the diester type of catalyst, two types of kinetic profile were observed with two different types of EED systems. Initially very fast polymerization kinetic was observed when only silane type of EED was used during polymerization which became steady with mixed EED (Silane + Aliphatic Ester). This EED system shows steady-state and controllable kinetic characteristics due to mixing of IPM with silane. The study by FT-NMR spectroscopy indicated the formation of the new compounds that are inhibiting the rate of polymerization reaction. The compounds, such as ketones and alcohols, are responsible for controlling the rate of polymerization reaction. The contribution of each of these product formations during processes depends on the catalyst composition and on the polymerization conditions. [ABSTRACT FROM AUTHOR]

Tunable‐lifetime room‐temperature phosphorescence (RTP) materials have been widely studied due to their broad applications. However, only few reports have achieved wide‐range lifetime modulation. In this work, ultra‐wide range tunable‐lifetime efficient dark blue RTP materials were realized by doping methyl benzoate derivatives into polyvinyl alcohol (PVA) matrix. The phosphorescence lifetimes of the doped films can be increased from 32.8 ms to 1925.8 ms. Such wide range of phosphorescence lifetime modulation is extremely rare in current reports. Moreover, the phosphorescence emission of the methyl 4‐hydroxybenzoate‐doped film is located in the dark blue region and the phosphorescence quantum yield reaches as high as 15.4 %, which broadens their applications in organic optoelectronic information. Further studies demonstrated that the reason for the tunable lifetime was that the magnitude of the electron‐donating ability of the substituent group modulates the HOMO–LUMO and singlet‐triplet energy gap of methyl benzoate derivatives, as well as the ability to non‐covalent interactions with PVA. Moreover, the potential applications of luminescent displays and optical anti‐counterfeiting of these high‐performance dark blue RTP materials have been conducted. [ABSTRACT FROM AUTHOR]

Tunable‐lifetime room‐temperature phosphorescence (RTP) materials have been widely studied due to their broad applications. However, only few reports have achieved wide‐range lifetime modulation. In this work, ultra‐wide range tunable‐lifetime efficient dark blue RTP materials were realized by doping methyl benzoate derivatives into polyvinyl alcohol (PVA) matrix. The phosphorescence lifetimes of the doped films can be increased from 32.8 ms to 1925.8 ms. Such wide range of phosphorescence lifetime modulation is extremely rare in current reports. Moreover, the phosphorescence emission of the methyl 4‐hydroxybenzoate‐doped film is located in the dark blue region and the phosphorescence quantum yield reaches as high as 15.4 %, which broadens their applications in organic optoelectronic information. Further studies demonstrated that the reason for the tunable lifetime was that the magnitude of the electron‐donating ability of the substituent group modulates the HOMO–LUMO and singlet‐triplet energy gap of methyl benzoate derivatives, as well as the ability to non‐covalent interactions with PVA. Moreover, the potential applications of luminescent displays and optical anti‐counterfeiting of these high‐performance dark blue RTP materials have been conducted. [ABSTRACT FROM AUTHOR]

A series of potasium boasted phosphomolybdic acid (PM) catalysts were successfully synthesized by ion-exchange method. These materials were characterized by BET surface area, FT-IR, XRD, Pyridine adsorbed FT-IR and TEM analysis to find the structural and nature of acidic sites of the catalyst. BET surface area result reveals that surface area significantly improved after K loadings compare to pure phosphomolybdic acid. XRD results provide crystallites of cubic Keggin ion were observed after K loading. FT-IR results provide characteristic Keggin ion bands were retained even after K loadings. TEM analysis reveals spherical morphology is maintained even after K loadings and KPM-2 catalyst exhibits smaller particle size than other K loadings. Pyridine adsorbed FT-IR spectra exhibits Brønsted to Lewis acidic sites ratio is higher in case of KPM-2 when compared to other K loadings. These synthesized K boasted PM materials were evaluated for oxidative esterification of benzyl alcohol to methyl benzoate possesses higher activity and selectivity during reaction than pure PM catalyst. [ABSTRACT FROM AUTHOR]

Upgrading of polyethylene terephthalate (PET) waste into valuable oxygenated molecules is a fascinating process, yet it remains challenging. Herein, we developed a two‐step strategy involving methanolysis of PET to dimethyl terephthalate (DMT), followed by hydrogenation of DMT to produce the high‐valued chemical methyl p‐methyl benzoate (MMB) using a fixed‐bed reactor and a Cu/ZrO2 catalyst. Interestingly, we discovered the phase structure of ZrO2 significantly regulates the selectivity of products. Cu supported on monoclinic ZrO2 (5 %Cu/m‐ZrO2) exhibits an exceptional selectivity of 86 % for conversion of DMT to MMB, while Cu supported on tetragonal ZrO2 (5 %Cu/t‐ZrO2) predominantly produces p‐xylene (PX) with selectivity of 75 %. The superior selectivity of MMB over Cu/m‐ZrO2 can be attributed to the weaker acid sites present on m‐ZrO2 compared to t‐ZrO2. This weak acidity of m‐ZrO2 leads to a moderate adsorption capability of MMB, and facilitating its desorption. Furthermore, DFT calculations reveal Cu/m‐ZrO2 catalyst shows a higher effective energy barrier for cleavage of second C−O bond compared to Cu/t‐ZrO2 catalyst; this distinction ensures the high selectivity of MMB. This catalyst not only presents an approach for upgrading of PET waste into fine chemicals but also offers a strategy for controlling the primary product in a multistep hydrogenation reaction. [ABSTRACT FROM AUTHOR]

Upgrading of polyethylene terephthalate (PET) waste into valuable oxygenated molecules is a fascinating process, yet it remains challenging. Herein, we developed a two‐step strategy involving methanolysis of PET to dimethyl terephthalate (DMT), followed by hydrogenation of DMT to produce the high‐valued chemical methyl p‐methyl benzoate (MMB) using a fixed‐bed reactor and a Cu/ZrO2 catalyst. Interestingly, we discovered the phase structure of ZrO2 significantly regulates the selectivity of products. Cu supported on monoclinic ZrO2 (5 %Cu/m‐ZrO2) exhibits an exceptional selectivity of 86 % for conversion of DMT to MMB, while Cu supported on tetragonal ZrO2 (5 %Cu/t‐ZrO2) predominantly produces p‐xylene (PX) with selectivity of 75 %. The superior selectivity of MMB over Cu/m‐ZrO2 can be attributed to the weaker acid sites present on m‐ZrO2 compared to t‐ZrO2. This weak acidity of m‐ZrO2 leads to a moderate adsorption capability of MMB, and facilitating its desorption. Furthermore, DFT calculations reveal Cu/m‐ZrO2 catalyst shows a higher effective energy barrier for cleavage of second C−O bond compared to Cu/t‐ZrO2 catalyst; this distinction ensures the high selectivity of MMB. This catalyst not only presents an approach for upgrading of PET waste into fine chemicals but also offers a strategy for controlling the primary product in a multistep hydrogenation reaction. [ABSTRACT FROM AUTHOR]

The crystal structures and Hirshfeld surface analyses of three similar azo compounds are reported. Methyl 4-{2,2-di­chloro-1-[(E)-phenyl­diazen­yl]ethen­yl}benzoate, C16H12Cl2N2O2, (I), and methyl 4-{2,2-di­chloro-1-[(E)-(4-methyl­phen­yl)diazen­yl]ethen­yl}benzoate, C17H14Cl2N2O2, (II), crystallize in the space group P21/c with Z = 4, and methyl 4-{2,2-di­chloro-1-[(E)-(3,4-di­methyl­phen­yl)diazen­yl]ethen­yl}benzoate, C18H16Cl2N2O2, (III), in the space group P with Z = 2. In the crystal of (I), mol­ecules are linked by C--H...N hydrogen bonds, forming chains with C(6) motifs parallel to the b axis. Short inter­molecular Cl...O contacts of 2.8421(16)Å and weak van der Waals inter­actions between these chains stabilize the crystal structure. In (II), mol­ecules are linked by C--H...O hydrogen bonds and C--Cl...π inter­actions, forming layers parallel to (010). Weak van der Waals inter­actions between these layers consolidate the mol­ecular packing. In (III), mol­ecules are linked by C--H...π and C--Cl...π inter­actions forming chains parallel to [011]. Furthermore, these chains are connected by C--Cl...π inter­actions parallel to the a axis, forming (0 1) layers. The stability of the mol­ecular packing is ensured by van der Waals forces between these layers. [ABSTRACT FROM AUTHOR]

In this study, benzohydroxamic acid molecules were synthesized from methyl 4‐amino‐2‐methoxy, methyl 4‐amino‐3‐nitro, methyl 4‐amino‐3‐methyl, and methyl 4‐amino‐3‐chloro benzoate molecules, and the horseradish peroxidase (HRP) enzyme was purified in one step using the affinity chromatography technique for the first time. The IC50 and Ki values for the 4‐amino 3‐methyl benzohydroxamic acid molecule were 0.136 and 0.132 ± 0.054 μM, respectively, while the IC50 and Ki values for the 4‐amino‐3‐nitro benzohydroxamic acid molecule were 56.00 and 51.90 ± 9.90 μM, respectively. It was found that the IC50 and Ki values for the 4‐amino‐3‐chloro benzohydroxamic acid molecule were 218.33 and 175.67 ± 43.78 μM, respectively, whereas the IC50 and Ki values for the 4‐amino‐2‐methoxy benzohydroxamic acid molecule were 306.00 and 218.00 ± 68.80 μM, respectively. The HRP enzyme was synthesized from 4‐amino‐2‐methoxy hydroxamic acid column with a 35.97% yield 601.13 times, 4‐amino‐3‐nitro hydroxamic acid column, with a 14.00% yield 404.11 times, 4‐amino‐3‐methyl hydroxamic acid column with an 8.70% yield 394.88 times, and 4‐amino‐3‐chloro hydroxamic acid column with a 4.48% yield 284.85 times. Thus, the HRP enzyme was purified in a single step with hydroxamic acids, and its molecular weight was found to be 44 kDa. The optimum pH was 8.0, the optimum temperature was 15°C, and the optimum ionic strength was 0.4 M for the purified HRP enzyme. [ABSTRACT FROM AUTHOR]

Simple Summary: The spotted-wing drosophila (SWD), Drosophila suzukii, is an invasive pest of soft-skinned fruits that has rapidly spread across the globe and causes hundreds of millions of dollars in crop losses worldwide. Today, the management of SWD heavily relies on the application of synthetic pesticides, which are potentially hazardous to humans, animals, other organisms, and the environment. A natural-product-based sustainable integrated pest management approach is urgently needed to reduce conventional synthetic pesticide usages. A promising behavior-based control method is the "push–pull" strategy, which uses a repellent to drive pests away from fruits (push) and towards SWD attractant-baited mass trapping devices (pull). Methyl benzoate, a naturally occurring chemical found in many plants and FDA-approved food additives, was found to be repellent to SWD in laboratory tests. In this study, we tested whether this compound could also be used to protect blueberries from SWD injury in the field. Our results demonstrated that methyl benzoate as a spatial repellent/oviposition deterrent can be deployed in blueberry fields to reduce the damage caused by SWD, although this repellent is not sufficient to act as a control strategy alone and will need to be integrated with other strategies to provide adequate protection to growers. We evaluated a novel push–pull control strategy for protecting highbush blueberry, Vaccinium corymbosum, against spotted-wing drosophila (SWD), Drosophila suzukii. Methyl benzoate (MB) was used as the pushing agent and a previously tested SWD attractive blend of lure-scents was used as the pulling agent. MB dispensers (push) were hung in the canopy and lure-scent dispensers (pull) were hung in yellow jacket traps filled with soapy water around the blueberry bushes. Blueberries were sampled weekly, and any infestation was inspected by examining the breathing tubes of SWD eggs which protrude through the skin of infested fruit. The frequency of infestation, i.e., the proportion of berries infested with at least one egg, and the extent of infestation, i.e., the mean number of eggs in infested berries, were significantly reduced in treatments receiving MB dispensers as a pushing agent when infestation rates were very high. However, the mass trapping devices as a pulling agent did not provide comparable protection on their own and did not produce additive protection when used in combination with the MB dispensers in push–pull trials. We conclude that MB has the potential to be implemented as a spatial repellent/oviposition deterrent to reduce SWD damage in blueberry under field conditions and does not require the SWD attractant as a pulling agent to achieve crop protection. [ABSTRACT FROM AUTHOR]

The synthesis of benzaldehyde, a compound widely utilized in food, medicine, and cosmetics, was achieved through a one-step catalytic hydrogenation using the cost-effective raw material, methyl benzoate. This process aligns with the principles of atom economy and green production. Despite the development of numerous high-performance catalysts by scholars, the challenge remains in achieving lower reaction temperatures, ideally below 400 °C. In this study, a series of MnOx/γ-Al2O3 catalysts were meticulously prepared using the precipitation-impregnation method. These catalysts featured supports calcined at various temperatures and distinct manganese active components. Characterization techniques such as X-ray diffraction (XRD), N2 physical adsorption, Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), H2 temperature programmed reduction (H2-TPR), and NH3 temperature-programmed desorption (NH3-TPD) were employed to analyze the structure and surface properties of the catalysts. Notably, the optimized reaction temperature was found to be 360 °C. The catalyst exhibited the most favorable performance when the calcination temperature of the support was 500 °C and the Mn/Al molar ratio reached 0.18. Under these conditions, the catalyst demonstrated the most suitable oxygen vacancy concentration, yielding impressive results: a conversion rate of 87.90% and a benzaldehyde selectivity of 86.1%. These achievements were attained at 360 °C, atmospheric pressure, a hydrogen to methyl benzoate molar ratio of 40:1, and a Gas Hourly Space Velocity (GHSV) of 800 h−1. This research underscores the potential for optimizing catalysts to enhance the efficiency and sustainability of benzaldehyde synthesis. [ABSTRACT FROM AUTHOR]

Rhododendron fortunei belongs to a scented Rhododendron species native to China, which produces fragrant flowers of great ornamental and environmental values for landscaping or indoor beautification. However, the scents in Rhododendron fortunei have not yet been investigated, let alone the mechanism of the formation of these fragrance in the flowers. In this study, we measured the scents in terms of its volatile components and contents (VOC) in Rhododendron fortunei at four different flowering stages and in different tissues of the plant by headspace solid-phase micro-extraction combined (HS-SPME) with gas chromatography-mass spectrometry (GC-MS). Then the characteristic aromatic values, which reflects the degree of scent perception by human, of each VOC in the plant was calculated according to its respective aromatic thresholds. Results showed that three main VOCs measured from highest to lowest are methyl benzoates, terpenes and fatty acid derivatives. Their content increased after the flower bud opening and reached the highest at half to full blossom. In a flower most VOC contents were measured in petals and only trace amount in other tissues such as stamen, pistil. A small amount of VOCs was determined in leaves as well.All aromatic values were almost corresponded to the contents of three main VOCs, indicating that the flower fragrance arises truly from these VOC components. S-adenosyl-L-methionine: benzoic acid carboxyl methyl transferase (BAMT) catalyzes the final step to form methyl benzoates. To understand the mechanism of the formation of this main type fragrance and its regulation, we firstly isolate a gene of RfBAMT from petal of Rhododendron fortunei by using homologous cloning and RACE technology. The full length of its cDNA was 1383 bp，with an open reading frame of 1104 bp, encoding a total of 368 amino acids. The phylogenetic tree analysis showed that RfBAMT was the closest to the BSMT of Camellia japonica, belonging to methyltransferases family. Then we measured the expression level of RfBAMT again at four flower developmental stages and in different flower tissues and leaves. The results showed that the expression level of this gene was highly positively correlated with the emitted content of methyl benzoates in the flowering, implying that RfBAMT plays a pivotal role in the formation and regulation of methyl benzoates in Rhododendron fortune.This researchshowed that the RfBAMT was cloned and identified in our study and its expression level was highly positively correlated with the emitted content of methyl benzoates in the flowers and leaves, which indicated this gene may play an important role on regulation of methyl benzoate synthesis in Rhododendron fortunei. [ABSTRACT FROM AUTHOR]

Ethyl salicylate (EtSA) and ethyl benzoate (EtBZ) as alternative extraction solvents have been evaluated for vortex-assisted surfactant-enhanced emulsification microextraction (VASEME) of target fungicides (e.g. carbendazim, thiabendazole, and fuberidazole) before the high-performance liquid chromatographic analysis. Under optimum conditions, the preconcentration factors about 16–28 (18–33) and limits of detection in the range of 0.01–0.1 µg/L were achieved for both extraction solvents. Good recoveries in the range of 76.2–118.4% (85.7–114.6%) with the acceptable relative standard deviation lower than 10.4 were obtained at the concentration evaluation of 20 µg/L and 50 µg/L each fungicide in different water sample matrices. As a result, the proposed extraction solvents can be used as an alternative to other related solvents like methyl salicylate (MeSA) and methyl benzoate (MeBZ) for the preconcentration of target fungicides. [ABSTRACT FROM AUTHOR]

Lily is one of the most important cut flowers in the world, with a rich floral fragrance. To further explore the fragrance emission mechanisms of lily cultivars, headspace solid-phase microextraction–gas chromatography–mass spectrometry (HS-SPME-GC-MS) and organic solvent extraction–gas chromatography–mass spectrometry (OSE-GC-MS) were used to unveil the volatile organic compounds (VOCs) and endogenous extracts of seven lily cultivars. Furthermore, real-time quantitative PCR (qRT-PCR) was used to determine the expression levels of two key genes (TPS and BSMT) related to the biosynthesis of monoterpenoids and methyl benzoate. The results show that forty-five VOCs were detected in the petals of seven lily cultivars, and the main compounds were monoterpenoids and phenylpropanoids/benzenoids. Dichloromethane was the best solvent for extracting the endogenous extracts of Lilium 'Viviana' petals and eighteen endogenous extracts were detected using dichloromethane to extract the petals of seven lily cultivars. Each compound's emission ratio (natural logarithm of the ratio of VOC content to endogenous extract content) was calculated, and linear regression analyses between emission ratios and boiling points were conducted. Significant linear negative correlations existed between the emission ratios and boiling points of compounds, and the regression equations' coefficients of determination (R2) were all greater than 0.7. TPS was expressed highly in 'Viviana', 'Pink News', and 'Palazzo', and BSMT was expressed highly in 'Pink News' and 'Palazzo'. Correlation analyses between the gene expression levels and the monoterpenoids and methyl benzoate contents found that the TPS expression levels have strong positive correlations with monoterpenoids content, while no correlations were found between the expression levels of BSMT and the contents of methyl benzoate. This study lays the foundation for research on the release patterns of VOCs in the flowers of Lilium, and the breeding of lilies for their floral fragrance. [ABSTRACT FROM AUTHOR]

Methyl 2-(2-oxo-2H-chromen-4-ylamino)benzoate, C17H13NO4 (1), was prepared by condensation between 4-hydroxycoumarin and methyl 2-aminobenzoate. It crystallizes in the orthorhombic space group Pca21 at 300 K. The molecule of compound 1 consists of the 2H-chromen-2-one part connected by an amine moiety (-NH-) to the methyl benzoate ring. The supramolecular array is formed by hydrogen bonds between the aromatic ring and the O atoms of the lactone and ester portions. The structural details match the spectroscopic data acquired from NMR and IR spectroscopy. [ABSTRACT FROM AUTHOR]

Abstract Methyl benzoate (MB) is a common component of floral scents released by many plants. Recent research showed that MB was an alternative insecticide to control insect pests. However, the molecular mechanisms of insect pests in responses to MB are largely unknown, which limits the future applications of this promising insecticidal candidate. In this study, the total transcriptomic analysis for red flour beetle larvae after MB fumigation was performed. Of the 430 identified differentially expressed genes, 197 were upregulated and 233 were downregulated. GO and KEGG pathway enrichment were used to interpret gene classification/function and metabolic/signaling pathways, respectively. And we performed RT-qPCR to validate expressional profiles of identified DEGs. Genes that are involved in energy metabolism, xenobiotic metabolism, and digestive enzymes were shown to be differentially expressed, suggesting that MB have an impact on these physiological processes. This research will enrich our knowledge about the mechanisms of MB-fumigation response genes for stored-product pests. A better understanding of molecular response to MB will facilitate future applications to control stored-product pests. [ABSTRACT FROM AUTHOR]

In this paper the density functional theory (DFT) method was employed to investigate the cross‐coupling of methanol with benzyl alcohol to afford methyl benzoate, catalysed by Mn‐PNN pincer complex. The whole reaction process mainly includes three stages: the dehydrogenation of benzyl alcohol to benzaldehyde, the coupling of benzaldehyde with methanol to hemiacetal and the dehydrogenation of hemiacetal to methyl benzoate. The calculated results indicated that two dehydrogenation processes are influenced by two competitive mechanisms of inner and outer spheres. Dehydrogenation of benzyl alcohol to benzaldehyde is the rate‐determining step of the whole reaction, with the energy barrier of 22.1 kcal/mol. In addition, the regeneration of catalyst is also extremely important. Compared with direct dehydrogenation, the dehydrogenation mode assisted by formic acid is more advantageous. This work might provide theoretical insights and shed light on the design of cheap transition‐metal catalysts for the dehydrogenation reaction. [ABSTRACT FROM AUTHOR]

The catalytic activity and cyclic catalysis of different methyl benzoates were studied by using a series of Lewis solid acid catalysts. The iron-supported zirconium/titanium solid acid catalysts were characterized using FTIR, SEM, XRD, and BET. The details of catalytic activity and cyclic catalysis verified that the catalyst catalyzed the reactions of 31 benzoic acids with different substituents and methanol. In addition, the mechanism was revealed according to the microstructure, acid strength, and specific surface area of the catalysts, and the yields of methyl benzoates by the GC-MS. Zr ions had significant effects on the catalytic activity of the catalyst. A certain proportion of Fe and Ti ions additionally enhanced the catalytic activity of the catalyst, with the catalyst-specific composition of Fe:Zr:Ti = 2:1:1 showing optimal catalytic activity. A variety of substituents in the benzene ring, such as the electron-withdrawing group, the electron-donating group, large steric hindrance, and the position of the group on the benzene ring, had regular effects on the catalytic activity of the methyl benzoates. An increase in the catalyst activity occurred owing to the increases in the catalyst surface and the number of acid sites after the Fe ion was added. The catalytic activity remained unchanged after the facile recycling method was performed. [ABSTRACT FROM AUTHOR]

Methyl benzoate (MB) compounds are prepared by reacting various benzoic acids with methanol using an acidic catalyst. In this study, the solid acids of zirconium metal solids fixed with various substances were studied. We determined that zirconium metal catalysts with fixed Ti had the best activity. The catalytic synthesis of a series of MB compounds using titanium zirconium solid acids was studied. The direct condensation of benzoic acid and methanol using a metallic Lewis acid without other auxiliary Bronsted acids is reported for the first time. [ABSTRACT FROM AUTHOR]

A new series of 3-(5-aryl-1-phenyl-1H-pyrazol-3-yl)-5-aryl-1,2,4-oxadiazole (9a–x) have been synthesized by a reaction of 5-aryl-N′-hydroxy-1-phenyl-1H-pyrazole-3-carboximidamide (7a–d) with substituted methyl benzoate (8a–f). The newly synthesized 3-(5-aryl-1-phenyl-1H-pyrazol-3-yl)-5-aryl-1,2,4-oxadiazole (9a–x) derivatives were characterized by spectroscopic techniques and screened for in vitro antibacterial activity against Gram-positive bacterial strains Bacillus subtilis (NCIM 2063), Staphylococcus albus (NCIM 2178). Gram-negative bacterial strains Escherichia coli (NCIM 2574), it was noticed that compounds 9h, 9i, and 9j in which R = 4-Cl and R1 = 2-Cl/4-Cl or 4-CH3 showed good activity against B. subtilis with MIC 31.25 μg/mL against standard S. albus having MIC 7.81 μg/mL. Proteus mirabilis (NCIM 2388) and in vitro antifungal activity against Aspergillus niger (ATCC 504) Candida albicans (NCIM 3100). 3-(5-Aryl-1-phenyl-1H-pyrazol-3-yl)-5-aryl-1,2,4-oxadiazole derivatives like compound 9a (R = H, R1 = 2-Cl), 9b (R = H, R1 = 2-Cl), 9d (R = H, R1 = 4-Cl), and 9k (R = 4-Cl, R1 = 4-OCH3) showed good activity against A. niger with MIC 31.25 µg/mL, which are comparable to standard drug ravuconazole having MIC 31.5 µg/mL. Compounds 9h (R = 4-Cl, R1 = 2-Cl) and 9j (R = 4-Cl, R1 = 4-CH3) showed activity against A. niger with MIC 7.81 µg/mL which is comparable to standard drug Fluconazole having MIC 7.81 µg/mL and fourfold more activity with respect to drug Ravuconazole. The antibacterial activity of 3-(5-aryl-1-phenyl-1H-pyrazol-3-yl)-5-aryl-1,2,4-oxadiazole (9a–x) derivatives led to the conclusion that these scaffolds could aid in the creation of lead drugs to treat microbial infection. [ABSTRACT FROM AUTHOR]

The main bottleneck in inkjet printing (IJP) is a stable and jettable ink formulation. This paper discusses the ink formulation for the small molecule phosphorescent dopant/host system. The study involves the estimation of Hansen solubility parameters (HSP) to formulate inkjet‐printed ink of an iridium complex‐based phosphorescent material, bis(4‐phenylthieno[3,2‐c]pyridinato‐N,C2') (acetylacetonate) iridium(III) (PO‐01) as dopant and 4, 40‐bis (carbazol‐9‐yl) biphenyl as the host of the emissive layer. Based on dopant and host HSP analyses, toluene and methyl benzoate are chosen as ink solvents. Our ink is stable for a month and can be replicated with great accuracy. The interaction of individual drops is examined in detail since resolution or film quality is highly influenced by the drop formation and spread on a substrate. Finally, an inkjet‐printed emissive layer is demonstrated on both glass and flexible substrates. The fabricated devices exhibit the maximum current efficiency and luminance of 6.4 cd A−1 and 5781 cd m−2. A technique is also shown to print large‐area organic light‐emitting diode (OLED) devices having different patterns without patterning or pixelization of the active area of the electrodes. Up to 80 × 80 mm2 large‐area OLED tiles are made using IJP of the emissive layer. [ABSTRACT FROM AUTHOR]

It is hypothesized that in heterostylous plant species, standardization of signals of floral attraction between different morphs is advantageous, encouraging flower visitors to switch between morphs. It remains unclear whether signals of floral attraction (floral odor and properties of nectar) are similar between morphs in distylous species pollinated by hawkmoths, and how these relate to hawkmoth behavior. We observed the behavior of visitors to distylous Luculia pinceana (Rubiaceae), collected and analyzed floral odor, and examined properties of nectar (volume, sugar concentration, and composition) of long‐styled and short‐styled morphs during the day and night. Pollinator responses to the floral scent were tested with a Y‐tube olfactometer. We conducted diurnal and nocturnal pollination treatments and six other pollination treatments to test the importance of nocturnal pollinators and to examine the self‐incompatibility system. A species of hawkmoth, Cechenena lineosa, was the effective pollinator. The floral odor was rich in methyl benzoate, and sucrose was dominant in the nectar. There were no significant differences between the two morphs in the methyl benzoate content or the properties of nectar. Flowers released more methyl benzoate and secreted larger volumes of nectar with lower sugar concentration at night than during the day. The hawkmoth had a significant preference for methyl benzoate. Luculia pinceana was partially self‐incompatible and relied on nocturnal pollinators for reproductive success. This study verifies that floral attraction signals are consistent between different morphs in this distylous species, promoting compatible pollination, and the features and the diel pattern of these signals between day and night are adapted to hawkmoth behavior. [ABSTRACT FROM AUTHOR]

Quadruple-bond dimolybdenum complexes provide invaluable insight into the two-electron bond, with structural chemistry providing a foundation for examination of bond properties. The synthesis and solid-state structure of the quadruple-bonded dimolybdenum(II) complex tetra­kis­(μ-4-methyl­benzoato-κ²O:O′)bis[(tetra­hydro­furan-κO)molybdenum(II)] tetra­hydro­furan disolvate, [Mo2(C8H7O2)4(C4H8O)2]·2C4H8O, are presented. This complex crystallizes in a triclinic cell with low-symmetry space group P[\overline{1}]. The dimolybdenum paddlewheel structure comprises four methyl­benzoate ligands and two axial THF ligands. The dimolybdenum bond distance of 2.1012 (4) Å is exemplary of this class of compounds. [ABSTRACT FROM AUTHOR]

The compounds of the homologous series of n-alkyl benzoates (PhCOO-n-CnH2n+1) have a number of important applications. As for many low-volatile compounds, a few data on the vaporization thermodynamics of this class of compounds are available. Here we systemized and critically analyzed the available information on vapor pressures and vaporization enthalpies of short linear alkyl benzoates from methyl to pentyl and complemented these data by additional experimental investigation of long-chained compounds: the heat capacities and vapor pressures of pentadecyl, hexadecyl and heptadecyl benzoates were measured for the first time between 340 and 490 K using DSC and TG-FSC. Based on the experimental data and empirical approaches, we completely described the vaporization thermodynamics of a series of alkyl benzoates from methyl to eicosyl and established the correlation of some properties with the chain length. A way to predict the vaporization enthalpies and vapor pressures inside the homologous series in a wide temperature range was proposed and tested. [ABSTRACT FROM AUTHOR]

Soil microbes are an abundant source of enzymes with unique properties that may be useful for industrial applications. As most wild-type strains show low chlorogenic acid esterase expression and activity, and most microbes cannot be cultured in the laboratory, a metagenomic approach provides methods of identifying new enzymes. In this study, a gene encoding a chlorogenic acid esterase, named Tan410, was isolated from a soil metagenomic library and overexpressed in Escherichia coli BL21 (DE3). The recombinant enzyme, with a predicted molecular weight of 54.88 kDa, was purified to homogeneity. The Km and Vmax values for Tan410 were 1.26 mM and 0.33 mM min–1, respectively, with chlorogenic acid as the substrate. Its optimum temperature and pH for reaction were 30 °C and 7.5, respectively. The enzyme exhibited moderate thermostability and broad pH stability (3.0–10.0). Tan410 was also able to hydrolyse ethyl ferulate, methyl caffeate, propyl gallate, ethyl gallate, methyl vanillate, methyl benzoate, ethyl benzoate, methyl 2,5-dihydroxybenzoate, and methyl 3,5-dihydroxybenzoate, and it released caffeic and ferulic acids from agricultural byproducts (destarched wheat bran and coffee pulp). Tan140 has potential for industrial application in biomass valorization. [ABSTRACT FROM AUTHOR]

Two new biphenylpropanoids (1 and 2) were isolated from the rhizomes of Acorus tatarinowii Schott. The structures of compounds 1 and 2 were determined by means of extensive spectroscopic methods. Their structures were identified as (R)-3-[1-hydroxy-3-(3,4-dimethoxyphenyl)propan-2-yl]-4,5-dimethoxy methyl benzoate (1) and (R)-3-[1-hydroxy-3-(3,4-dimethoxyphenyl)propan-2-yl]-4,5-dimethoxy ethyl benzoate (2). In addition, the xanthine oxidase (XOD) inhibitory activity of the isolated compounds was reported. Compounds 1 and 2 exhibited weak XOD inhibitory activity in the test. [ABSTRACT FROM AUTHOR]

The eastern Apis cerana (Ac) and the western Apis mellifera (Am) are two closely related and most economically valuable honeybee species managed extensively worldwide. However, how worker bees of Ac and Am are adapted to their colony organization remains to be uncovered. Here, we found that the expression level of gene encoding antennae-specific proteins 1 (ASP1, a key regulator in recognizing queen mandibular pheromone) was positively correlated with the colony sizes in both bee species, and the expression level in Am was higher than that in Ac , suggesting that ASP1 may play an important role in maintaining colony homeostasis. Using competitive binding assay, molecular docking, and site-directed mutagenesis, we then confirmed the good binding affinities of both Ac-ASP1 and Am-ASP1 to methyl p-hydroxy benzoate (HOB), and Val115 was the key amino acid. However, the affinity of Am-ASP1 was stronger than that of Ac-ASP1. EAG analysis further demonstrated that antennae of Am worker bees had faster depolarization and repolarization in response to HOB stimulation. Taken together, these findings indicate that the differences in expression levels and binding dynamics allow ASP1 recognizing HOB to potentially serve as a specific regulator of colony organization in Ac and Am. [ABSTRACT FROM AUTHOR]

Cholinesterase (ChE) inhibitors are an important group of drugs used in Alzheimer's, glaucoma, and myasthenia gravis. In recent years, cholinesterase inhibition potentials of compounds have been investigated in new drug discovery studies. In this study (5-formylfuran-2-yl) methyl 4-nitro benzoate (compound 1) and newly designed (5-formylfuran-2-yl) methyl 3,4-dimethoxybenzoate (compound 2) were synthesized. The chemical structures of the synthesized compounds were characterized by spectral data (HRMS, ¹H NMR, and 13C NMR). The ChE inhibitory activity of the compounds was evaluated using in vitro colorimetric Ellman method. Compound 1 and compound 2 exhibited inhibitory activity against AChE at IC50 values of 3.25 µM and 8.45 µM, respectively. Compound 1 and Compound 2 showed inhibitory activity against BuChE at IC50 values of 8.45 µM and 14.44 µM, respectively. In Docking simulations with 1EVE and 1P0I, the binding free energy scores of compound 1 were higher than the binding free energy scores of compound 2. In this respect, in silico molecular docking studies overlapped with in vitro enzyme inhibition studies. These derivatives can be used to develop new drugs such as cholinesterase inhibitors. [ABSTRACT FROM AUTHOR]

Phenolic acids represent a large collection of phytochemical molecules present in the plant kingdom; they have an important role as epigenetic regulators, particularly as inhibitors of DNA methylation. In the present study, 14 methyl benzoate and cinnamate analogs were synthesized (11–24). Their cytotoxic activity on hepatocellular carcinoma cells (Hep3B) and immortalized human hepatocyte cells was then evaluated. In addition, its effect on the inhibition of global DNA methylation in Hep3B was also determined. Our results showed that the cinnamic derivatives 11–14 and 20–22 were more potent than the free caffeic acid (IC50 109.7–364.2 µM), being methyl 3,4‐dihydroxycinammate (12) the most active with an IC50 = 109.7 ± 0.8 µM. Furthermore, 11–14, 20–23 compounds decreased overall DNA methylation levels by 63% to 97%. The analogs methyl 4‐hydroxycinnamate (11), methyl 3,4,5‐trimethoxycinnamate (14), methyl 4‐methoxycinnamate (21), and methyl 3,4‐dimethoxycinnamate (22) showed relevant activities of both cytotoxicity and global DNA methylation inhibition. The molecular docking of 21 and 14 suggested that they partly bind to the SAH‐binding pocket of DNA methyltransferase 1. These results emphasize the importance of natural products and their analogs as potential sources of DNA methylation modulating agents. [ABSTRACT FROM AUTHOR]

Nanoemulsion provides an effective way for the efficient, safe, and environmentally friendly use of pesticides. In this study, the influence of different type emulsifiers on the formation and stability of nanoemulsion were tested and an optimal pyraclostrobin nanoemulsion with long-term stability was obtained. Pyraclostrobin (2.5 %), #602 (phenylethyl phenol polyoxyethylene ether, 6 %), and #600 P (tristyryl- phenol polyoxyethylene ether phosphate, 2 %) were dissolved in methyl benzoate (2.5 %) and co-emulsifier ethanol (20 %) with deionized water replenished to 100 %. Compared with microemulsion (ME), the nanoemulsion using a lower dosage of emulsifier kept the system stable for a long time, reducing pollution of the environment. Compared with the commercial ME and suspension concentrate (SC), the nanoemulsion had a lower contact angle and surface tension, and higher maximum retention. In addition, adding 0.01 % AEO-3 (dodecyl alcohol polyol ethylene ether) to the dilution of nanoemulsion can significantly improve the target deposition of the nanoemulsion and improve the utilization rate of the pesticide. Besides, the use of methyl benzoate, an environmentally friendly solvent, resulted in the nanoemulsion with high bactericidal activity and low acute toxicity to zebrafish, thus reducing the environmental pollution of such chemicals. [Display omitted] • Pyraclostrobin nanoemulsion with environmentally friendly methyl benzoate as solvent was developed. • Pyraclostrobin nanoemulsion prepared by screening different types of emulsifiers meets the product quality requirements. • The developed pyraclostrobin nanoemulsion can improve the target deposition on target leaves. • Pyraclostrobin nanoemulsion exhibited high bactericidal activity and low acute toxicity. [ABSTRACT FROM AUTHOR]

Contaminated food contact surfaces play a vital role in spreading Staphylococcus aureus to consumers, resulting in several staphylococcal foodborne outbreaks. This highlights the significance of proper and effective sanitization of food contact surfaces. Although chemical sanitizers are widely used for this purpose, the growing tendency of consumers toward avoiding their uses due to their health hazards in addition to their economic drawbacks shifted our attention to investigating alternative natural compounds. This study aimed to evaluate the efficacy of natural antimicrobial agents, including caprylic acid (CA), lauric arginate ester (LAE), benzyl alcohol (BA), benzyl benzoate (BB), and methyl benzoate (MB), at practical concentrations against S. aureus biofilms on stainless steel surfaces. In general, the antimicrobial efficacies of the investigated sanitizers were enhanced either by increasing their concentrations or by extending the exposure time from 1 to 5 min. The 5-min treatment of 400 ppm CA, 1.0% BA, 1.0% BB, and 1.0% MB reduced the S. aureus biofilm with ∼3.9, 3.4, 2.3, and 2.3 log CFU/coupon, respectively. However, organic matter conditioning of the stainless steel surfaces with diluted whole milk counteracted the antimicrobial efficacies of all the investigated sanitizers. The 5-min treatment of 200 ppm LAE caused ∼2.6 log CFU/coupon reduction of S. aureus biofilm on soiled surfaces, compared to ∼4.4 log CFU/coupon reduction on clean surfaces. The obtained data provide practical information and guidance for effective sanitization of food contact surfaces in the food sector. • Organic matter soiling didn't affect S. aureus biofilm formation on surfaces. • The efficacy of all investigated sanitizers was concentration-dependent. • Increasing exposure time to investigated sanitizers enhanced their efficacy. • The efficacy of investigated sanitizers was reduced by organic matter presence. • LAE (200 ppm, 5-min) reduced 4.4 log S. aureus biofilm on clean surfaces. [ABSTRACT FROM AUTHOR]

The aim of this study is to evaluate the phytochemical profile, oral acute toxicity, and the effect of ylang-ylang (Cananga odorata Hook. F. & Thomson) essential oil (YEO) on acute inflammation. YEO was analyzed by gas chromatography/mass spectrometry. For in vitro tests, YEO was assessed using cytotoxicity, neutrophil chemotaxis induced by N-formyl methionyl leucyl phenylalanine (fMLP), and phagocytic activity tests. YEO was orally administered in zymosan-induced peritonitis, carrageenan-induced leukocyte rolling, and adhesion events in the in situ microcirculation model and in carrageenan-induced paw edema models. YEO (2000 mg/kg) was also tested using an acute toxicity test in Swiss mice. YEO showed a predominance of benzyl acetate, linalool, benzyl benzoate, and methyl benzoate. YEO did not present in vitro cytotoxicity. YEO reduced the in vitro neutrophil chemotaxis induced by fMLP and reduced the phagocytic activity. The oral treatment with YEO reduced the leukocyte recruitment and nitric oxide production in the zymosan-induced peritonitis model, reduced rolling and adherent leukocyte number induced by carrageenan in the in situ microcirculation model, and reduced carrageenan-induced edema and mechanical hyperalgesia. YEO did not present signs of toxicity in the acute toxicity test. In conclusion, YEO affected the leukocyte activation, and presented antiedematogenic, anti-hyperalgesic, and anti-inflammatory properties. [ABSTRACT FROM AUTHOR]

Simple Summary: The stick tea thrip Dendrothrips minowai is a key pest in tea plantations in China. In recent years, plant-derived semiochemicals have attracted considerable attention as promising attractants for the management of thrips, due to their safety and low cost. In this study, compounds that have been reported to attract other thrips or emitted from tea plants were evaluated for their electroantennogram (EAG), behavioral tests and field trapping efficacy for D. minowai. The EAG relative response value of D. minowai evoked by p-anisaldehyde, 3-methyl butanal, (E)-β-ocimene, farnesene, nonanal, eugenol, (+)-α-pinene, limonene, (−)-α-pinene, and γ-terpinene was significantly higher than the other compounds. Meanwhile, p-anisaldehyde, eugenol, farnesene, methyl benzoate, 3-methyl butanal, (E)-β-ocimene, (−)-α-pinene, (+)-α-pinene, and γ-terpinene led to attraction or repellency responses of female D. minowai. In addition, trap capture numbers of female D. minowai on sticky traps baited with p-anisaldehyde, eugenol, farnesene, and 3-methyl butanal were significantly higher than the control in tea plantations. Overall, our results highlight the potential application of plant volatiles in the development of effective, eco-friendly lure formulations for use in the monitoring and management of thrips. The stick tea thrip (Dendrothrips minowai Priesner) is the main pest thrip in tea (Camellia sinensis) plantations in China, and seriously affects the quality and yield of tea. Plant-derived semiochemicals provide an alternative to pheromones as lures and these compounds possess powerful attractiveness. In this study, we selected 20 non-pheromone semiochemicals, including compounds that have been reported to attract other thrips and some volatiles emitted from tea plants as the potential attractant components for D. minowai. In electroantennogram (EAG) assays, 10 synthetic compounds (p-anisaldehyde, 3-methyl butanal, (E)-β-ocimene, farnesene, nonanal, eugenol, (+)-α-pinene, limonene, (−)-α-pinene, and γ-terpinene) elicited significant antennal responses in female D. minowai. In addition, a two-choice H-tube olfactometer bioassay showed that D. minowai displayed significant positive responses to eight compound dilutions (p-anisaldehyde, eugenol, farnesene, methyl benzoate, 3-methyl butanal, (E)-β-ocimene, (−)-α-pinene, and (+)-α-pinene) when compared with the solvent control at both 1 and 2 h. Moreover, γ-terpinene exhibited a significantly deterrent effect on D. minowai. Finally, trap catches of four compounds (p-anisaldehyde, eugenol, farnesene, and 3-methyl butanal, respectively) significantly increase in tea plantations. Among these, the maximum number of D. minowai collected by blue sticky traps baited with p-anisaldehyde was 7.7 times higher than the control. In conclusion, p-anisaldehyde, eugenol, farnesene, and 3-methyl butanal could significantly attract D. minowai in the laboratory and under field conditions, suggesting considerable potential as commercial attractants to control D. minowai populations. [ABSTRACT FROM AUTHOR]

Methyl 2-hydroxy-5-[(trimethylsilyl)ethynyl]benzoate and methyl 2-hydroxy-5-ethynylbenzoate have been synthesized, and the crystallographic data on these compounds are reported. Due to their planar molecular structures, both compounds are layered. At the same time, planar molecules do not form a stack packing. In methyl 2-hydroxy-5-ethynylbenzoate, molecules in a layer are bound by hydrogen bonds (including those involving the terminal proton of the ethynyl group). The IR spectra are reported, and the fundamental absorption bands are interpreted for both compounds. The photoluminescence spectrum of methyl 2-hydroxy-5-[(trimethylsilyl)ethynyl]benzoate is also recorded: the emission maxima in the solid state and in chloroform solution are located at ~566 and 500 nm, respectively. [ABSTRACT FROM AUTHOR]

The pentose phosphate pathway (PPP), whose products are vital in biosynthetic events, is targeted in the treatment of many diseases such as cancer and malaria. The objective of this study was to identify new PPP inhibitors. The inhibition effects of methyl 4‐amino benzoates on glucose 6‐phosphate dehydrogenase (G6PD) and 6‐phosphogluconate dehydrogenase (6PGD) were analyzed through in vitro experiments and molecular docking studies were used to estimate inhibition mechanisms. IC50 values of compounds were found between 100.8 and 430.8 μM for G6PD and 206 and 693.2 μM for 6PGD. Molecular docking analysis showed that compound 1 was found the most effective inhibitor against hG6PD and compound 4 had the highest inhibitory potency against h6PGD with the estimated binding energy of −6.71 and −7.61 kcal/mol, respectively. In conclusion, it was determined that in vitro and in silico outcomes of the study were highly correlated with each other. The structure of these benzoates may aid in the development of drugs that target the PPP. [ABSTRACT FROM AUTHOR]

Poly-L-lactic acid (PLLA) aerogel-based scaffolds were obtained from physical PLLA gels containing cyclopentanone (CPO) or methyl benzoate (BzOMe) molecules. An innovative single step method of solvent extraction, using supercritical CO2, was used to achieve cylindrical monolithic aerogels. The pore distribution and size, analyzed by SEM microscopy, were found to be related to the crystalline forms present in the physical nodes that hold the gels together, the stable α'-form and the metastable co-crystalline ε-form, detected in the PLLA/BzOMe and PLLA/CPO aerogels, respectively. A higher mechanical compressive strength was found for the PLLA/CPO aerogels, which exhibit a more homogenous porosity. In vitro biocompatibility tests also indicated that monolithic PLLA/CPO aerogels exhibited greater cell viability than PLLA/BzOMe aerogels. An improved biocompatibility of PLLA/CPO monolithic aerogels was finally observed by coating the surface of the aerogels with polydopamine (PDA) obtained by the in situ polymerization of dopamine (DA). The synergistic effect of biodegradable polyester (PLLA) and the biomimetic interface (PDA) makes this new 3D porous scaffold, with porosity and mechanical properties that are tunable based on the solvent used in the preparation process, attractive for tissue engineering applications. [ABSTRACT FROM AUTHOR]

In this note we report the synthesis of a doubly acylated cis-THF-diol product synthesised in three steps by the stereoselective RuO4-catalysed oxidative cyclisation of 1,5-hexadiene, followed by benzoylation and acetylation. This substance is one of the substrates chosen to probe a new developed oxidative procedure to transform bis-acylated THF-diols into bis-acylated 1,4-diketones. This new derivative was fully characterised by spectroscopic methods. [ABSTRACT FROM AUTHOR]

The hydrogenation of esters catalyzed by a manganese complex of phosphine‐aminopyridine ligand was developed. Using this protocol, a variety of (hetero)aromatic and aliphatic carboxylates including biomass‐derived esters and lactones were hydrogenated to primary alcohols with 63–98% yields. The manganese catalyst was found to be active for the hydrogenation of methyl benzoate, providing benzyl alcohol with turnover numbers (TON) as high as 45,000. Investigation of catalyst intermediates indicated that the amido manganese complex was the active catalyst species for the reaction. [ABSTRACT FROM AUTHOR]

• Methyl benzoate; a safety assessment based on RIFM's criteria. • A safety assessment based on 7 human health endpoints plus environmental. • All endpoints were cleared using target data, read-across, and/or TTC. [ABSTRACT FROM AUTHOR]

In this study, headspace solid‐phase microextraction coupled with gas chromatography‐mass spectrometry (HS‐SPME‐GC/MS) was used to identify individual volatile compounds in five jujube varieties, and E‐nose was used to identify their flavor. The results showed that a total of 45 volatile compounds were detected by GC‐MS in the five varieties, and the proportion of acids was the highest (38.29%–54.95%), followed by that of aldehydes (22.94%–47.93%) and esters (6.33%–26.61%). Moreover, different varieties had obviously different volatile components. E‐nose analysis showed that the R7 and R9 sensors were more sensitive to the aroma of jujube than other sensors. The strong response of R7 sensor was attributed to terpenes (or structurally similar substances) in jujube fruit, such as 1‐penten‐3‐one, 2‐octenal, (E)‐2‐heptanaldehyde, and (E)‐2‐hexenal and that of R9 sensor was attributed to the cyclic volatile components such as benzaldehyde, benzoic acid, and methyl benzoate. The multivariate data analysis (PCA, OPLS‐DA, and HCA) of the results of GC/MS and E‐nose showed that the five varieties could be divided into three groups: (1) Ziziphus jujuba Mill. cv. Huizao (HZ) and Z. jujuba cv. Junzao (JZ). Acids were the main volatile components for this group (accounting for 47.44% and 54.95%, respectively); (2) Z. jujuba cv. Hamidazao (HMDZ). This group had the most abundant volatile components (41), and the concentrations were also the highest (1285.43 µg/kg); (3) Winter jujube 1 (Z. jujuba cv. Dongzao, WJ1) and Winter jujube 2 (Z. jujuba cv. Dongzao, WJ2). The proportion of acids (38.38% and 38.29%) and aldehydes (40.35% and 38.19%) were similar in the two varieties. Therefore, the combination of headspace solid‐phase microextraction coupled with gas chromatography‐mass spectrometry and E‐nose could quickly and accurately identify the volatile components in jujube varieties from macro‐ and microperspectives. This study can provide guidance for the evaluation and distinguishing of jujube varieties and jujube cultivation and processing. [ABSTRACT FROM AUTHOR]

Theoretical computations of charge density parameters are juxtaposed to experimental spectroscopic shifts induced by hydrogen bonding for a series of 21 substituted in the aromatic ring ethyl and methyl benzoates. Strong correlations between atomic charges at the proton accepting atom and the shifts of methanol O-H frequencies are established. Hirshfeld, Charge Model 5 (CM5), and natural population analysis (NPA) atomic charges are evaluated using B97X-D/6-311++G(3df,2pd) and MP2/6-311++G(3df,2pd) computations. The results obtained reveal the power of hydrogen bond measurements in characterizing the variations of electron densities at the proton accepting center within a series of structurally related molecules. The limits of application of the approach are outlined. [ABSTRACT FROM AUTHOR]

Volatile analyses of cacti have previously been performed on the flowers, fruits, and consumed stems. During our own investigations, we and others have observed that the cut stems of certain species of the Graveolens clade of Cylindropuntia emitted odors similar to those of rancid butter or cyanoacrylate. Some species of Consolea, Opuntia, Quiabentia, and Tacinga were found to produce similar odors. Fresh samples of Cylindropuntia and these other genera were collected, and the volatile compound profiles were analyzed by solid phase micro-extraction gas chromatography mass spectrometry. Linear discriminate analysis found the compounds to be characteristic of the odiferous cacti as the aldehydes hexanal, 2-hexenal, and nonanal; the alcohol phenethyl alcohol; the terpene β-phellandrene; the ketone β-ionone; and the diol 5-pentyl-1,3-benzenediol. Compounds characteristic of the non-odiferous cacti are the ketones 6-methyl-2-heptanone, 2-octanone, and 1,3-dihydro-5-methyl-2H-benzimidazol-2-one; the alkanes undecane, tridecane, pentadecane, and heptadecane; the aromatics p-cymene and 1,2,3,5-tetramethyl benzene; the esters octyl formate, methyl benzoate, and methyl salicylate; the aldehyde 2-octenal; the alcohol cyclooctyl alcohol; the imine methoxy-phenyl-oxime; the terpene 1-methyl-2-(2-propenyl)-benzene; and nine unknown compounds. Putative hybrid cacti were found to have a unique volatile profile in comparison to the parents. Additionally, differing infraspecific chromosome races, diploids (n = 11) and tetraploids (n = 22), were found to have differing volatile profiles with some compounds increasing with an increase in chromosome number while other compounds decreased with an increase in chromosome number. [ABSTRACT FROM AUTHOR]

Bulbophyllum orchid is used as a folk medicine in Asia. However, the concentrations of bioactive constituents in the plant may vary in different tissues. Thus, this study determined the most cytotoxic tissue extract in Bulbophyllum blepharistes Rchb.f. and identified its cytotoxic bioactive compounds. The ethanol extract from rhizomes of B. blepharistes exhibits more cytotoxicity than extracts from the leaf and pseudobulb. Ten compounds isolated from the rhizome are phenanthrenes (1, 2), bibenzyls (3, 4, 5), phenylpropanoids (6), methyl benzoate (7), along with a mixture of three alkyl acrylates (8, 9, 10). Compound 2, lusianthridin (9,10-dihydro-7-methoxy-2,5-phenanthrenediol), which was reported here for the first time in Bulbophyllum , showed cytotoxicity to H69AR, HeLa, HL-60, HepG2, and MOLT-3 cells. Compound 1 and 5 (tristin) significantly inhibited the growth of MOLT-3. The rhizome of B. blepharistes appears to be a good source for the potential anticancer agents (i.e. lusianthridin). [Display omitted] • Among18 genera of Orchidaceae, the extract of Bulbophyllum showed the most cytotoxic effect. • The ethanolic extract from rhizome of Bulbophyllum orchid rich in bioactive compounds. • The cytotoxic of Bulbophyllum dihydrophenanthrene and bibenzyl effect to various cell lines. [ABSTRACT FROM AUTHOR]

Benzoic acid, methyl benzoate compounds and their derivatives are valuable compounds that have a wide range of activities and synthesis of these is important for organic chemists. In this study, the synthesis of methyl-4,5-dimethoxy-2-(2-(4-methoxyphenyl)-2-oxoethyl) benzoate, methyl ester derivative of benzoic acid, was carried out effectively as a result of a series of reactions starting from 3,4-dimethoxycinnamic acid. The structure of synthesized compound was characterized by ¹H NMR and 13C NMR spectra. [ABSTRACT FROM AUTHOR]

Lisianthus (Eustoma grandiflorum), a leading plant in the cut flower industry, is scentless. Here we show that lisianthus flowers have potential to produce several fragrant benzenoid‐phenylpropanoids when substrate availability is not limited. To enable hyperaccumulation of substrates for the production of volatile benzenoid‐phenylpropanoids, lisianthus commercial hybrid "Excalibur Pink" was transformed via floral dipping with a feedback‐insensitive Escherichia coli DAHP synthase (AroG*) and Clarkia breweri benzyl alcohol acetyltransferase (BEAT), under constitutive promoters. The T1 progeny of "Excalibur Pink" plants segregated into four visual phenotypes, with pink or white colored petals and multiple or single petal layers. Interestingly, transformation with AroG* and BEAT caused no significant effect in the pigment composition among phenotypes, but did increase the levels of down‐stream fragrant volatile benzenoids. All the transgenic lines exclusively accumulated methyl benzoate, a fragrant benzenoid, either in their petals or leaves. Furthermore, feeding with benzyl alcohol resulted in the accumulation of two novel benzenoids, benzyl acetate (the product of BEAT) and benzoate, as well as a dramatic increase in the concentrations of additional benzenoid‐phenylpropanoid volatiles. Presumably, the degree of benzaldehyde overproduction after benzyl alcohol feeding in both leaves and flowers revealed their reverse conversion in lisianthus plants. These findings demonstrate the concealed capability of lisianthus plants to produce a wide array of fragrant benzenoid‐phenylpropanoids, given high substrate concentrations, which could in turn open opportunities for future scent engineering. [ABSTRACT FROM AUTHOR]

A reliable method for molecular structure determination, excluding single-crystal X-ray diffraction (SCXRD), has been applied to six methyl glycoside tetrabenzoates. The proposed method is based on a global conformational search using molecular mechanics and subsequent DFT calculations guided by a solid-state NMR experiment. The accuracy of the applied method has been verified on three methyl glycoside benzoates for which the SCXRD analysis has been completed. It appeared that the calculated conformations of unprivileged energy could be found in the solid state. Bulky substituents (benzoates) exerted less energetically favored interactions in crystals in contrast to isolated molecules. Therefore, solid-state NMR was revealed to be an indispensable approach for choosing credible conformations from the calculated conformations. [ABSTRACT FROM AUTHOR]

Mulberry is rich in anthocyanins. The main component is cyanidin-3-O-glucoside. Anthocyanins are hydrophilic and water-soluble polyphenolic plant pigments and metabolites, which are one of the important antioxidants. They possess a wide range of pharmacological properties, such as anti-oxidant, anti-aging, anti-inflammatory, antimicrobial, and anti-cancer. Therefore, anthocyanins have great potential in various fields, such as the pharmaceutical and food industries. However, the relatively low stability of anthocyanin limits its bioavailability and effective applications, particularly on the degradation of anthocyanin. Taking the mature mulberry fruit as research objects, this study aims to prepare and characterize acylated mulberry anthocyanins using biological enzymes. The anthocyanin was extracted with acidified ethanol solvent and then purified by D101 macroporous resin. In order to reduce the degradation of anthocyanin while improving its stability, the mulberry anthocyanin was acylated by biological enzymatic and compared with that of non-acylated anthocyanin. Lipase, reaction solvent, and acyl donor were screened by single factor experiment to explore the anthocyanin acyl conversion rate. Taking the conversion rate as the evaluation index, the optimum conditions for acylation reaction were as follows: Candida Antarctica lipase as an acylating catalytic enzyme, pyridine as a catalytic reaction solvent, methyl benzoate as acyl donor, and the acylation effect was the best. The maximum conversion rate of mulberry anthocyanin was 13.5%. The products were analyzed by Fourier transform infrared spectroscopy (FTIR), Ultraviolet-visible spectrophotometer (UV-Vis), and high-performance liquid chromatography-mass spectrometry (HPLC-MS). Acylated anthocyanin was composed of C=O absorption peak at 1 650-1 870 cm-1, -OH bending vibration absorption, and C-O-C stretching vibration absorption of phenolic molecules at 1 000-1 300cm-1. There was also a skeleton vibration peak of the benzene ring (1 420-1 600 cm-1). The non-acylated anthocyanin sample had obvious UV absorption at 280 nm, and the absorption at this wavelength was the most stable. It showed that anthocyanin contained a benzene ring and a phenolic hydroxyl group on the benzene ring. The absorption peak of acylated anthocyanins moved forward from 280 nm to 271 nm, indicating that the structure of anthocyanins had changed. The mass charge ratios of acylated anthocyanin at 287, 449 and 595 (m/z), corresponding to the peaks of procyanidin, cyanidin-3-O-glucoside， and cyanidin-3-O-rutinoside, respectively. It was identified that the acylated products were monoacyl anthocyanin at 553 (m/z) or polyacyl anthocyanin at 657 (m/z). In addition, an attempt was made to explore the effects of acylation on the stability and antioxidant properties of anthocyanin. The acylation could improve the thermal stability, photostability, and acid-base resistance of anthocyanin. At the same temperature, the preservation rate of acylated anthocyanin increased by 5.0%, and it could be better preserved at 40, 50, and 60 . Light had a great influence on the stability of ℃ anthocyanin. The preservation rate of non-acylated anthocyanin decreased linearly to 77.3% within 10 days. After 6 days of light exposure, the preservation rate of acylated anthocyanin was still as high as 96.1%. At the pH values of 2, 3 and 8, the stability of acylated anthocyanin was improved. The acylation significantly increased the antioxidant activity of anthocyanin in vitro. DPPH radical scavenging activity was enhanced. The total reducing ability was 30% higher than that of the non-acylated anthocyanin. The chelating ability of metal ions was 90% higher. The inhibition rate of acylated anthocyanin on tumor cell activity was up to 81%, while that of non-acylated anthocyanin was only 50%. Therefore, acylated anthocyanin can effectively inhibit the proliferation of tumor cells. This finding can provide a theoretical basis and technical support for the stable application and performance improvement of anthocyanin in the production fields of functional food, biomedicine, botanical pesticides, and daily cosmetics fields. [ABSTRACT FROM AUTHOR]

Highly efficient, heterogeneous catalyst PMo 11 /ZSM-5-H with enhanced activity was developed for direct oxidative esterification of aldehyde with alcohols under environmentally benign reaction conditions. [Display omitted] • Supported undecamolybdophosphate catalyst with tailored acidity and redox properties. • Direct oxidative esterification of aldehydes with environmentally benign oxidants. • > 95 % selectivity for Methyl benzoate with >15,000 TON in the presence of O 2. • Superior performance due to the synergistic effect of modulated acid-redox sites. • Heterogeneous and recyclable catalyst. Aiming to develop a novel heterogeneous catalyst for single-step oxidative cross-esterification of aldehydes to ester with enhanced activity and selectivity under benign conditions, here we report the synthesis of defect-regulated undecamolybdophosphate supported on ZSM-5. The enhancement in acidity was achieved by exchanging the available Na+ with protons using an ion-exchange protocol. The structural and morphological features of synthesized catalysts (20 % PMo 11 /ZSM-5-H) were confirmed by in-depth characterization such as acidity measurement, FT-IR, TGA, surface area measurement SEM, TEM, and PXRD. The synthesized catalysts were used for direct oxidative esterification reaction with environmentally benign oxidants (O 2 and H 2 O 2). The effect of various reaction parameters such as %loading of PMo 11 , amount of catalyst, reaction time, and reaction temperature and volume of methanol on activity and selectivity was studied. The comparative studies of supported analogous phosphomolybdates with the present catalyst showed that the enhancement in acidity and modulation in redox properties of 20 % PMo 11 /ZSM-5-H was found propitious. The novelty lies in obtaining excellent selectivity of the ester (>95 %) with an exceptionally high turnover number (>15323) with an environmentally benign oxidant O 2. The scope and limitations of the present catalytic system were also explored by employing different aldehydes and alcohols under optimized conditions. The stability and recycling studies showed that the synthesized catalyst is truly heterogeneous and can be recycled at a minimum of six cycles. From the comparative data of the reported catalysts as well as control experiments, it was concluded that the synergistic effects of enhanced acidities and tailored redox sites played vital roles in the superior performance of the present catalytic system. Based on the results, a plausible reaction mechanism was also proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Methyl benzoate derivatives interact with SCA[6] to form stable inclusion complexes. • ESIPT and TICT processes are clearly different if the molecule migrates to hydrophobic nanocavity. • 1:1 complex is formed for I -SCA[6] and II -SCA[6] systems, while the stoichiometry of the III -SCA[6] and IV -SCA[6] is 1:2. • Solvation dynamics of pure water is markedly different from that of confined water molecule in SCA[6] system. This paper is a continuation of our previous research and aims to further investigate and elucidate the nature and mechanisms of noncovalent supramolecular interactions between four methyl benzoate derivatives (I - IV), which are capable of exhibiting Twisted Intramolecular Charge Transfer (TICT) and/or Excited State Intramolecular Proton Transfer (ESIPT)‐type behavior, and chemical and biological nanocavities. Photophysical and photochemical properties of molecules I - IV in aqueous solution in the presence of well-recognized macrocyclic host p -sulfocalix[6]arenes (SCA[6]) have been studied using steady-state, time-resolved and 1H NMR spectroscopic techniques. The changes in the ground- and excited-state spectroscopic characteristics (absorption and fluorescence spectra, time-resolved fluorescence spectra, fluorescence decay times and 1H NMR spectra) undergo significant modifications upon encapsulation of the investigated methyl benzoate derivative in the macromolecular cavity. For the two compounds (I and II), the interactions with the macrocycles with a hydrophobic SCA[6] cavity lead to the formation of stable inclusion complexes with 1:1 stoichiometry, both in the ground and excited state, while the stoichiometry of the III -SCA[6] and IV -SCA[6] complexes in the ground and excited states is 1:2. The values of the equilibrium constants have been determined from the spectroscopic data using Benesi-Hildebrand and nonlinear regression procedures. The location of the organic molecule inside the SCA[6] has been investigated by 1H NMR experiments. The changes in macrocyclic compound-induced NMR chemical shifts clearly indicate that the chemical structure of inclusion complexes is very different for methyl benzoate derivative-SCA[6] and methyl benzoate derivative-CB[7] systems. Finally, we have shown, using time-dependent fluorescence Stokes shift, that very fast solvation dynamics of pure water is markedly different from that of the confined water molecule in SCA[6] system. [ABSTRACT FROM AUTHOR]

• Research of methyl benzoates derivatives with CH 3 , OCH 3 , NO 2 , and Cl groups. • The spectral and physical characterizations of methyl benzoates derivatives. • Research of antioxidant, antibacterial and cytotoxic activities of them. • Investigation of bioactivity performances of methyl benzoates derivatives. In this study, the effects of electron-withdrawing or electron-releasing groups in methyl benzoate esters, which are widely used in the fragrance industry, on the antioxidant and antibacterial activities of the compounds were investigated. Firstly, methyl benzoates with electron-withdrawing (NO 2 and Cl groups) or electron-donating groups (CH 3 and OCH 3 groups) in the para position, which are commercial compounds, were synthesized, and extensively studied in terms of reaction conditions, and spectral data in their instrumental analysis methods. Then, the synthesized compounds were evaluated for their antioxidant, antibacterial, and cytotoxic activities. Among them, methyl 4-nitrobenzoate exhibited the highest inhibition against Staphylococcus aureus and Pseudomonas aeruginosa. Methyl 4-methoxybenzoate was selected for cytotoxicity evaluation due to its high antioxidant activity, and while the results indicated a dose-dependent decrease in cell viability, lower concentrations may still be considered for cosmetic applications. These findings suggest that antioxidant activity and cytotoxic activity are directly related to the electron density of the molecule. Therefore, this very up-to-date research covers many implications for organic chemistry, medicinal chemistry, biotechnology, and microbiology. Therefore, the results obtained may have great potential to be applied in the cosmetic industry and could be used as exceptionally useful information on alternative raw material selection for researchers in the fragrance industry. These results also suggest that methyl benzoates have potential as lead compounds for the development of novel antioxidant, antibacterial, and cytotoxic agents, but further studies are needed to fully explore their applications in various fields. [Display omitted] [ABSTRACT FROM AUTHOR]