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AbstractWe have developed a tandem reaction of ester-functionalized aziridines with secondary amines for the construction of isoindolin-1-ones. Its mechanism involves sequential ring opening of aziridines and lactamization. The novel features of this tandem reaction include high efficiency, broad substrate scope and mild conditions. [ABSTRACT FROM AUTHOR]

The article discusses the synthesis of aryl benzothiazole derivatives using microwave-assisted phase transfer catalysis, highlighting their potential as anticancer agents. Various synthetic methods and reactions are explored, with a focus on optimizing reaction conditions for high yields. The synthesized compounds are tested for anticancer activity against different cancer cell lines, showing promising results. The study aims to provide a convenient method for preparing aryl benzothiazoles and stimulate further research into their anticancer potential. [Extracted from the article]

Data on the occurrence of organophosphate tri-esters (tri-OPEs) and their metabolites (di-OPEs) in hen’s eggs are scarce. Therefore, 200 egg samples were gathered in 2023 in Hanoi, Vietnam and analysed by UHPLC-Q-Exactive HRMS. The majority of these compounds were detected, with tris(2-ethylhexyl) phosphate (0.10–2.7 ng/g wet weight (ww)) and trihexyl phosphate (0.08–2.3 ng/g ww) being the most prevalent tri-OPEs. Significant differences in tri-OPE profiles were observed in egg samples from battery-cage and free-range farming (p < .05). Despite egg levels ranging from 0.05 to 11.2 ng/g ww, Σdi-OPE accumulation in yolk and egg white was not significantly different in (p > .05). Among di-OPEs, dibutyl phosphate was found at the highest levels in the egg white, while bis(2-ethylhexyl) phosphate had the highest levels in yolk. There was no carcinogenic human health risk associated with OPEs in eggs (HQs <1). [ABSTRACT FROM AUTHOR]

An efficient one-step procedure for the synthesis of a new series of multifunctional olefins by condensation of α-substituted β-diketones as well as β-phosphonoesters and benzoylated β-ketoesters with formaldehyde, using potassium carbonate in refluxing THF, followed by a deacylation reaction, is herein described. In contrast, the α-substituted β-keto esters, bearing an acyl moiety, only undergo a hydroxymethylation reaction, with no metal catalysts/activating agents, as is usually required for the process, affording the corresponding α-hydroxymethyl β-keto esters in high yields. [ABSTRACT FROM AUTHOR]

Lawesson’s reagent reacted with racemic diethyl malate to yield O-(1,2-bis(ethylcarboxylate)ethyl-1 4-methoxyphenyl dithiophosphonic acid. The acid formed pyridinium dithiophosphonate salts with 3-(hydroxymethyl)pyridine, pyridoxine, and (S)-(–)-nicotine. The salts revealed antifungal activity against Candida albicans. [ABSTRACT FROM AUTHOR]

Metal triflate-catalyzed acylation of sulfonamides and direct transacylation of N-acylsulfonamides have been investigated. The acylation of sulfonamides proceeds efficiently in the presence of a catalytic amount of Cu(OTf)2 (0.001 equiv) using either carboxylic anhydrides or acyl chlorides as the acylating agents. Alternative catalysts suitable for this transformation include Al(OTf)3, Fe(OTf)3, Ga(OTf)3, In(OTf)3, and Er(OTf)3. In the presence of Cu(OTf)2 (0.2 equiv), N-acylsulfonamides undergo direct transacylation in excess acyl chlorides (10 equiv) to furnish new N-acylsulfonamides through exchange of N-acyl groups. Ga(OTf)3, Fe(OTf)3, and In(OTf)3 are similarly reactive in catalyzing such transacylation transformations. The reaction conditions are mild and operationally convenient. A variety of functional groups including halogeno, keto, nitro, cyano, ether, and carboxylic ester are tolerated, providing the corresponding monoacylated N-acylsulfonamides in good to excellent yields. [ABSTRACT FROM AUTHOR]

Recently, non-Saccharomyces yeasts have gained considerable attention as a novel strategy to enhance the aroma diversity of alcoholic beverages. This study explores the effect of sequential fermentations involving Lachancea thermotolerans and Torulaspora delbrueckii on the aroma profile of apple spirits. Additionally, the influence of time, temperature, and alcohol content on the volatile composition during the maturation of distillates was described. The results revealed that distillates obtained from mixed cultures exhibited improved aroma complexity, primarily due to increased ester production. Torulaspora delbrueckii positively influenced the synthesis of 2-phenethyl acetate, diethyl succinate, and hexyl acetate. Lachancea thermotolerans promoted the formation of ethyl lactate, ethyl myristate, and ethyl phenylacetate while reducing the concentration of higher alcohols. During maturation, changes in aroma constituents were observed. In general, the concentration of the investigated volatile compounds tends to decrease during maturation, with this trend being strongly related to the alcohol content of the distillates. Temperature did not affect the variations of methanol, acetaldehyde, 1-propanol, 2-butanol, 2-methyl-1-butanol, cis-2-hexen-1-ol, and diethyl succinate. Regarding esters, increases were observed in the concentration of ethyl octanoate, ethyl myristate, and, under certain circumstances, ethyl acetate and isoamyl acetate. No correlation was found between changes in acetaldehyde and the conditions tested. [ABSTRACT FROM AUTHOR]

Sucrose esters have been deployed as surfactants in many food products since the 1950s. In addition to their useful physical characteristics, sucrose esters also have interesting biological properties that enhance their utility. This review critically examines the broad suite of biological activities that has been attributed to both synthetically-derived and naturally-occurring sucrose esters. These include insecticidal, molluscicidal, plant growth-regulating, anti-microbial, anti-tumor, anti-oxidant, anti-depressive, neuro-protective, anti-inflammatory and anti-plasmodial effects. In addition to providing a summary of the structure-activity profiles of sucrose esters, the various known mechanisms-of action of these compounds are also discussed. Furthermore, since sucrose esters are well-known surfactants, the potential to advantageously apply their industrially desirable physical characteristics in combination with their biological properties is considered. Recent advances in synthetic chemistry that have facilitated the deployment of biologically active sucrose esters as food additives are also described. [ABSTRACT FROM AUTHOR]

This study investigates the transesterification of isoflavones puerarin and β-D-fructofuranosyl-(2→6)-puerarin to enhance their lipophilicity for specific pharmacological applications. The process achieved high yields (80-100%) in the isoflavones conversion when commercial lipases from Candida antarctica (CALB) and Thermomyces lanuginosus (TL IM) were used. The acylation patterns between CALB and TL IM varied depending on the substrate; both enzymes yielded principally monoacylated products from puerarin and β-D-fructofuranosyl-(2→6)-puerarin. However, TL IM also produced di- and triacylated derivatives of β-D-fructofuranosyl-(2→6)-puerarin in substantial amounts. Structural characterization by NMR identified puerarin-6ʹʹ-O-laurate and β-D-fructofuranosyl-(2→6)-puerarin-6ʹʹʹ-O-laurate as the primary products in CALB and TL IM reactions. These acyl derivatives presented improved lipophilicity (Log P from −1.0 − 0.16 to 3.26 − 3.58) and antioxidant activity (67.2-97.3 to 102.5-131.4 µM TE/mmol). Therefore, these compounds have potential pharmacological applications. [ABSTRACT FROM AUTHOR]

Purpose of the article: Interleukin-23 inhibitors, such as tildrakizumab, have emerged as safe and effective options for the management of psoriasis. Yet their efficacy in elderly patients (aged 65years or more), particularly in those with difficult-to-treat areas involvement, remains insufficiently explored. We conducted this real-life retrospective multicentric observational study to assess the effectiveness of tildrakizumab in elderly patients with moderate-to-severe psoriasis, with involvement of difficult-totreat areas. Materials and methods: We enrolled forty-nine patients aged 65years old or more (mean age 73.1±6.0), all treated with tildrakizumab for at least 28weeks. The effectiveness of tildrakizumab was assessed by Static Physician’s Global Assessment of Genitalia (sPGA-G), fingernail-PGA (f-PGA), palmoplantar PGA (pp-PGA), scalp-specific PGA (sc-PGA), and Psoriasis Area and Severity Index (PASI) scores. Results: Significant improvements in PASI scores were observed within 28weeks of treatment, with 77.5%, 60%, and 45.2% of patients achieving PASI75, PASI90, and PASI100, respectively. The mean PASI decreased significantly from baseline (13.6±9.9) to 1.3±1.7 at week 28. More than 90% of patients had clear sPGA-G and pp-PGA scores and over 70% had clear f-PGA and sc-PGA scores after 28weeks. Conclusions: Our findings suggest that tildrakizumab could be a valuable option for the treatment of elderly patients, including those with difficult-to-treat areas involvement. [ABSTRACT FROM AUTHOR]

The present study aimed to identify the content of astaxanthin and its esterified forms using high-performance liquid chromatography coupled with diode array and atmospheric pressure chemical ionisation mass spectrometry detection in three samples of shrimp waste. The analyses revealed twenty-one astaxanthin derivatives, including astaxanthin in free form, across all three extracts with the highest number of derivatives observed in the head extract. The shell extract had a lower content of astaxanthin and its esterified forms, with monoesterified astaxanthins being the major components, with contents ranging from 0.5–1 mg g−1. On the other hand, in both global waste and head extracts, astaxanthin diesters were found to be the dominant bioactive compounds, with contents ranging from 0.7–5.2 mg g−1 and 10.2–18.2 mg g−1, respectively. Notably, the astaxanthin content extracted from head was significantly higher compared to other extracts, indicating its potential as a valuable source of bioactive compounds. [ABSTRACT FROM AUTHOR]

Spinal cord ischemia has serious sequelae. The aim of this study is to investigate the effects of resveratrol and caffeic acid phenyl ester (CAPE), a propolis derivative, on spinal cord injury induced by ischemia-reperfusion (IR). In our research, 30 male Wistar albino rats, 200–250 gr, were used. Before the experiment, during a week of the process, the rats were fed with these two agents, and the experimental group rats were exposed to spinal cord IR injury. At the end of the experiment, spinal cord samples were taken from the sacrificed rats. Bax, p53, nNOS, and Beclin-1 immunoreactivity moreover TUNEL (+) cells were evaluated with immunohistochemically in the IR-induced damaged rats. It has been clearly determined that the TUNEL (+) apoptotic cell number and immunopositive cells of nNOS, Beclin-1, p53, Bax were raised in the IR group. However, these increments partially were restored in the resveratrol and CAPE-fed rats with IR-induced injury. In light of our data, resveratrol, and CAPE could be beneficial in spinal cord IR injury. Although both agents provide beneficial effects, it can be said that CAPE is partially more effective in spinal cord injury caused by IR. [ABSTRACT FROM AUTHOR]

Tyrosol is a principle phenolic compound present in olive oil and wine with great pharmacological potentials due to its strong antioxidant property. Its application can be highly extended by increasing its lipophilicity through esterification. In this study, tyrosol esters were synthesized by enzymatic transesterification of tyrosol with vinyl esters, with a commercial lipase from Novozymes (Novozym 435, Candida antarctica lipase B (CALB) immobilized on macroporous acrylic resin beads) as the catalyst, both in organic solvents and in ionic liquids. Methyl tert-butyl ether (MTBE) was the best solvent, offering complete conversions towards the synthesis of tyrosol esters with varying chain lengths (C2-C18) within 1 h. Taking the enzymatic transesterification between tyrosol and vinyl acetate as the model reaction, 18 organic solvents and 24 ionic liquids were screened, and their solvent properties (i.e. hydrophobicity, polarity, viscosity, water activity, and partition coefficients of substrate and product) were correlated to the enzyme activity. Upon enzyme screening, four new lipases were found to be highly efficient, relative to the best-performed Novozym 435 and Lipozyme TLIM (Thermomyces lanuginosus lipase (TLL) immobilized on silica gel), in tyrosol ester synthesis. This work provides enzymatic methods of esterifying tyrosol that are much more efficient than those reported in literature, and will shed light on re-consideration of the roles of solvents in nonaqueous enzymology. [ABSTRACT FROM AUTHOR]

AbstractA series of amino acid ester trifluoroacetate derivatives was synthesized from scaberol C. They were screened for their inhibitory activity against Non-Small Cell Lung Cancer (NSCLC) cells. Among them, compound 2 l showed significant cytotoxicity against A549 and H460 cells (IC50), and was more active than cisplatin (DDP). The epidermal growth factor receptor (EGFR) was overexpressed in NSCLC, which was the target of multiple cancer therapies and a strong prognostic indicator. Our previous studies reported that the target of scaberol C derivatives against NSCLC cells was EGFR. And then molecular docking analysis and molecular dynamics (MD) simulations indicated that 2 l can stably and covalently bind to the EGFR target protein. [ABSTRACT FROM AUTHOR]

The scent of Anacamptis species has been analyzed by using HS-SPME-GC–MS. The sample was collected in Basilicata (Southern Italy). Every species showed a different composition of the scent in the analyses we performed. 1,2,4-Trimethoxybenzene and methyl 4-mehoxybenzoate were the main components of that of Anacamptis coriophora subsp. fragrans. The scent of Anacamptis laxiflora was due to the presence of caryophyllene. Linear hydrocarbons but also decanal were components of the scent of Anacamptis pyramidalis. Eucalyptol was found in the scent of Anacamptis papilonacea. Finally, β-sesquiphellandrene was the main component of the scent of Anacamptis morio. [ABSTRACT FROM AUTHOR]

Exposure to organophosphate esters (OPEs) is associated with several chronic diseases, but the relationship with mortality risk is unclear. Therefore, we used the National Health and Nutrition Examination Survey 2011–2018 data to evaluate these relationships. 6,869 participants aged 18 years or older were included. Survival status information was obtained through the National Death Index through 31 December 2019. Multivariable COX regression model was adopted to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs) for the relationships of urinary OPEs metabolites with mortality risk. During an average of 5.0 years of follow-up, 406 deaths were documented. After adjusting for confounders, bis(2-chloroethyl) phosphate was associated with an increased risk of all-cause mortality [HR (95%CI) = 1.12(1.05–1.20)] and cardiovascular mortality [HR (95%CI) = 1.15(1.04–1.26)]. Our study found that exposure to OPEs was significantly associated with increased risks of all-cause and cardiovascular mortality. Consequently, controlling OPEs exposure is needed to alleviate the health-related burden. [ABSTRACT FROM AUTHOR]

This study presents a method based on acid transesterification and the purification by solid-phase extraction (SPE) coupled with gas chromatography–tandem mass spectrometry for quantifying 3- and 2-monochloropropanediol esters (3-MCPDE, 2-MCPDE) and glycidyl esters (GE) in nutritional foods. The fat was extracted by liquid–liquid extraction with petroleum ether and diethyl ether after the sample was hydrolysed with ammonia. Then the extract was purified by a SPE cartridge filled with the aminopropyl sorbents. It was demonstrated that the optimal elution volume for 3-MCPDE, 2-MCPDE and GE greatly depended on the sample matrix and varied from 6 to 12 mL for four different kinds of food matrices. All three analytes in the sample solution could be fully collected in the first 10–12 mL of eluate. By this way, monoacylglycerols commonly present in the samples were fully removed. Therefore, the overestimation of GE quantification was effectively eliminated. The modified analytical procedure was fully validated in a single laboratory and has been recommended as a Chinese Food Safety National Standard. In addition, two derivatisation agents, heptafluorobutyrylimidazole and phenylboronic acid, were proved to be equivalent in method accuracy and precision for the quantification of three analytes. [ABSTRACT FROM AUTHOR]

Ten novel 4-esterchalcones, licochalcone analogues, were strategically synthesized to study the effect of electro-donating or electro-withdrawing substituents in the aryl enone moiety on their pharmacological and photoprotective properties. 4-Esterchalcones had their drug-like character evaluated, which demonstrated positive characteristics for the development of novel drug candidates. In the in vitro antimicrobial evaluation, isovaleryl 4-esterchalcones showed activity against strains of Staphylococcus aureus, Candida albicans and C. tropicalis with minimum inhibitory concentration (MIC) in the range of 2.64-3.32 µmol mL−1, and the isobutyryl 4-esterchalcone 5d (4'-Br) presented antimicrobial activity against all strains tested, with a MIC of 2.74 µmol mL−1. In the UV-Vis study, λmax were observed at 312-327 nm, the UVB range, mainly. The best SPF-UVB results ranged from 18.04 to 21.06, with high εmax values, indicating that 4-esterchalcones have the potential to act as sunscreens. Furthermore, along with the environmental concern, halogenated compounds demonstrated slightly toxic on Artemia salina. [ABSTRACT FROM AUTHOR]

The instability of ester bonds, low water solubility, and increased cytotoxicity of flavonoid glycoside esters significantly limit their application in the food industry. Therefore, the present study attempted to resolve these issues through liposome encapsulation. The results showed that baicalin butyl ester (BEC4) and octyl ester (BEC8) have higher encapsulation and loading efficiencies and lower leakage rate from liposomes than baicalin. FTIR results revealed the location of BEC4 and BEC8 in the hydrophobic layer of liposomes, which was different from baicalin. Additionally, liposome encapsulation improved the water solubility and stability of BEC4 and BEC8 in the digestive system and PBS but significantly reduced their cytotoxicity. Furthermore, the release rate of BEC4 and BEC8 from liposomes was lower than that of baicalin during gastrointestinal digestion. These results indicate that liposome encapsulation alleviated the negative effects of fatty chain introduction into flavonoid glycosides. [ABSTRACT FROM AUTHOR]

The reaction products formed in the SO2 – ROH – (HOCH2)3CNH2 (where R – CH3, C2H5, n-C3H7, i-C3H7, n-C4H9 and n-C5H11) systems were isolated and identified as: binary salt – ammonium O-methylsulfite [(HOCH2)3CNH3]+ [CH3OSO2]− (1); 1/1 charge transfer complex between diethyl sulfite (2) and tris(hydroxymethyl)aminomethane by S-N binding; polymorhps of zwitterionic internal salt – O-sulfite tris(hydroxymethyl)methylammonium (at R – n-C4H9 and n-C5H11); and its solvates with n-propanol 1/1 (3) and isopropanol 2/1. The structures of all synthesized products were confirmed by FT-IR, Raman, 1H NMR and 13C NMR spectrometry, and the structure of 1 and 3 was characterized by crystal X-ray diffraction studies as well. [ABSTRACT FROM AUTHOR]

Designed to meet the specific needs of the printing industry exhaust gas emissions, this paper proposes a method for the degradation of gaseous acetic acid ester organics that is environmentally friendly, safe, and simple to use: micro-nano cavitation technology. In the process of using micro-nano cavitation technology to degrade acetic acid ester organics, the products in the degradation process were analyzed by gas chromatography-mass (GC-MS) spectrometry, and the degradation pathways of acetic acid ester organics were identified. Under high temperatures and high pressure caused by cavitation collapse, the C–C bond and C–O bond on the main chain of organic matter are cleaved to form low molecular products. Low-molecular intermediate products are continuously produced as the reaction advances, and these intermediate products are further oxidized and decomposed into carbon dioxide and water. Besides, the factors that influence the degradation rate of acetic acid ester organics were investigated. Based on the experimental data, acetic acid esters can degrade with the greatest efficiency when their initial concentration is 200 ± 50 mg/m3 and their treatment time is 20∼30 min. Moreover, the experiment was optimized using the response surface method. The results suggested that for an initial concentration of 155.544 mg/m3 and a reaction time of 21.961 min, the best degradation rate was 0.251 min−1. Micro-nano cavitation technology is a novel and promising technology for the degradation of volatile organic compounds, with a wide range of practical applications. [ABSTRACT FROM AUTHOR]

Glycidyl esters (GEs) and 3-monochloropropanediol esters (3-MCPDEs) are process contaminants commonly found in refined edible oils which are often added to infant formulas. The Taiwan Food and Drug Administration (TFDA) launched regulations for GEs in infant formulas that went into effect on 1 July 2021. To investigate levels of GEs and 3-MCPDEs in infant formula powder, 45 products were sampled and analysed during 2020–2021. The contents of GEs and 3-MCPDEs in formulas of different brands significantly varied, but their concentrations in all of the formulas complied with European Union (EU) regulations. Infant formulas containing palm oil had significantly higher 3-MCPDE levels in both extracted oils and milk powder than those without palm oil. Concentrations of GEs and 3-MCPDEs in infant formula powder and extracted oils were significantly lower in products from Europe than those from Australia and New Zealand. Infants aged 0–1 years in Taiwan who consumed only infant formula showed a margin of exposure (MoE) exceeding 25,000. Mean consumer exposures to 3-MCPDEs stayed below the tolerable daily intake (TDI), while high exposures at the 95th percentile (P95) exceeded the TDI by 1.7-fold. Herein, we present the changing trends in the risk assessment results of infant formula across various countries in the decade. Implementation of regulations and mitigation strategy effectively reduced the risk of infants being exposed to GEs and 3-MCPDEs through infant formula. [ABSTRACT FROM AUTHOR]

Two new monoterpene esters, illigerates H and I (1 and 2), and six known compounds actinodaphine (3), bulbocupnine (4), stephanine (5), hypserpanine B (6), betulinic acid (7) and gallic acid (8) were obtained from the root of Illigera paviflora Dunn. Their structures were elucidated by spectroscopic analysis. Anti-inflammatory and α-glucosidase inhibitory activity of some isolated compounds were assessed. Two monoterpenes 1 and 2 exhibited weak in vitro anti-inflammatory activity (IC50 64.5 ± 5.3 and 79.2 ± 7.5 μM) while compounds 3–6 showed inhibition of α-glucosidase with IC50 values ranged from 87.17 to 118.74 μM. [ABSTRACT FROM AUTHOR]

As a part of our systematic study on Castanopsis genus (Fagaceae), one new triterpene hydrolysable tannin (1) and two new phenol glucosides (2 and 3) were isolated from the leaves of Castanopsis eyrei (Champ. ex Benth.) Hutch. Compound 1 was identified as a triterpene hexahydroxydiphenoyl (HHDP) ester. This type of compounds has only been isolated from Castanopsis genus. The structures of 1-3 were elucidated by the combination of spectroscopic analysis (MS, 1 D and 2 D NMR) and chemical evidence. [ABSTRACT FROM AUTHOR]

Canna indica L. has been traditionally used to treat various diseases. Based on previously reported antithrombotic effect for this plant, two new phenylpropanoid sucrose esters (canindicoside A (1) and canindicoside B (2)) and seven known compounds: nepetoidin B (3), caffeic acid (4), ferulic acid (5), (R)-(+)-rosmarinic acid (6), isorinic acid (7), (S)-(-)-rosmarinic acid (8) and (S)-(-)-rosmarinic acid methyl ester (9) were isolated from the ethyl acetate extract. Compounds were elucidated by NMR and MS spectroscopic methods. The antiplatelet effect was evaluated using turbidimetric method. Anticoagulant activity was examined by measuring activated partial thromboplastine time (APTT), prothrombin time, and thrombine time (TT). It was shown for the first time that both new phenylpropanoid sucrose esters 1 and 2, 7 and 9 displayed dose-dependent antiplatelet effects. 2 and 9 had the highest inhibitory activity on both adenosine diphosphate (ADP)- and collagen-induced platelet aggregation. Moreover, 1, 7 and 9 also exhibited anticoagulant activity. At 0.4 mg/mL, both 1 and 7 prolonged APTT compared to the negative control (p < 0.05), suggesting the possible inhibitory impact on the intrinsic coagulation pathway. Moreover, 9 at 0.4 mg/mL exerted higher TT values than the negative control (p < 0.05). C. indica and its bioactive phytochemicals are potential candidates for development of anti-thrombosis therapy. [ABSTRACT FROM AUTHOR]

Chloropropanols and their esters are a group of food contaminants that have various toxicities to the human body. Research and control to chloropropanols and their esters is important to food safety. Therefore, the sensitive, accurate, precise, and effective determination of chloropropanols and their esters is highly essential to study their concentration, formation, and mitigation. The indirect method, commonly applied in the determination of chloropropanols and their esters, is based on the cleavage of ester bond, extraction, and derivatization. The conventional indirect method will still be the mostly used method in the near future due to its good sensitivity and feasibility, although its parameters need to be chosen and optimized according to sample stuffs and chloropropanol concentrations. Meanwhile, direct method and other quantitative methods should also be developed for special applications, such as studying the profile of chloropropanol esters and rapid screening protocol. The challenges and future perspectives of these methods are discussed in this review. This review can provide a reference on the selection, designation, and modification of methods for determining chloropropanols and their esters. [ABSTRACT FROM AUTHOR]

A substantial reduction in the cost of biodiesel production necessitates the identification of less expensive lipid-bearing substrates and a cost-effective process. The present study demonstrates the use of biomass suspension of Aspergillus sps. as a whole-cell catalyst for the generation of various alkyl esters from acid oil and cottonseed oil with different alcohols (methanol to decanol) as acyl acceptors. The yield of alkyl esters increased from methanol (79%) to pentanol (87%), followed by a decrease from hexanol (80%) to decanol (55%) in the case of acid oil. The extent of transesterification was significantly higher [P < 0.05] in case of acid oil, with most of the acyl acceptors as compared to cottonseed oil. The study reveals the potential use of biomass suspension of fungus as a catalyst and acid oil as an alternative, low-cost bearing, and quality feedstock for the generation of biodiesel for a diverse variety of industrial/commercial use. [ABSTRACT FROM AUTHOR]

A pair of new guaiane-type sesquiterpene tautomers (1) was isolated from rhizomes of Acorus calamus. Meanwhile, three pairs of known compounds, including a pair of dihydroflavone glycoside tautomers (2), a pair of 4-hydroxybenzoic acid ester glycoside tautomers (3), as well as a pair of secoiridoid glycoside tautomers (4) were isolated from fruits of Cornus officinalis. Their structures were elucidated by extensive spectroscopic and computational methods. Furthermore, the tautomeric mechanisms were discussed. [ABSTRACT FROM AUTHOR]

In the traditional production of acetic esters, water generated in the esterification reaction can form azeotropes with the ester or the unreacted alcohol, which requires subsequent multi-step distillation or extraction to purify the esters. A large number of intermediate streams in the separation process need to consume a lot of steam to obtain high-purity acetic esters, resulting in a high total energy consumption. In this review, a new extraction separation and purification technology, namely the salting-out effect for the purification of acetic esters, was summarized. Different salting-out agents were used to reduce the concentration of water/alcohols in the ester phase and increase the selectivity coefficient of esters to minimize energy consumption. The scaled particle theory provides a clear guideline for the baseline on the separation goal of the alkyl acetate/alcohol/water systems. Extractive distillation, reactive distillation, azeotropic distillation, pervaporation, adsorption, salting-out assisted distillation, and hybrid salting-out-distillation were compared to assess their advantages and disadvantages. Energy-saving production and separation of acetic esters can be achieved with the hybrid salting-out-distillation process because the salting-out agents are cheap, non-toxic, and non-volatile, and the salting-out process can be conducted at room temperature. [ABSTRACT FROM AUTHOR]

A number of {[4-(diethoxyphosphoryl)-2-R-1,3-oxazol-5-yl]amino}alkyl methanesulfonates were synthesized and the peculiarities of their reaction with triethylamine were studied. The influence of the structure of the 5-alkanolamine substituent on the efficiency of their transformation into 7-R-1-ethoxy-5-methyl-1,3,4,5-tetrahydro-1λ5-[1,3]oxazolo[4,5-c][1,5,2]oxazaphosphepine-1-ones was clarified. The structure of the [1,3]oxazolo[4,5-c][1,5,2]oxazaphosphepine derivatives has been reliably proven by elemental analysis, IR, 1H, 13C, and 31P NMR spectroscopy (including 1D and 2D experiments), mass spectrometry and single crystal X-ray diffraction. The oxazole cycle in [1,3]oxazolo[4,5-c][1,5,2]oxazaphosphepines is easily cleaved by water in an acidic environment, which leads to the formation of derivatives of the new heterocyclic system – N-(2-ethoxy-5-methyl-2-oxido-4-oxo-1,5,2-oxazaphosphepan-3-yl)arylamides. [ABSTRACT FROM AUTHOR]

Boronic acids/esters have recently emerged in the field of medicinal and pharmaceutical research due to their exceptional oxophilicity, low toxicity, and unique structure. They are known as potent enzyme inhibitors, cancer therapy capture agents, and can mimic certain types of antibodies to fight infections. They have been designed and developed into drugs, and this approach has emerged in the last 20 years. Five boronic acid drugs have been approved by the FDA and Health Canada, two of which are used to treat cancer, specifically multiple myeloma. The purpose of this review is to investigate boronic acid/ester derivatives as potential pharmaceutical agents as well as the mechanism of action. It will concentrate on six types of cancer: multiple myeloma, prostate cancer, breast cancer, lung cancer, cervical cancer, and colon cancer. Some newly developed boron-containing compounds have already demonstrated highly promising activities, but further investigation is required before final conclusions can be drawn. [ABSTRACT FROM AUTHOR]

A series of novel 2-oxo-2-(arylamino)ethyl 4-formylbenzoates were prepared via the reaction of the potassium salt of p-formylbenzoic acid with 2-chloro-N-aryl-acetamide in DMF at reflux. A new series of 1,4- dihydropyridin-3,5-dicarbonitriles, hexahydroacridine-1,8-diones, decahydropyrimido[4,5-b]quinolines, and hexahydrobenzo[4,5]imidazo[2, 1-b]quinazolines which are linked to N-aryl-benzoyloxyacetamide were obtained through the Hantzsch reaction of various 2-oxo-2-(arylamino)ethyl 4-formylbenzoate with the respective 3-aminocrotononitrile or a mixture of 1,3-dicarbonyl compounds and amine source. The structures of the novel compounds were confirmed using a variety of spectra. [ABSTRACT FROM AUTHOR]

The presence of 3-monochloropropane-1,2 diol ester (3-MCPDE) and glycidyl ester (GE) in processed palm oils is of concern, as these oils are widely used for edible purposes. The mitigation method studied here optimizes the removal of chloride through water washing of crude palm oil (CPO), to limit the formation of 3-MCPDE. The contaminant removal obtained via washing CPO supports the quantitative findings. By utilizing 5% water in the washing step, water-soluble chlorides in CPO are removed by up to 76%, resulting in a 71% reduction of 3-MCPDE to within statutory limits. In this study, a linear correlation was developed between the chloride and the corresponding 3-MCPDE with a correlation coefficient (R2) of 0.99. Using the correlations, 1.0 mg/kg of 3-MCPDE in refined, bleached and deodorized palm oil (RBDPO) will be obtained from CPO with 1.2 mg/kg chloride with 7% wash water usage. The study also showed minor GE reduction between 7 and 11% was attained after water washing. [ABSTRACT FROM AUTHOR]

In this work, a novel series of N and S-alkylated derivatives of 1-phenyl tetrazole-5-thione were synthesized by Michael addition in organic salt media TBAB (Tetrabutylammonium bromide) using inorganic base K2CO3 under solvent-free conditions. The new and conveniently synthesized products showed unusual regioselectivity during the reaction. S-Michael adducts via reaction between 1-phenyl tetrazole-5-thione and acrylic esters as well as acrylonitrile were afforded at room temperature and N-Michael adducts obtained at 70°C. Both reactions occurred within 24 h. Surprisingly, using fumarate esters as Michael acceptor proceeded a SN2 reaction at 100°C due to steric effects. The structures of products all were confirmed by 1H and 13C NMR spectra and target compound yields were good to excellent. [ABSTRACT FROM AUTHOR]

This study aims to investigate the optimized lipase-catalysed esterification reaction from novel feedstock microalgae (Chlorella protothecoides) oil-free fatty acids (FFAs) for biolubricant (Trimethylolpropane (TMP)-triesters) synthesis. FFAs were obtained from microalgae oil by enzymatic hydrolysis. Response surface methodology (RSM) with the central composite design was performed to investigate the effect of experimental factors (lipase amount, TMP/FFAs molar ratio, reaction temperature) on the FFAs conversion and also investigated to resolve the optimum design points. After the experimental studies, the highest FFAs conversion of 93% with 92% triester and 8% mono, di esters contents were found when the lipase amount was 5.5%. TMP/FFAs molar ratio was 0.33 and the reaction temperature value was 60°C. The model fitted with the experimental values with R2 = 0.97. It was also supported by gas chromatography and FTIR analyses that the product obtained was a lubricant. [ABSTRACT FROM AUTHOR]

Two new ester alkaloids were isolated from Portulaca oleracea L., identified as (5-aminofuran-2-yl) methyl acetate (1) named oleracone N and 4(S)-ethyl 3-acetamido-3-(dihydroxyamino) propanoate (2) named oleracone O. The structures were elucidated via spectroscopic methods, including 1 D and 2 D NMR, UHPLC-ESI-QTOF/MS and CD spectrometry technique. It was suggested that both oleracone N and oleracone O could significantly inhibit inflammatory factors IL-1β and TNF-α in RAW 264.7 cells induced by LPS. [ABSTRACT FROM AUTHOR]

Two new monoterpene esters (1 and 2) and four known compounds (3–6) were isolated from the pericarps of Alpinia zerumbet. Their structures were elucidated by extensive spectroscopic analyses and their anti-inflammatory activity was evaluated by monitoring their inhibitory effects on the interleukin-1β-induced production of nitric oxide in primary cultured rat hepatocytes. The new compound 1 and cardamonin 3 showed inhibitory activities with IC50 values of 17.6 ± 1.1 and 10.2 ± 1.3 µM, respectively, which are comparable to that of the positive control NG-methyl-L-arginine acetate salt. [ABSTRACT FROM AUTHOR]

Metabolites of the fungus Cunninghamella echinulata NRRL 1382 were investigated under the effect of fusidic acid (1) feeding. In addition to ergosterol (2) which is a fungal sterol, two novel adipate esters (3, 4) were isolated, and their structures were fully investigated using various spectroscopic analyses, including 1 D, 2 D NMR and HRESIMS. In silico biological target prediction and molecular docking investigation revealed a potential agonist/antagonist activity for compound 3 by binding to µ opioid receptor and antidiabetic effect by aldose reductase inhibitory activity for compound 4. [ABSTRACT FROM AUTHOR]

An efficient, highly convergent route for the synthesis of novel fourteen single isomer derivatives of ethyl-2-methyl-4-(pyridin-2-yl)-4H-benzo[4,5]thiazolo[3,2-a]pyrimidine-3-carboxylate have been developed by one-pot, three-component reaction between pyridine 2-aldehyde, β-ketoester and various derivatives of 2-amino benzothiazole in the presence of D-(+)-10-camphorsulphonic acid (D-(+)-10-CSA) as an effective chiral acid catalyst. Under the optimized conditions with 20 mol% catalyst loading, a wide range of optically active 4H-pyrimido[2,1-b]benzothiazole derivatives were obtained in good yields (up to 82%) with good to excellent enantioselectivities (84-99%ee). Their structures were elucidated by various spectroscopic methods such as 1H-NMR, 13C-NMR, Chiral HPLC, mass and elemental analysis. The attractive feature of this approach is one-pot synthesis, good yield, environment benign, mild reaction condition, simple, efficient, excellent stereoselectivity, water soluble catalyst and easy workup. All the final scaffolds have been screened for antibacterial activity. Among them, 4a', 4c', 4d', 4e', 4f', 4g', 4j',4m' and 4n' were proven to possess enhanced antibacterial properties as compared to the standard drug. [ABSTRACT FROM AUTHOR]

Esters of 2- and 3-monochloropropanediol (2-MCPDE, 3-MCPDE) and glycidol (GE) are regarded as process contaminants that are found in refined vegetable oils and oil-based foods. Since glycerol is produced during fat splitting, saponification and biodiesel production, it is important to have methods for determining contaminants that might be formed during these processes. Due to the use of glycerol as a food additive, data on the presence of compounds of toxicological concern, including 3-MCPD, are of interest. This study focuses on modifying the indirect analysis of 2-MCPDE, 3-MCPDE and GE using GC-MS based on the AOCS Official Method Cd 29a-13, validating the modified method, and quantifying 2-MCPDE, 3-MCPDE and GE in glycerol. The AOCS Cd 29a-13 method was modified at the initial stage of sample preparation in which the targeted esters were extracted from glycerol by vortex-assisted extraction before sample analysis. This modification was performed based on the polarity of all compounds involved. The calibration functions for all analytes were fitted to linear regression with R2 above 0.99. Limits of detection (LOD) 0.02, 0.01 and 0.02 mg kg−1 were obtained for 2-MCPDE, 3-MCPDE and GE, respectively. Spiked glycerol with 3-MCPDE and 2-MCPDE (0.25, 0.51 and 1.01 mg kg−1) and GE (0.58, 1.16 and 2.32 mg kg−1) were used for recovery and precision measurements. Recoveries of 100-108%, 101-103%, and 93-99% were obtained for 2-MCPDE, 3-MCPDE and GE, respectively. Acceptable precision levels with relative standard deviations ranged from 3.3% to 8.3% were obtained for repeatability and intermediate precision. The validated method was successfully applied for the analysis of the target compounds in refined glycerol from commercial plants, which showed that 2-MCPDE, 3-MCPDE and GE levels in the analysed samples were below the detection limit. [ABSTRACT FROM AUTHOR]

This brief and personal essay discusses Ester Hernández's and Astrid Hadad's artistic relationship, which includes a beautiful friendship that spans time and space. In particular, and from an intimate vantage point, I read two of Hernández's images that feature Hadad, which the Mexican artist has displayed in her home in Mexico City, to ponder a larger question regarding contemporary cross-border feminist and genderqueer esthetics and relations. The queer kinship between these two artists, I humbly posit, extends to the fans that come out to support Hadad's shows when she performs in cities in the U.S. with large Latinx demographics, particularly in California. [ABSTRACT FROM AUTHOR]

In this article, we present the influence of substituents with different electron-donating (ED) powers on the coordination properties of bis(benzoyloxy)dimethylsilane (BDMS) on the MgCl2 support of Ziegler–Natta (ZN) catalysts through molecular simulation of different adsorption adducts. Thermodynamically, the most favourable adsorption structure was found with the diaminoborane substituent in a bridging mode on the (110) crystalline facet, representing a 37.63% increase at PBEh/TZVP in the adsorption strength of the original silyl ester. Generally, the higher the ED strength of the substituent, the higher the exergonicity of donor coordination. All of the new donors except those containing the nitro and formyl groups are preferably chemisorbed on the (110) surface. While the nitro, formyl, vinyl, and hydroxyl substitutions deteriorated the isotacticity of the polymer, a diaminoborane group was predicted to enhance the isotactic index by 306% relative to the original donor. Particularly, nitrophenyl could improve the isotactic index by 69% while its complexation remained in the thermodynamically controlled regime. Overall, the present DFT study demonstrated how a systematic exploration of substituents over a wide range of ED power can help in the design of new Lewis base donors for ZN catalysis. [ABSTRACT FROM AUTHOR]

Antiferroelectricity is a desirable property of liquid crystalline materials. Therefore, we synthesised and studied two new chiral rod-like mesogens with a molecular core based on two biphenyls connected via ester linkage, with the phenyl substituted by a fluorine atom. The studied mesogens are characterised by nuclear magnetic resonance spectroscopy and mass spectrometry analysis. They have methyl heptyl in the chiral chain and exhibit an antiferroelectric phase in a very broad temperature range. We investigated their mesomorphic properties and confirmed the phase identification by differential scanning calorimetry and broad-frequency dielectric spectroscopy measurements. Additionally, we compared the studied mesogens with previously synthesised analogous materials. Two mixtures were formulated using a base mixture and new mesogens. The helical pitch of the synthesised mesogens and formulated mixtures was estimated using the selective reflection method. [ABSTRACT FROM AUTHOR]

The rising concern about the presence of 3-monochloropropane 1,2 diol ester (3-MCPDE) and glycidyl ester (GE) in food has prompted much research to be conducted. Some process modifications and the use of specific chemicals have been employed to mitigate both 3-MCPDE and GE. Alkalisation using NaOH, KOH, alkali metals or alkaline earth metals and post sparging with steam or ethanol and short path distillation have shown simultaneous mitigation of 51-91% in 3-MCPDE and of 13-99% in GE, both contaminants achieved below 1000 µg/kg. Some of the mitigation methods have resulted in undesirable deterioration in other parameters of the refined oil. When the processed oil is used in food processing, it results in changes to 3-MCPDE and GE. Repeated deep frying above 170 °C in the presence of NaCl and baking at 200 °C with flavouring (dried garlic and onion), resulted in increased 3-MCPDE. Repeated frying in the presence of antioxidants (TBHQ, rosemary and phenolics) decreased 3-MCPDE in processed food. The GE content in foods tends to decline with time, indicating instability of GE's epoxide ring. [ABSTRACT FROM AUTHOR]

Objective: Growing interest in the metabolic state of ketosis has driven development of exogenous ketone products to induce ketosis without dietary changes. Bis hexanoyl (R)-1,3-butanediol (BH-BD) is a novel ketone ester which, when consumed, increases blood beta-hydroxybutyrate (BHB) concentrations. BH-BD is formulated as a powder or ready-to-drink (RTD) beverage; the relative efficacy of these formulations is unknown, but hypothesized to be equivalent. Methods: This randomized, observer-blinded, controlled, crossover decentralized study in healthy adults (n = 15, mean age = 33.7 years, mean BMI = 23.6 kg/m2) aimed to elucidate blood BHB and glucose concentrations before and 15, 30, 45, 60, 90 and 120 minutes following two serving sizes of reconstituted BH-BD powder (POW 25 g, POW 12.5 g), compared to a RTD BH-BD beverage (RTD 12.5 g), and a non-ketogenic control, all taken with a standard meal. Results: All BH-BD products were well tolerated and increased BHB, inducing nutritional ketosis (BHB ≥0.5 mM) after ∼15 minutes, relative to the control. BHB remained elevated 2 h post-consumption. The control did not increase BHB. Ketosis was dose responsive; peak BHB concentration and area under the curve (AUC) were two-fold greater with POW 25 g compared to POW 12.5 g and RTD 12.5 g. There were no differences in peak BHB and AUC between matched powder and RTD formulas. Blood glucose increased in all conditions following the meal but there were neither significant differences in lowest observed concentrations, nor consistent differences at each time point between conditions. These results demonstrate that both powdered and RTD BH-BD formulations similarly induce ketosis with no differences in glucose concentrations in healthy adults. [ABSTRACT FROM AUTHOR]

A Fe3O4@ Diaion HP‐2MG resin was used for separation-preconcentration and determination of trace Ni(II) as the 2‐(5‐bromo‐2‐pyridilazo)‐5‐(diethylamino)phenol (PADAP) chelate. Nickel determination was performed by high‐resolution–continuum source flame atomic absorption spectrometry (HR-CS FAAS). Among the parameters affecting the recoveries of Ni(II) on the Fe3O4@ Diaion HP-2MG, the pH, resin mass, and sample volume were optimized. The influence of matrix ions upon the analyte recovery was evaluated and the tolerance limit was determined for common ions. The Fe3O4@ Diaion HP-2MG resin was used 15 times without any degradation in performance. The limit of detection, the limit of quantification, and preconcentration factor were 15.0 µg L−1, 49.0 µg L−1, and 100 respectively. The accuracy of the developed method was validated by the analyzing certified reference materials (NIST 1573a tomato leaves and TMDA-64.3 fortified water). The developed procedure was applied to natural water and food samples. [ABSTRACT FROM AUTHOR]

Oxidative stress caused by the harsh microenvironment after implantation of an artificial graft with mismatching mechanical properties usually triggers inflammation responses, which have adverse impacts on tissue regeneration. For coping with these problems, in this work, bioactive fibrous scaffolds were developed from specially synthesized carboxylated poly(ester urethane)urea (PEUU) and gelatin (Gel) by encapsulating pterostilbene (Pte) for the first time. The prepared electrospun membranes exhibited self-adaptable mechanical properties with high elasticity owing to the bonded electrospun fibers, cross-linking network between PEUU and Gel, and the inherent flexibility of the PEUU polymer in the fibrous matrix. The PEUU/Gel/Pte electrospun membrane containing 7% Pte could promote in vitro proliferation of human umbilical vein endothelial cells, and regulate vascular smooth muscle cells with excellent antioxidant properties via free radical scavenging. In vivo results in a rat subcutaneous implantation model further demonstrated the positive effect of the specially prepared PEUU/Gel/Pte scaffold on both normal cell growth and anti-inflammatory by promoting cellularization and polarizing macrophages toward the M2 phenotype. These PEUU/Gel/Pte electrospun membranes with adaptability benefit to tissue regeneration by modulating inflammation responses, especially applications in vascular regeneration. [ABSTRACT FROM AUTHOR]

Esters of 2-monochloropropane-1,2-diol (2-MCPD), 3- monochloropropane-1,2-diol (3-MCPD), and glycidol are present in infant formulas, follow-on foods and similar compositions. They arise mainly from the vegetable oil content and may cause harmful effects in consumers. The contents of these substances in formulas were determined indirectly by converting the esters to the free form, followed by derivatization and analysis by gas chromatography-tandem mass spectrometry (GC-MS/MS). The validation results demonstrate that the method had sufficient specificity and adequate accuracy. The limits of detection (LOD) and limits of quantification (LOQ) for each of 2-MCPDE, 3-MCPDE, and GE were 1.5 and 5 µg/kg, respectively. Formula intake by children up to 36 months of age was surveyed, and the data was used to assess the risks due to 3-MCPD esters (3-MCPDE) and glycidyl esters (GE). The mean exposure dose of 3-MCPDE for different age groups ranged from 0.51 to 1.13 µg/kg bw per day. The corresponding mean GE exposure ranged from 0.031 to 0.069 µg/kg bw per day. Neither mean values nor the percentile 95% values of 3-MCPDE exposure doses exceed the recommended provisional maximum tolerable daily intake (PMTDI). [ABSTRACT FROM AUTHOR]

Thirty-three honey samples were collected between 2017 and 2018 in Kastamonu Province, in order to characterise the palynological and physico-chemical properties of the honey produced in the western Black Sea region of Türkiye. Melissopalynological characteristics of the honey samples were determined based on the total pollen number in 10 g (TPN-10 g) along with the pollen taxa diversity. The physicochemical properties of the samples including humidity ratio, volatile organic compounds, total phenolic content, fructose/glucose ratio and hydroxymethylfurfural (HMF) content were determined using a refractometer, gas chromatography coupled with mass spectrometry (GC–MS), ultraviolet-visible spectrometry and high-performance liquid chromatography, respectively. Melissopalynological analysis revealed that the honey samples contain 49 taxa, of which 18 were determined at family level and 31 were determined at genus level. The most common taxon was Castanea sativa while the other important taxa were Apiaceae, Asteraceae, Amaranthaceae, Boraginaceae, Brassicaceae, Fabaceae and Lamiaceae. Eleven out of 33 honey samples were monofloral and the remaining 22 samples were multifloral. According to the TPN-10 g results of the honey samples, the total number of pollens in 10 g of Kastamonu honey was between 1051 and 325 108 pollen grains. The moisture ratio was obtained between 11.9 and 18.9% while the fructose + glucose values were between 35.84 and 84.1 g/100 g. HMF content varied between 0.38 and 21.31 ppm while the total phenolic content varied between 39.6 and 138.8 mg GAE/100 g. The GC–MS analysis revealed that the samples contain compounds belonging to the groups of aldehydes, aliphatic acid and its esters, alcohols, hydrocarbons, flavonoids, carboxylic acid and esters, ketones, and sugars. [ABSTRACT FROM AUTHOR]

The reaction between active alkenes such as 2-pyridin-2-yl-methylene-malononitrile or ethyl-2-cyano-3-pyridin-2-yl-acrylate and acetylenic esters in the presence of KSeCN at room temperature provided a simple and efficient one-pot route for the synthesis of highly functionalized selenophenes. The reaction is characterized by mild conditions, short reaction time and tolerance to various functional groups and the products were fully characterized by multinuclear (1H, 13C, and 77Se) NMR spectroscopy. [ABSTRACT FROM AUTHOR]