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Dicarboxylic acids (DCAs) are essential for intermediate metabolism and are implicated in multiple processes associated with various diseases. Several DCAs contribute to energy metabolism, impact mitochondrial function, and play a crucial role in body function. However, the low abundance of some DCAs in various body fluids makes their quantification particularly challenging. Therefore, an extremely sensitive method is required to determine DCA level fluctuations in biological samples in different diseases. We developed and optimized an LC-MS/MS method to quantify DCAs. We achieved charge reversal of the compounds from negative to positive ionization through chemical derivatization with dimethylaminophenacyl bromide (DmPABr) targeting the carboxyl group (R-COOH) under mild basic conditions. Derivatization enhanced sensitivity, mass fragmentation, and chromatographic separation for LC-tandem mass spectrometric quantification. The method was analytically optimized and demonstrated excellent linearity for individual DCAs (R 2 >0.99), as well as an exceptionally lower limit of detection (LLOD<266 fg) and lower limit of quantification (LLOQ<805 fg) for all DCAs. Furthermore, most derivatized DCAs were stable at room temperature and after ten repeated freeze-thaw cycles. After DCA extraction and quantification detection, we found differences in their distribution in plasma and urine. The rank order for DCAs in plasma is C4>C6>C7>C9>C5>C8>C22, whereas in the urine sample, the order is C4>C7>C6>C9>C5>C8>C10. For longer chains (C > 16), their proportions were >10x higher in plasma than in urine. Our optimized method using LC-MS/MS enables the quantification of DCAs with excellent sensitivity. The method will help in future studies investigating dicarboxylic acids' crucial role in health and biomarker discovery studies using targeted metabolomics., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

This work demonstrated an innovative antimicrobial and biodegradable food packaging film CBDA-10-SA which was prepared by crosslinking a natural polyphenolic truxillic acid (cyclobutane-dicarboxylic acid, CBDA-10) and sodium alginate (SA). The CBDA-10-SA film exhibited improved tensile strength (148 MPa) and UV shielding capabilities. The maximum thermal decomposition temperature was achieved of 249 °C. Compared to SA film, CBDA-10-SA showed increased antibacterial activities. In food packaging test, the CBDA-10-SA inhibited the rapid growth of potential of hydrogen (pH) value, slowed down the weight loss, reduced total plate count (TPC) value of pork, and delayed the spoilage process of pork. Notably, CBDA-10-SA displayed remarkable degradability in soil, with 60 % degrading in four weeks. In this study, CBDA-10-SA showed enhanced physicochemical and mechanical properties compared to traditional SA film. Those improvements make it anticipated to be used in not only food packaging but also mechanical, pharmaceutical, and agricultural fields., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

A simple, accurate and precise method was developed for the simultaneous estimation of the bempedoic acid and ezetimibe in pure and tablet dosage form. The developed method was validated as per International Conference on Harmonization guidelines. The chromatographic separation was achieved isocratically on a Waters- C 18 , 250 × 4.6 mm, 5 μm column. Mobile phase containing K 2 HPO 4 -methanol in the ratio 60:40 in buffer at pH 4.3 was pumped through column at a flow rate of 1.0 ml/min. The temperature was maintained at 25°C. The optimized wavelength selected was 242 nm. The separation of bempedoic acid and ezetimibe showed retention times of 3.090 and 4.268 min respectively. The RSD values of the bempedoic acid and ezetimibe were 0.34 and 0.08 respectively. The accuracy of method was determined at three levels (50,100 and 150%). The percentage recovery was obtained as 100.0 and 100.0% for bempedoic acid and ezetimibe, respectively. The limits of determination and quantitation obtained from regression equations of bempedoic acid and ezetimibe were 1.065, 3.550 and 0.203, 0.677, respectively. The regression equation of bempedoic acid is y = 20,795x + 24,168, and it is y = 6,885.7x + 11,000 for ezetimibe. The retention times were decreased and the run time was decreased, so that the method developed is simple and economical that can be adopted for regular quality control tests in industry., (© 2024 John Wiley & Sons Ltd.)

Prokaryotic transcription factors (TFs) regulate gene expression in response to small molecules, thus representing promising candidates as versatile small molecule-detecting biosensors valuable for synthetic biology applications. The engineering of such biosensors requires thorough in vitro and in vivo characterization of TF ligand response as well as detailed molecular structure information. In this work, we functionally and structurally characterize the Pca regulon regulatory protein (PcaR) transcription factor belonging to the IclR transcription factor family. Here, we present in vitro functional analysis of the ligand profile of PcaR and the construction of genetic circuits for the characterization of PcaR as an in vivo biosensor in the model eukaryote Saccharomyces cerevisiae. We report the crystal structures of PcaR in the apo state and in complex with one of its ligands, succinate, which suggests the mechanism of dicarboxylic acid recognition by this transcription factor. This work contributes key structural and functional insights enabling the engineering of PcaR for dicarboxylic acid biosensors, in addition to providing more insights into the IclR family of regulators., (© 2024 The Authors. The FEBS Journal published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.)

Metabolites exploration of the ethyl acetate extract of Fusarium solani culture broth that was isolated from Euphorbia tirucalli root afforded five compounds; 4-hydroxybenzaldehyde (1), 4-hydroxybenzoic acid (2), tyrosol (3), azelaic acid (4), malic acid (5), and fusaric acid (6). Fungal extract as well as its metabolites were evaluated for their anti-inflammatory and anti-hyperpigmentation potential via in vitro cyclooxygenases and tyrosinase inhibition assays, respectively. Azelaic acid (4) exhibited powerful and selective COX-2 inhibition followed by fusaric acid (6) with IC 50 values (2.21 ± 0.06 and 4.81 ± 0.14 μM, respectively). As well, azelaic acid (4) had the most impressive tyrosinase inhibitory effect with IC 50 value of 8.75 ± 0.18 μM compared to kojic acid (IC 50  = 9.27 ± 0.19 μM). Exclusive computational studies of azelaic acid and fusaric acid with COX-2 were in good accord with the in vitro results. Interestingly, this is the first time to investigate and report the potential of compounds 3-6 to inhibit cyclooxygenase enzymes. One of the most invasive forms of skin cancer is melanoma, a molecular docking study using a set of enzymes related to melanoma suggested pirin to be therapeutic target for azelaic acid and fusaric acid as a plausible mechanism for their anti-melanoma activity., (© 2024. The Author(s).)

Purpose: Acne vulgaris is a chronic inflammatory skin disorder centered on hair follicles, making hair follicle-targeted delivery of anti-acne drugs a promising option for acne treatment. However, current researches have only focused on the delivering to healthy hair follicles, which are intrinsically different from pathologically clogged hair follicles in acne vulgaris., Patients and Methods: Azelaic acid (AZA) micro/nanocrystals with different particle sizes were prepared by wet media milling or high-pressure homogenization. An experiment on AZA micro/nanocrystals delivering to healthy hair follicles was carried out, with and without the use of physical enhancement techniques. More importantly, it innovatively designed an experiment, which could reveal the ability of AZA micro/nanocrystals to penetrate the constructed clogged hair follicles. The anti-inflammatory and antibacterial effects of AZA micro/nanocrystals were evaluated in vitro using a RAW264.7 cell model stimulated by lipopolysaccharide and a Cutibacterium acnes model. Finally, both the anti-acne effects and skin safety of AZA micro/nanocrystals and commercial products were compared in vivo., Results: In comparison to commercial products, 200 nm and 500 nm AZA micro/nanocrystals exhibited an increased capacity to target hair follicles. In the combination group of AZA micro/nanocrystals and ultrasound, the ability to penetrate hair follicles was further remarkably enhanced ( ER value up to 9.6). However, toward the clogged hair follicles, AZA micro/nanocrystals cannot easily penetrate into by themselves. Only with the help of 1% salicylic acid, AZA micro/nanocrystals had a great potential to penetrate clogged hair follicle. It was also shown that AZA micro/nanocrystals had anti-inflammatory and antibacterial effects by inhibiting pro-inflammatory factors and Cutibacterium acnes. Compared with commercial products, the combination of AZA micro/nanocrystals and ultrasound exhibited an obvious advantage in both skin safety and in vivo anti-acne therapeutic efficacy., Conclusion: Hair follicle-targeted delivery of AZA micro/nanocrystals provided a satisfactory alternative in promoting the treatment of acne vulgaris., Competing Interests: The authors report a patent CN116747147A pending, grants from Nanjing Miaobang Meiye Enterprise Management Co., Ltd. during the conduct of the study. The authors declare that they have no other conflicts of interest in this work., (© 2024 Ji et al.)

The cross-linked enzyme (CLEs) of Thermomyces lanuginosa lipase (TLL) was prepared in an isocyanide-based multi-component reactions (ICMRs) platform by applying three di-acidic cross-linkers to unveil more factors contributing to the functional properties of CLEs. The linkers were 1,11-undecanedicarboxylic acid, azelaic acid, and adipic acid with 11, 7, and 4 carbon lengths, respectively, providing a proper tool to investigate the effect of linker length on the activity, stability, and selectivity of the resulting CLEs. The immobilization yields of 60-90 % and the specific activities of 168, 88.4 and 49 U/mg were obtained for the CLEs of 1,11-undecanedicarboxylic acid, azelaic acid, adipic acid, respectively. The lower activity of azelaic and adipic acid-mediated CLEs compared to the soluble TLL (110 U/mg) was explained by in silico calculations. The results revealed that as opposed to 1,11-undecanedicarboxylic acid, both linkers tended to penetrate the enzyme active site, thus resulting in a major inhibitory effect on the enzyme functionality. The thermal and co-solvent stability of the immobilized derivatives improved compared to those of free TLL. The selectivity of CLEs was also examined by catalytic release of main omega-3 fatty acids from fish oil, presenting the highest selectivity of 22 for the CLEs of azelaic acid., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Polyesters from furandicarboxylic acid derivatives, i.e., dimethyl 2,5-furandicarboxylate (2,5-DMFDCA) and 2,4-DMFDCA, show interesting properties among bio-based polymers. Another potential heteroaromatic monomer, 3,4-bis(hydroxymethyl)furan (3,4-BHMF), is often overlooked but holds promise for biopolymer synthesis. Cleaning and greening synthetic procedures, i.e., enzymatic polymerization, offer sustainable pathways. This study explores the Candida antarctica lipase B (CALB)-catalyzed copolymerization of 3,4-BHMF with furan dicarboxylate isomers and aliphatic diols. The furanic copolyesters (co-FPEs) with higher polymerization degrees are obtained using 2,4-isomer, indicating CALB's preference. Material analysis revealed semicrystalline properties in all synthesized 2,5-FDCA-based co-FPEs, with multiple melting temperatures ( T m ) from 53 to 124 °C and a glass-transition temperature ( T g ) of 9-10 °C. 2,4-FDCA-based co-FPEs showed multiple T m from 43 to 61 °C and T g of -14 to 12 °C; one of them was amorphous. In addition, all co-FPEs showed a two-step decomposition profile, indicating aliphatic and semiaromatic segments in the polymer chains.

Field observations of daytime HONO source strengths have not been well explained by laboratory measurements and model predictions up until now. More efforts are urgently needed to fill the knowledge gaps concerning how environmental factors, especially relative humidity (RH), affect particulate nitrate photolysis. In this work, two critical attributes for atmospheric particles, i.e., phase state and bulk-phase acidity, both influenced by ambient RH, were focused to illuminate the key regulators for reactive nitrogen production from typical internally mixed systems, i.e., NaNO 3 and dicarboxylic acid (DCA) mixtures. The dissolution of only few oxalic acid (OA) crystals resulted in a remarkable 50-fold increase in HONO production compared to pure nitrate photolysis at 85% RH. Furthermore, the HONO production rates ( P HONO ) increased by about 1 order of magnitude as RH rose from <5% to 95%, initially exhibiting an almost linear dependence on the amount of surface absorbed water and subsequently showing a substantial increase in P HONO once nitrate deliquescence occurred at approximately 75% RH. NaNO 3 /malonic acid (MA) and NaNO 3 /succinic acid (SA) mixtures exhibited similar phase state effects on the photochemical HONO production. These results offer a new perspective on how aerosol physicochemical properties influence particulate nitrate photolysis in the atmosphere.

Recently, catalytic valorization of biomass-derived furans has received growing interest. 5-Aminomethyl-2-furancarboxylic acid (AMFC), a furan amino acid, holds great promise in the aeras of polymer and pharmaceutical, but its synthesis remains limited. In this work, we report a chemobiocatalytic route toward AMFC by combining laccase-TEMPO system and recombinant Escherichia coli (named E. coli&#95;TAF) harboring ω-transaminase (TA), L-alanine dehydrogenase (L-AlaDH) and formate dehydrogenase (FDH), starting from 5-hydroxymethylfurfural (HMF). In the cascade, HMF is oxidized into 5-formyl-2-furancarboxylic acid (FFCA) by laccase-TEMPO system, and then the resulting intermediate is converted into AMFC by E. coli&#95;TAF via transamination with cheap ammonium formate instead of costly organic amine donors, theoretically generating H 2 O and CO 2 as by-products. The tandem process was run in a one-pot twostep manner, affording AMFC with approximately 81 % yield, together with 10 % 2,5-furandicarboxylic acid (FDCA) as by-product. In addition, the scale-up production of AMFC was demonstrated, with 0.41 g/L h productivity and 8.6 g/L titer. This work may pave the way for green manufacturing of the furan-containing amino acid., (© 2024 Wiley‐VCH GmbH.)

Background: Bempedoic acid (BEM) belongs to a category of drugs known as Adenosine triphosphate-citrate Lyase (ACL) inhibitors. It is a prodrug with intracellular activation that is administered orally. Bempedoic acid is used to treat existing atherosclerotic cardiovascular diseases, mainly hypercholesterolemia., Methods: For the stability-indicating assay, the HPLC method was employed using a Kromasil 100-5-C8 column (100 mm × 4.6 mm), a UV detector set at 230 nm, and a mobile phase comprising a 70:30 v/v mixture of acetonitrile and 0.1% Orthophosphoric Acid (OPA) buffer. The method was operated at an ambient temperature with a flow rate of 1 mL/min. The method developed has been statistically validated according to ICH guidelines., Results: The stability-indicating method was executed using a Kromasil 100-5-C8 (100 mm × 4.6 mm) column at a 1.0 mL/min flow rate. A mixture of acetonitrile and 0.1% Orthophosphoric Acid (OPA) buffer in a 70:30 v/v ratio made up the mobile phase. BEM's retention times were discovered to be 1.88 minutes each. The temperature was kept at room temperature. 234 nm was the ideal wavelength for BEM. According to ICH criteria, the approach developed has undergone statistical validation. BEM's % RSD was discovered to be 0.6, respectively. For BEM, the % recovery was determined to be 100.0%. Regression models for bempedoic acid yielded LoD and LoQ values of 3.3 and 10.1 g/mL, respectively. The method showed good reproducibility and recovery with a % RSD less than 2. Studies on forced degradation confirmed the method's capacity to indicate stability in the presence of stress conditions, such as acid, basic, peroxide, UV, heat, and humidity. Both the retention times and the run time were shortened., Conclusion: In accordance with ICH Q2 (R1) guidelines, this method was successfully tested with HPLC to confirm the chemical structures of newly produced degradation products of bempedoic acid., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Pharmaceutical cocrystals use common robust hydrogen bonding synthons to create novel materials with different physicochemical properties. In this systematic study of a series of cocrystals, we explore the effect of high pressure on one of these commonly used motifs, the acid-pyridine motif, to assess the commonality of behaviour under extreme conditions. We have surveyed five pyridine dicarboxylic acid systems using both synchrotron and neutron diffraction methods to elucidate the changes in structure. We observe that the hydrogen bonding in these systems compress at a similar rate despite the changes to the molecular make-up of the solids and that on compression the changes in structure are indicative that the layers move along the major slip planes in the structure. We have observed two phase transitions to new forms of the pyrazine:malonic acid system, one for each stoichiometric ratio. This study demonstrates that the combination of two complementary diffraction approaches is key to understanding polymorphic behaviour at high pressure., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Iain D H Oswald reports financial support was provided by Engineering and Physical Sciences Research Council. Iain D H Oswald reports financial support was provided by Science and Technology Facilities Council. Iain D H Oswald reports a relationship with Science and Technology Facilities Council that includes: board membership, consulting or advisory, and travel reimbursement., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

The reluctance of a polyester with high glass transition temperature ( T g ) and mechanical properties to hydrolyze is a well-known fact, for instance, the high hydrolysis resistance of aromatic polyesters based on terephthalic acid and 2,5-furandicarboxylic acid (FDCA). The synthesis of polyesters that have a high T g (>100 °C) and a fast hydrolytic degradation quality at the same time is a valuable topic. Herein, a renewable rigid diester, N , N '- trans -1,4-cyclohexane-bis(pyrrolidone-4-methyl carboxylate) (CBPC), was obtained via Michael addition. CBPC was copolymerized with FDCA and ethylene glycol to prepare a series of copolyesters PEC x EF y with a high M n over 30 kDa. PEC x EF y showed a T g range of 75.2-109.2 °C which outdistanced the most biobased polyesters. The thermal stability of all PEC x EF y remained unchanged with the introduction of CBPC. Moreover, PEC x EF y presented superior mechanical performances which were matching or exceeding those of commercial polyethylene terephthalate (PET) and polylactic acid (PLA). PEC x EF y was stable in air but was able to undergo noticeable hydrolytic degradation, proving their enhanced degradability. And the regulation between CBPC and FDCA composition can be leveraged to adjust the degradation and environmental durability of PEC x EF y , up to practical applications. Computational studies systematically revealed the relationship between CBPC with a tricyclic structure and the improved T g and hydrolyzation properties. The outstanding thermal and mechanical performances and hydrolysis of these copolyesters appear to be promising candidates for renewable alternatives to industrial petrochemical polyesters.

The partitioning of semivolatile organic compounds (SVOCs) between the condensed and gas phases can have significant implications for the properties of aerosol particles. In addition to affecting size and composition, this partitioning can alter radiative properties and impact cloud activation processes. We present measurements and model predictions on how activity and pH influence the evaporation of SVOCs from particles to the gas phase, specifically investigating aqueous inorganic particles containing dicarboxylic acids (DCAs). The aerosols are studied at the single-particle level by using optical trapping and cavity-enhanced Raman spectroscopy. Optical resonances in the spectra enable precise size tracking, while vibrational bands allow real-time monitoring of pH. Results are compared to a Maxwell-type model that accounts for volatile and nonvolatile solutes in aqueous droplets that are held at a constant relative humidity. The aerosol inorganic-organic mixture functional group activity coefficients thermodynamic model and Debye-Hückel theory are both used to calculate the activities of the species present in the droplet. For DCAs, we find that the evaporation rate is highly sensitive to the particle pH. For acidity changes of approximately 1.5 pH units, we observe a shift from a volatile system to one that is completely nonvolatile. We also observe that the pH itself is not constant during evaporation; it increases as DCAs evaporate, slowing the rate of evaporation until it eventually ceases. Whether a DCA evaporates or remains a stable component of the droplet is determined by the difference between the lowest p K a of the DCA and the pH of the droplet.

The current work was aimed at the development of a topical drug delivery system for azelaic acid (AzA) for acne treatment. The systems tested for this purpose were deep eutectic systems (DESs) prepared from choline chloride (CC), malonic acid (MA), and PEG 400. Three CC to MA and eight different MA: CC: PEG400 ratios were tested. The physical appearance of the tested formulations ranged from solid and liquid to semisolid. Only those that showed liquid formulations of suitable viscosity were considered for further investigations. A eutectic mixture made from MA: CC: PEG400 1:1:6 (MCP 116) showed the best characteristics in terms of viscosity, contact angle, spreadability, partition coefficient, and in vitro diffusion. Moreover, the MCP116 showed close rheological properties to the commercially available market lead acne treatment product (Skinorin ® ). In addition, the formula showed synergistic antibacterial activity between the MA moiety of the DES and the AzA. In vitro diffusion studies using polyamide membranes demonstrated superior diffusion of MCP116 over the pure drug and the commercial product. No signs of skin irritation and edema were observed when MCP116 was applied to rabbit skin. Additionally, the MCP116 was found to be, physically and chemically, highly stable at 4, 25, and 40 °C for a one-month stability study.

FtpM from Aspergillus fumigatus was the first carboxyl methyltransferase reported to catalyse the dimethylation of dicarboxylic acids. Here the creation of mutant R166M that can catalyse the quantitative conversion of bio-derived 2,5-furandicarboxylic acid (FDCA) to its dimethyl ester (FDME), a bioplastics precursor, was reported. Wild type FtpM gave low conversion due to its reduced catalytic efficiency for the second methylation step. An AlphaFold 2 model revealed a highly electropositive active site, due to the presence of 4 arginine residues, postulated to favour the binding of the dicarboxylic acid over the intermediate monoester. The R166M mutation improved both binding and turnover of the monoester to permit near quantitative conversion to the target dimethyl ester product. The mutant also had improved activity for other diacids and a range of monoacids. R166M was incorporated into 2 multienzyme cascades for the synthesis of the bioplastics precursor FDME from bioderived 5-hydroxymethylfurfural (HMF) as well as from poly(ethylene furanoate) (PEF) plastic, demonstrating the potential to recycle waste plastic., (© 2023 The Authors. ChemSusChem published by Wiley-VCH GmbH.)

As an alternative to petrochemical synthesis, well-established industrial microbes, such as Escherichia coli , are employed to produce a wide range of chemicals, including dicarboxylic acids (DCAs), which have significant potential in diverse areas including biodegradable polymers. The demand for biodegradable polymers has been steadily rising, prompting the development of efficient production pathways on four- (C4) and five-carbon (C5) DCAs derived from central carbon metabolism to meet the increased demand via the biosynthesis. In this context, E. coli is utilized to produce these DCAs through various metabolic engineering strategies, including the design or selection of metabolic pathways, pathway optimization, and enhancement of catalytic activity. This review aims to highlight the recent advancements in metabolic engineering techniques for the production of C4 and C5 DCAs in E. coli .

Semi-aromatic polyamides (SAPs) synthesized from petrochemical diacids and diamines are high-performance polymers that often derive their desirable properties from a high degree of crystallinity. Attempts to develop partially renewable SAPs by replacing petrochemical diacids with biobased furan-2,5-dicarboxylic acid (FDCA) have resulted in amorphous materials or polymers with low melting temperatures. Herein, we report the development of poly(5-aminomethyl-2-furoic acid) (PAMF), a semicrystalline SAP synthesized by the polycondensation of CO 2 and lignocellulose-derived monomer 5-aminomethyl-2-furoic acid (AMF). PAMF has glass-transition and melting temperatures comparable to that of commercial materials and higher than that of any previous furanic SAP. Additionally, PAMF can be copolymerized with conventional nylon 6 and is chemically recyclable. Molecular dynamics (MD) simulations suggest that differences in intramolecular hydrogen bonding explain why PAMF is semicrystalline but many FDCA-based SAPs are not.

The crystal structures of four novel dicarboxylic acid salts of ciprofloxacin (CFX) with modified physicochemical properties, prepared by mechanochemical synthesis and solvent crystallization, are reported. A series of dicarboxylic acids of increasing molecular weight was chosen, predicted to interact via a carboxylic acid:secondary amine synthon. These were succinic (SA), glutaric (GA), adipic (AA) and pimelic (PA) acids (4, 5, 6, 7 carbon atoms respectively). Characterized by single crystal and powder X-ray diffraction, Fourier-Transform Infrared Spectroscopy, thermogravimetric analysis, differential scanning calorimetry, scanning electron microscopy and aqueous solubility measurements, these salts showed distinct physicochemical properties relative to ciprofloxacin base. Searches of the Cambridge Structural Database (CSD) confirmed CFX-SA, CFX-GA, CFX-AA and CFX-PA to be novel crystal structures. Furthermore, the GA salt has substantially higher solubility than the widely available hydrochloride monohydrate salt (CFX-HCl·H 2 O). CFX-SA, CFX-GA and CFX-AA showed minimum inhibitory concentration (MIC) of 0.008 g/L and CFX-PA showed MIC of 0.004 g/L. The prepared CFX salts retained antibacterial activity exhibiting equivalent antimicrobial activity to CFX-HCl·H 2 O. These salts have positive implications for increasing the application of CFX beyond conventional oral formulations and highlight mechanochemical activation as suitable production method., Competing Interests: Conflict of Interest Disclosure The authors declare no conflict of interest., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

A series of poly(hexamethylene 2,5-furandicarboxylate- co -2,6-naphthalate) copolyesters were synthesized using various amounts of poly(hexylene 2,5-furandicarboxylate) (PHF) and poly(hexylene 2,6-naphthalate) (PHN) via melt polymerization. The effects of introducing 2,6-naphthalene dicarboxylic acid (NDCA) on the thermal, mechanical, and gas-barrier properties were investigated. When the NDCA content was less than 30 mol%, the temperatures of crystallization ( T c ) and melting ( T m ) decreased as the amount of NDCA was increased owing to disturbance of the polymer-chain regularity. When the NDCA content was above 50 mol%, the T c and T m of the materials increased as the NDCA content was increased, showing that the dominant crystallization behavior varied from 2,5-furandicarboxylic acid to NDCA. Hence, the glass transition temperature ( T g ) increased as the NDCA content was increased, which was attributed to the incorporation of NDCA with a more rigid naphthalate structure compared with the furan ring. The gas-barrier properties of the samples were observed to improve with the introduction of NDCA; this tendency could be explained by the β-relaxation behavior and free volume values of the samples in the amorphous state. The activation energy ( E a ) of β-relaxation increased with the NDCA content, indicating that higher amounts of energy were needed to trigger the onset of long-range molecular motions. Free-volume calculations of the polymer structure showed that the introduction of NDCA hindered the space for gas penetration. For these reasons, the gas-barrier properties were improved and evaluated.

Depletion of chloride, nitrate, or ammonium from atmospheric aerosols represents a unique class of displacement reactions in which strong acids (HCl and HNO 3 ) or bases (NH 3 ) are substituted by weaker ones (i.e., dicarboxylic acids or dicarboxylate salts, respectively). These reactions alter the aerosol composition and perturb the atmospheric cycle of volatile compounds, thereby affecting environmental systems and climate. Despite the profound implications, the mechanism of these unique displacement reactions remains unclear. Here, we elucidate the thermodynamics and kinetics of these reactions using the multiphase buffer theory and a diffusion-controlled mass-transfer function, respectively. On the thermodynamic aspect, we find that the effective dissociation constants of the strong acids and bases in aerosols are 2 to 10 orders of magnitude lower than those in bulk solutions. On the kinetic aspect, we find that displacement reactions occur rapidly in aerosol microdroplets with a radius below 10 μm. Within this size range, the characteristic reaction time is always shorter than the lifetime of the aerosols in the atmosphere. Our findings suggest that the unique displacement reactions can significantly modify the composition of atmospheric aerosols, and consequentially, these aerosols may manifest distinct properties unforeseen by the chemistry of homogeneous bulk systems.

The selective photo-oxidation of biomass-derived 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) is important due to its substitute-role in polyester-fabrication. Here, a titanium-cluster based metal-covalent organic framework nanosheet has been synthesized through the covalent-coupling between Ti 6 -NH 2 and benzotrithiophene tricarbaldehyde (BTT). The integration of them endows the nanosheet with a visible-light-adsorption region, effective electron-hole separation-efficiency and suitable photo-oxidation ability. Specifically, its photo-selectivity for HMF-to-FDCA can be >95 % with ≈100 % conversion, which is more than 2, 5, and 10 times higher than MOF-901 (43 %), Ti 6 -NH 2 (19 %) and under-darkness (9 %), respectively. Notably, an O 2 -based mechanism is proposed and the vital roles of Ti 6 -NH 2 and BTT are verified by DFT calculations. This work might facilitate the exploration of porous-crystalline-catalysts for selective biomass-valorization., (© 2022 Wiley-VCH GmbH.)

In recent years, electrocatalysis was progressively developed to facilitate the selective oxidation of biomass-derived 5-hydroxymethylfurfural (HMF) towards the value-added chemical 2,5-furandicarboxylic acid (FDCA). Among reported electrocatalysts, alloy materials have demonstrated superior electrocatalytic properties due to their tunable electronic and geometric properties. However, a specific discussion of the potential impacts of alloy structures on the electrocatalytic HMF oxidation performance has not yet been presented in available Reviews. In this regard, this Review introduces the most recent perspectives on the alloy-driven electrocatalysis for HMF oxidation towards FDCA, including oxidation mechanism, alloy nanostructure modulation, and external conditions control. Particularly, modulation strategies for electronic and geometric structures of alloy electrocatalysts have been discussed. Challenges and suggestions are also provided for the rational design of alloy electrocatalysts. The viewpoints presented herein are anticipated to potentially contribute to a further development of alloy-driven electrocatalytic oxidation of HMF towards FDCA and to help boost a more sustainable and efficient biomass refining system., (© 2022 Wiley-VCH GmbH.)

Artificial biorefinery of oleic acid into 1,10-decanedioic acid represents a revolutionizing route to the sustainable production of chemically difficult-to-make bifunctional chemicals. However, the carbon atom economy is extremely low (56%) due to the formation of unifunctional n -octanol. Here, we report a panel of recombinant Escherichia coli modules for diverse bifunctionalization, where the desired genetic parts are well distributed into different modules that can be flexibly combined in a plug-and-play manner. The designed ω-functionalizing modules could achieve ω-hydroxylation, consecutive ω-oxidation, or ω-amination of n -octanoic acid. By integrating these advanced modules with the reported oleic acid-cleaving modules, high-value C8 and C10 products, including ω-hydroxy acid, ω-amino acid, and α,ω-dicarboxylic acid, were produced with 100% carbon atom economy. These ω-functionalizing modules enabled the complete use of all of the carbon atoms from oleic acid (released from plant oil) for the green synthesis of structurally diverse bifunctional chemicals.

Upgrading furfuralcohols and furfurals to furancarboxylic acids is of great significance for high value-added downstream chemicals synthesis and biomass conversion. Developing an efficient catalyst is the key to acquiring a completely sustainable process. Herein, nitrogen-doped carbon-supported bimetallic AuPd bowl-like catalysts were synthesized. The surface wettability of nitrogen-doped carbon was well adjusted by the nitrification process. Benefiting from the alloying effect of bimetallic AuPd catalyst and the formation of hydroxyl radical initiated by H 2 O dissociation on the hydrophilic surface of nitrated nitrogen-doped carbon, base-free aerobic oxidation of 5-hydroxymethylfurfural (HMF) could produce the highest 2,5-furandicarboxylic acid (FDCA) yield of 93.9 %. In-situ infrared spectroscopy uncovered adsorption configuration of HMF, and the nitrated carbon surface was favorable for HMF and intermediates to enter the active sites, greatly promoting the catalytic oxidation process. Employing other furfuralcohols (furfuryl alcohol, furan-2,5-diyldimethanol, 2,5-bishydroxymethylfuran) as well as furfural and 5-methylfurfural as starting materials, 35.6-95.4 % yield of furancarboxylic acids (FDCA, 2-furoic acid, 5-methyl-2-furoic acid) were also obtained. Moreover, the developed catalysts could maintain excellent stability and activity after four successive runs. This deep insight into the role of bimetallic synergy and surface wettability provides a basis for the rational design of the highly efficient catalysts for the oxidation of furfuralcohols and furfurals and related reactions., (© 2022 Wiley-VCH GmbH.)

The oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) is highly attractive as FDCA is considered as substitute for the petrochemically derived terephthalic acid. There are only few reports on the direct use of unrefined HMF solutions from biomass resources and the influence of remaining constituents on the catalytic processes. In this work, the oxidation of HMF in a solution as obtained from hydrolysis and dehydration of saccharides in chicory roots was investigated without intermediate purification steps. The amount of base added to the solution was critical to increase the FDCA yield. Catalyst deactivation occurred and was attributed to poisoning by amino acids from the bio-source. A strong influence of amino acids on the catalytic activity was found for all supported Au, Pt, Pd, and Ru catalysts. A supported AuPd(2 : 1)/C alloy catalyst exhibited both superior catalytic activity and higher stability against deactivation by the critical amino acids., (© 2022 The Authors. ChemSusChem published by Wiley-VCH GmbH.)

The electrochemical oxidation of the biomass platform 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA), is an important reaction in the emerging area of renewable energy-powered biomass valorization. A key limitation in this field is the ill-defined nature of the catalytic sites of the highest-performing materials that limits the fundamental insights that can be extracted. To this end, a conductive metal-organic framework-based electrocatalytic model system with well-defined M-O 4 active sites for electrochemical HMF oxidation was developed. These materials were found to be highly active towards FDCA generation, with product yields of over 95 %. In parallel, infrared spectroscopy was employed to capture a surface-bound aldehyde group as the key intermediate in the catalytic cycle, which forms once M(II/III) oxidation occurs. This work illustrates the advantage of utilizing molecularly defined active sites coupled with operando spectroscopy to provide fundamental insights into a variety of electrosynthetic reactions and thus paves the way for future catalyst design., (© 2021 Wiley-VCH GmbH.)

A great deal of attention has been directed toward studying the electrochemical oxidation of 5-hydroxymethylfurfural (HMF), a molecule that can be obtained from biomass-derived cellulose and hemicellulose, to 2,5-furandicarboxylic acid (FDCA), a molecule that can replace the petroleum-derived terephthalic acid in the production of widely used polymers such as polyethylene terephthalate. NiOOH is one of the best and most well studied electrocatalysts for achieving this transformation; however, the mechanism by which it does so is still poorly understood. This study quantitatively examines how two different dehydrogenation mechanisms on NiOOH impact the oxidation of HMF and its oxidation intermediates on the way to FDCA. The first mechanism is a well-established indirect oxidation mechanism featuring chemical hydrogen atom transfer to Ni 3+ sites while the second mechanism is a newly discovered potential-dependent (PD) oxidation mechanism involving electrochemically induced hydride transfer to Ni 4+ sites. The composition of NiOOH was also tuned to shift the potential of the Ni(OH) 2 /NiOOH redox couple and to investigate how this affects the rates of indirect and PD oxidation as well as intermediate accumulation during a constant potential electrolysis. The new insights gained by this study will allow for the rational design of more efficient electrochemical dehydrogenation catalysts., (© 2022 The Authors. ChemSusChem published by Wiley-VCH GmbH.)

Developing an efficient catalyst to upgrade 5-hydroxymethylfurfural (HMF) to high-value-added downstream chemicals is of great significance in biomass conversion. Nanorod (110)-, nanocube (100)-, and nanooctaheron (111)-CeO 2 -supported Au nanoparticles were prepared to investigate the intrinsic effect of CeO 2 crystal faces on the oxidation of HMF to 2,5-furandicarboxylic acid (FDCA). The experimental results and density functional theory calculation revealed that the concentration of oxygen vacancy (V O ) for exposed specific crystal faces was crucial to the oxygen adsorption ability, and Au/nanorod-CeO 2 with the highest V O concentration promoted the formation of more oxygen active species (superoxide radical) on CeO 2 (110) crystal face than (100) and (111) crystal faces. Besides, the higher V O concentration could provide a strong adsorption ability of HMF, greatly boosting the activation of HMF. Thus, these results led to a superior catalytic activity for HMF oxidation over Au/nanorod-CeO 2 (FDCA yield of 96.5 %). In-situ Fourier-transform (FT)IR spectroscopy uncovered the HMF oxidation pathway, and the possible catalytic mechanism was proposed. The deep insight into the role of regulation for crystal faces provides a basis for the rational design of highly active facets for the oxidation of HMF and related reactions., (© 2021 Wiley-VCH GmbH.)

Conversion of biomass into biofuels and high value-added chemicals is a promising strategy to solve the increasingly deteriorating environmental problems caused by fossil energy consumption. The development of efficient technologies and methods is the premise and guarantee to realize the high-value conversion of biomass. 5-Hydroxymethylfurfural (HMF), as a versatile biomass platform compound, is generated via dehydration of hexoses (e. g., fructose and glucose) derived from cellulosic biomass. This Review gives an overview of the advances and challenges of electro- and photocatalytic oxidation of biomass-derived HMF to high-value chemicals such as 2,5-formylfuran (DFF) and 2,5-furandicarboxylic acid (FDCA). These strategies and methods for the preparation of high-value chemicals by electro- and photocatalytic oxidation of HMF, coupled with, for example, hydrogen evolution reaction, organic substrate reduction, CO 2 reduction reaction, or N 2 reduction reaction, were summarized and discussed. Moreover, the catalytic efficiency and mechanism of different types of catalysts were also introduced in these conversion systems., (© 2022 Wiley-VCH GmbH.)

The development of reusable polymeric materials inspires an attempt to combine renewable biomass with upcycling to form a biorenewable closed system. It has been reported that 2,5-furandicarboxylic acid (FDCA) can be recovered for recycling when incorporated as monomers into photodegradable polymeric systems. Here, we conduct density functional theory (DFT) studies with periodic boundary conditions on microscopic structures involved in the photodegradation of polymeric chains incorporating FDCA and 2-nitro-1,3-benzenedimethanol. The photodegradation process of polymeric chains is studied using time-dependent excited-state molecular dynamics (TDESMD) in vacuum and aqueous environments. Changes in the photophysical properties for reaction intermediates are characterized by ground-state observables. The distribution of reaction intermediates and products is obtained from TDESMD trajectories using cheminformatics techniques. Results show that a higher degree of polymeric chain degradation is achieved in the vacuum environment. Additionally, one finds that the FDCA molecule is recoverable in the aqueous environment, in qualitative agreement with experimental findings.

Reactions of N'N' -bis(3-pyridylmethyl)oxalamide ( L 1 ), N'N' -bis(4-pyridylmethyl)oxalamide ( L 2 ), or N,N' -bis(3-pyridylmethyl)adipoamide) ( L 3 ) with angular dicarboxylic acids and Ni(II) salts under hydro(solvo)thermal conditions afforded a series of coordination polymers: {[Ni( L 1 )(OBA)(H 2 O)]·H 2 O} n (H 2 OBA = 4,4-oxydibenzoic acid), 1 , {[Ni( L 1 )(SDA)(H 2 O) 2 ]·H 2 O·CH 3 OH} n (H 2 SDA = 4,4-sulfonyldibenzoic acid), 2 , {[Ni( L 2 )(OBA)]·C 2 H 5 OH} n , 3 , {[Ni( L 2 )(OBA)]·CH 3 OH} n , 4 , {[Ni 2 ( L 2 )(SDA) 2 (H 2 O) 3 ]·5H 2 O} n , 5 , {[Ni 2 ( L 2 )(SDA) 2 (H 2 O) 3 ]·H 2 O·2C 2 H 5 OH} n , 6 , {[Ni( L 3 )(OBA)(H 2 O) 2 ]·2H 2 O} n , 7 , {[Ni( L 3 )(SDA)(H 2 O) 2 ]·2H 2 O} n , 8 , and {[Ni( L 3 ) 0 . 5 (SDA)(H 2 O) 2 ]·0.5C 2 H 5 OH} n , 9 , which have been structurally characterized by using single-crystal X-ray crystallography. Complex 1 exhibits an interdigitated 2D layer with the 2,4L2 topology and 2 is a 2D layer with the sql topology, while 3 and 4 are 3D frameworks resulting from polycatenated 2D nets with the sql topology and 5 and 6 are 2-fold interpenetrated 3D frameworks with the dia topology. Complexes 7 and 8 are 1D looped chains and 9 is a 2D layer with the 3,4L13 topology. The various structural types in 1 - 9 indicate that the structural diversity is subject to the flexibility and donor atom position of the neutral spacer ligands and the identity of the angular dicarboxylate ligands, while the role of the solvent is uncertain. The iodine adsorption of 1 - 9 was also investigated, demonstrating that that the flexibility of the spacer L 1 - L 3 ligands can be an important factor that governs the feasibility of the iodine adsorption. Moreover, complex 9 shows a better iodine adsorption and encapsulates 166.55 mg g -1 iodine in the vapor phase at 60 °C, which corresponded to 0.38 molecules of iodine per formula unit.

In this study, hydrogels containing azelaic acid were developed using chitosan or HPMC (1-7%) for local treatment of acne vulgaris. Physicochemical properties such as viscosity, pH and mechanical properties were evaluated. In vitro release and ex vivo permeability studies were performed using the Franz diffusion cell system. The pH of the hydrogels was highly compatible with the skin pH and varied between 4.38 and 5.84. The cumulative release percentages of the hydrogels at the end of 6 hours were 65-78%, whereas the marketed product yielded 50% drug release. According to the ex vivo permeability results, azelaic acid accumulated in the skin was found to be 9.38 ± 0.65% (marketed cream), 19.53 ± 1.06% (K3), 10.96 ± 1.91% (H6). The antiacne studies with Cutibacterium acnes revealed that K3 (29.45 ± 0.95) and H6 (32.35 ± 0.15) had higher inhibition zones compared to the marketed cream (24.50 ± 0.90). Additionally, the gels were found to be highly stable as a result of the stability studies for 6 months. Among the hydrogels that were prepared based on experimental findings, K3 (3% Chitosan) and H6 (6% HPMC) represented elevated in vitro release profile, higher permeability and increased antiacne activity. The findings of this research suggest that the developed hydrogels might be an alternative to the marketed product.

Phthalates and other plasticizers are detected in high amounts in the indoor environment and therefore house dust can be an exposure source. Especially children have a relatively high unintended uptake of house dust, thus a higher exposure to plasticizers compared to adults may be possible. As accurate as possible exposure assessment data of the oral bioavailability of these compounds are necessary, however only one in vivo study with piglets is available so far. The aim of this study was to examine the oral bioavailability of phthalates and DINCH® in humans, which occur in typical house dust samples. We focused on the high molecular weight phthalates DEHP and DINP and their substitute DINCH®. Eleven volunteers ingested 6 g of house dust sieved to 2 mm. The urine was collected over a period of 36 h. The excreted plasticizers metabolites were quantified by an LC-MS/MS method. The mean recovery of urine metabolites was 51 % ± 20 % for DEHP, 26 % ± 13 % for DINP and 19 % ± 6% for DINCH® based on the parent compounds administered as dust samples. The metabolites of DEHP, DINP and DINCH® reached their maximum concentration after 2-19 hours post dose in urine. The bioavailability of DEHP was in agreement among the different dust samples. For DEHP, we were able to confirm previous findings from the oral bioavailability study with piglets and we could not observe a significant difference between the dust particle size (65 μm vs 2 mm) and the bioavailability. Considering the observed bioavailability, an estimated dust intake of 50 mg/d for toddlers can substantially contribute to the total plasticizer exposure., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests, (Copyright © 2021. Published by Elsevier B.V.)

A highly enantioselective O-propargylation catalyzed by combining a phosphine-nickel complex and an axially chiral sodium dicarboxylate has been developed. The transformation features mild reaction conditions, a broad substrate scope, and excellent functional group tolerance, offering an efficient approach to an array of enantioenriched O -propargyl hydroxylamines. Mechanistic studies support the presumed role of the chiral carboxylate as a counterion for nickel catalysis enabling the discovery of highly stereoselective transformations. The power of this reaction is illustrated by its application in the asymmetric total synthesis of potent firefly luciferase inhibitors and ( S )-dihydroyashabushiketol.

The search for new methods of antiviral therapy is primarily focused on the use of substances of natural origin. In this context, a triterpene compound, betulin 1, proved to be a good starting point for derivatization. Thirty-eight betulin acid ester derivatives were synthetized, characterized, and tested against DNA and RNA viruses. Several compounds exhibited 4- to 11-fold better activity against Enterovirus E (compound 5 EC 50 : 10.3 μM) and 3- to 6-fold better activity against Human alphaherpesvirus 1 (HHV-1; compound 3c EC 50 : 17.2 μM). Time-of-addition experiments showed that most of the active compounds acted in the later steps of the virus replication cycle (e.g., nucleic acid/protein synthesis). Further in-silico analysis confirmed in-vitro data and demonstrated that interactions between HHV-1 DNA polymerase and the most active compound, 3c, were more stable than interactions with the parent non-active betulin 1., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

In this study, the modulation of amounts sulfathiazolium cations in different 2,6-pyridinedicarboxylates is demonstrated. An uncommon monoionic sulfathiazolium zinc 2,6-pyridinedicarboxylate (1:1 electrolyte) complex was characterized. Conventional sulfathiazolium zinc-bis-2,6-pyridinedicarboxylate dianionic complexes (2:1 electrolyte) were formed when hydroxyaromatic compounds such as 1,3-dihydroxybenzene or 3-nitrophenol were used as guest components. Thus, with the aid of the hydroxyaromatic molecules the zinc-bis-2,6-pyridinedicarboxylate complexes were stabilized with the relatively large sized sulfathiazolium cations. It was a consequence of domain expansion by the phenolic compounds. Sandwiched aromatic guests between the 2,6-pyridinedicarboxylates provided appropriate packing to accommodate the two large cations in the self-assemblies, which helped to modulate the amounts of sulfathiazole in different formulations. Antibacterial activities with E. coli DH5α have shown that the salt and the complexes have lower g/ml antibacterial activity than the parent drug., (© 2021 Wiley Periodicals LLC.)

Near-infrared (NIR)-light-triggered photothermal therapy (PTT) is usually associated with undesirable damage to healthy organs nearby due to the high temperatures (>50 °C) available for tumor ablation. Low-temperature PTT would therefore have tremendous value for clinical application. Here, we construct a hypoxia-responsive gold nanorods (AuNRs)-based nanocomposite of CRISPR-Cas9 for mild-photothermal therapy via tumor-targeted gene editing. AuNRs are modified with azobenzene-4,4'-dicarboxylic acid (p-AZO) to achieve on-demand release of CRISPR-Cas9 using hypoxia-responsive azo bonds. In the hypoxic tumor microenvironment, the azo groups of the hypoxia-activated CRISPR-Cas9 nanosystem based on gold nanorods (APACPs) are selectively reduced by the overexpression of reductases, leading to the release of Cas9 and subsequent gene editing. Owing to the knockout of HSP90α for reducing the thermal resistance of cancer cells, highly effective tumor ablation both in vitro and in vivo was achieved with APACPs under mild PTT., (© 2021 Wiley-VCH GmbH.)

Carboxylated cellulose nanocrystals (CNCs) were produced from cotton linter using a mixture of a dicarboxylic acid (maleic acid or succinic acid) and its corresponding anhydride with or without catalyst in acetic acid as solvent. The low solubilities of these dicarboxylic acids can ease chemical recovery and decrease environmental impact (especailly maleic acid is a U.S. FDA approved indirect food additive (21CFR175-177)) and capital costs compared with the conventional concentrated sulfuric acid hydrolysis for producing CNCs. The dicarboxylic-acid-produced CNCs (DC-CNCs) contained surface carboxyl groups of approximately 0.5 mmol/g, with ranges of dimensions of 50-150 nm in diameter and 50-700 nm in length. Birefringence was observed in the DC-CNC suspensions above critical concentrations. However, fingerprint texture was only observed in the DC-CNC suspensions produced with catalyst p-toluenesulfonic acid. Scanning electron microscopy images of the cross section of DC-CNC films revealed a periodic ordered multilayer structure. DC-CNCs were also produced using recycled dicarboxylic acids., (Published by Elsevier Ltd.)

A novel 3-D biopolymer-based adsorption-photocatalytic composite, polyaniline/dicarboxyl acid cellulose@graphene oxide was synthesized and was employed to remove the reactive brilliant red K-2G from aqueous solution. The addition of dicarboxyl acid cellulose could improve the morphology, structure, stability and dispersity of the nanocomposite, thus providing excellent adsorption and photocatalysis performance to the product. Batch of experiments were conducted in two scenarios: adsorption followed by photocatalysis process and simultaneous adsorption-photocatalysis process. For the first scenario, adsorption equilibrium can be reached within 25 min, the expected adsorption capacity was 447.0 mg·g -1 ; the subsequent photocatalysis process was carried out under light irradiation and the removal capacity could further improve to 729.0 mg·g -1 under equilibrium state (about 180 min). For the simultaneous adsorption-photocatalytic process, the removal capacity was about 558.1 mg·g -1 at about 25 min and the total removal capacity could reach to 733.3 mg·g -1 under equilibrium state. PANI-DCC@GO exhibited excellent reusability and had potential in the treatment of dyes polluted wastewater., (Copyright © 2021 Elsevier B.V. All rights reserved.)

In an effort to probe the biophysical mechanisms of inhibition for ten previously-reported inhibitors of metallo-β-lactamases (MBL) with MBL IMP-1, equilibrium dialysis, metal analyses coupled with atomic absorption spectroscopy (AAS), native state mass spectrometry (native MS), and ultraviolet-visible spectrophotometry (UV-VIS) were used. 6-(1H-tetrazol-5-yl) picolinic acid (1T5PA), ANT431, D/l-captopril, thiorphan, and tiopronin were shown to form IMP-1/Zn(II)/inhibitor ternary complexes, while dipicolinic acid (DPA) and 4-(3-aminophenyl)pyridine-2,6-dicarboxylic acid (3AP-DPA) stripped some metal from the active site of IMP but also formed ternary complexes. DPA and 3AP-DPA stripped less metal from IMP-1 than from VIM-2 but stripped more metal from IMP-1 than from NDM-1. In contrast to a previous report, pterostilbene does not appear to bind to IMP-1 under our conditions. These results, along with previous studies, demonstrate similar mechanisms of inhibition toward different MBLs for different MBL inhibitors., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The synthesis of hydrazides formed by quinazolin-4(3H)-ylidenehydrazine and dicarboxylic acids, as well as their further modification are described in the present manuscript. It was shown that above-mentioned hydrazides may be obtained via acylation of initial quinazolin-4(3H)-ylidenehydrazine by corresponding acylhalides, cyclic anhydrides and imidazolides of dicarboxylic acids monoesters. Obtained hydrazides were converted into [1,2,4]triazolo[1,5-c]quinazolines that were used as initial compounds for chemical modification aimed to the introduction of amide fragment to the molecule. The IR, 1H NMR and chromato-mass spectral data of obtained compounds were studied and discussed. Obtained substances were studied for anti-inflammatory activity using carrageenan-induced paw inflammation model. Amides of ([1,2,4]triazolo[1,5-c]quinazoline-2-yl)alkyl carboxylic acids were detected as promising class of anti-inflammatory agents for further purposeful synthesis and profound study of anti-inflammatory activity.

The TET (Ten-Eleven Translocation) dioxygenase enzyme family comprising 3 members, TET1-3, play key roles in DNA demethylation. These processes regulate transcription programs that determine cell lineage, survival, proliferation, and differentiation. The impetus for our investigations described here is derived from the need to develop illuminating small molecule probes for TET enzymes with cellular activity and specificity. The studies were done so in the context of the importance of TET2 in the hematopoietic system and the preponderance of loss of function somatic TET2 mutations in myeloid diseases. We have identified that 2-hydroxy-4-methylene-pentanedicarboxylic acid 2a reversibly competes with the co-substrate α-KG in the TET2 catalytic domain and inhibits the dioxygenase activity with an IC 50  = 11.0 ± 0.9 μM at 10 μM α-KG in a cell free system and binds in the TET2 catalytic domain with K d  = 0.3 ± 0.12 μM., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The main aim of the present study is to synthesize a hitherto unreported polymer of chitosan (CS) and 2,5-furandicarboxylic acid (FDCA) derived from renewable biomass resources. For this purpose, CS was chosen which had -NH 2 groups as abundant active sites. Synthesis of 2,5-furandicarboxylic acid-enriched-chitosan polymer (CS-FDCA) was carried out by reaction involving EDC-NHS coupling reagents. The structure of CS-FDCA polymer was confirmed by various characterization techniques such as Fourier-transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance ( 1 H NMR), X-ray powder diffraction (XRD), high resolution-field emission scanning electron microscope (HR-FESEM), and thermogravimetric analysis (TGA). Moreover, CS and CS-FDCA were scrutinized to examine their efficacies towards ameliorate inflammation via detection of lipopolysaccharide (LPS) induced nitric oxide (NO) production. As compared to CS, CS-FDCA with low concentration (1.0 μM) exhibited the better efficacy to reduce the NO production. Furthermore, CS-FDCA polymer showed high as 12.6% of Cu 2+ ion uptake while CS showed 9.2% of Cu 2+ ion uptake. Overall, it can be inferred that CS-FDCA polymer is expected to be used for biomedical application and for the removal of metal contaminants from industrial wastewater., Competing Interests: Declaration of competing interest The author declares that there is no competitive or financial interest known to influence the work reported in this paper., (Copyright © 2021. Published by Elsevier B.V.)

Photodecarboxylase from Chlorella variabillis (CvFAP) is one of the three known light-activated enzymes that catalyzes the decarboxylation of fatty acids into the corresponding C1-shortened alkanes. Although the substrate scope of CvFAP has been altered by protein engineering and decoy molecules, it is still limited to mono-fatty acids. Our studies demonstrate for the first time that long chain dicarboxylic acids can be converted by CvFAP. Notably, the conversion of dicarboxylic acids to alkanes still represents a chemically very challenging reaction. Herein, the light-driven enzymatic decarboxylation of dicarboxylic acids to the corresponding (C2-shortened) alkanes using CvFAP is described. A series of dicarboxylic acids is decarboxylated into alkanes in good yields by means of this approach, even for the preparative scales. Reaction pathway studies show that mono-fatty acids are formed as the intermediate products before the final release of C2-shortened alkanes. In addition, the thermostability, storage stability, and recyclability of CvFAP for decarboxylation of dicarboxylic acids are well evaluated. These results represent an advancement over the current state-of-the-art., (© 2021 The Authors. Published by Wiley-VCH GmbH.)

In this study, various structurally similar aliphatic dicarboxylic acids, namely, succinic acid, glutaric acid, adipic acid, and pimelic acid, were employed as coformers to obtain phase pure cocrystals with berberine chloride (BCl) by a slow solvent evaporation method. The structures of the four novel salt-cocrystals of BCl were determined by single crystal X-ray diffraction analysis and their solid-state properties were characterized. Compared with BCl·2H 2 O, all the cocrystals showed a higher melting point, improved powder dissolution and intrinsic dissolution rate (IDR), and lower hygroscopicity. It is noteworthy that the melting points and IDRs of these cocrystals exhibit an odd-even alternation with the carbon chain length of the acids.

The focus of present work was to prepare salt of aripiprazole (APZ) with dicarboxylic acids to improve physicochemical properties the drug. Dicarboxylic acids used in the study were malonic acid, maleic acid and succinic acid. The salts were prepared with solubilization-crystallization method. The salts were characterized for pH-solubility, dissolution, and stabilities. The Fourier infrared spectroscopy, X-ray powder diffraction, differential scanning calorimetry and near infrared chemical imaging indicated formation of new solid phase. pH-solubility profiles of the salts were similar to the drug except higher solubility were observed in the salts at all tested pH. The highest solubility was observed for APZ-Malonate salt among all the prepared salts. The solubility curve was inverted 'V' shape for APZ-maleate and APZ-succinate while it was inverted 'U' shape for APZ-malonate. The water solubility of APZ, APZ-malonate, APZ-maleate and APZ-succinate were 0.07 ± 0.02, 3503.9 ± 37.4, 269.3 ± 6.9 and 729.4 ± 9.4 µg/mL, respectively. The dissolution was 2.9 ± 0.4, 18.4 ± 3.9, 19.5 ± 1.4 and 36.6 ± 4.0% in 45 min for APZ, APZ-maleate, APZ-malonate, and APZ-succinate. The stabilities of the salts were similar to the drug. Thus, salts improved the physicochemical properties of the drug, and have similar stability profiles as that of APZ.

A silica based hydrophilic stationary phase bonding with 2,3-pyrazinedicarboxylic anhydride and amino groups was synthesized via amino-acid anhydride ring opening reaction. The bonded groups could not only provide hydrophilic interaction, but also electrostatic, π-π and hydrogen bonding interactions, etc. The results of characterization with elemental analysis and solid-state 13 C cross-polarization magic-angle-spinning NMR indicated the successful preparation of amino and carboxyl bonded stationary phase named ZAC. The ζ-potential of ZAC stationary phase showed the negatively charge was dominate at pH larger than 3.5. Chromatographic evaluation revealed that ZAC stationary phase behaved well under HILIC mode. It showed different selectivity and retention compared to some typical commercial columns, and it was validated by the separation of chitooligosaccharides, flavonoid glycosides, organic acids and alkaloid samples. Based on the different selectivity between ZAC stationary phase and C18 columns, ZAC stationary phase also showed different selectivity with C18. And it was verified by the separation of Lonicerae Japonicae Flos and Menispermi Rhizoma extracts., Competing Interests: Declaration of Competing Interest The authors have declared no conflict of interest., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Carboxylation of bis(pyrazol-1-yl)alkanes by oxalyl chloride was studied. It was found that 4,4'-dicarboxylic derivatives of substrates with electron-donating methyl groups and short linkers (from one to three methylene groups) can be prepared using this method. Longer linkers lead to significantly lower product yields, which is probably due to instability of the intermediate acid chlorides that are initially formed in the reaction with oxalyl chloride. Thus, bis(pyrazol-1-yl)methane gave only monocarboxylic derivative even with a large excess of oxalyl chloride and prolonged reaction duration. An alternative approach involves the reaction of ethyl 4-pyrazolecarboxylates with dibromoalkanes in a superbasic medium (potassium hydroxide-dimethyl sulfoxide) and is suitable for the preparation of bis(4-carboxypyrazol-1-yl)alkanes with both short and long linkers independent of substitution in positions 3 and 5 of pyrazole rings. The obtained dicarboxylic acids are interesting as potential building blocks for metal-organic frameworks.

Conjugation, that is, covalent linkage, to immunological proteins is a common strategy to address the low immunogenicity issue of carbohydrate antigens in vaccine development. This chapter describes an easy and efficient method for oligosaccharide-protein conjugation employing dicarboxylic acid linkers. In this regard, a free amino group is introduced to an oligosaccharide antigen to facilitate coupling with the bifunctional linker upon reaction with its corresponding disuccinimidyl ester. The resultant monosuccinimidyl ester of the oligosaccharide antigen then reacts with the free amino groups of a carrier protein to provide the desired oligosaccharide-protein conjugate.