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A 1:1 cocrystal of 4-oxo-4-(pyridin-2-ylamino)butanoic acid (APS) and benzoic acid (BA), APS-BA (1:1), was prepared and characterized by Differential Scanning Calorimetry (DSC) and Thermo Gravimetric Analysis (TGA), Infrared (FT-IR), powder X-ray diffraction (PXRD) and single crystal X-ray diffraction (SCXRD) studies. Crystal structure reveals that APS-BA (1:1) is formed by joint N-H…O and O-H…N hydrogen bonding between APS and BA molecule resulting in a hetero-dimeric R²₂(8) motif. A pair of C-H…O interactions and another pair of O-H…O hydrogen bonds between APS molecules ensures formation of a one-dimensional zig-zag hydrogen bonded tape of APS molecules, with the BA molecules occupying pendant position. Hirshfeld surface analysis including energy framework and lattice energy calculations were performed and compared with those of the components APS and BA. Comparison of the computed energetics of individual interactions and the lattice energies showed that cocrystal formation is thermodynamically favoured.

Thiazolidin-4-one sixteen analogues (1–16) were synthesized, characterized and tested against urease inhibitory potential. All synthesized analogues showed varied degrees of IC₅₀ values from excellent to good potency as compared to standard thiourea. Analogues 8, 7 and 5 were the most potent analogue with IC₅₀ values 1.10 ± 0.20, 2.30 ± 0.30 and 4.50 ± 0.10 µM respectively among the series. These analogues showed many folds better potency as compared to standard thiourea. All other analogues also showed excellent potency which was many folds better than standard thiourea. Structure-activity relationship was established and binding interactions of the most potent analogues were confirmed through molecular docking studies.

Kinetics of isosorbide (S) oxidation by Ce(IV) in aqueous HClO₄ medium has been examined via spectrophotometric technique at fixed ionic strength and temperature. The reaction showed a 1: 2 stoichiometry (S: Ce(IV)). The reaction was studied under pseudo-first order conditions. The dependency of the rate of oxidation reaction on the reactants’ concentrations showed that the reaction was first order in [Ce(IV)], whereas in both [H⁺] and [S], its order was lower than unity. The oxidation rate was directly proportional to ionic strength as well as dielectric constant of the reaction medium. However, it should be mentioned that adding Ce(III) had remarkably not affect the rate. The isosorbide oxidation product was recognized as (1S,4S,5R)-4-hydroxy-2,6-dioxabicyclo[3.3.0]octan-8-one). A mechanistic scheme for oxidation coherent with the observed kinetics was proposed. The rate-law expression was derived which was agreed with the acquired outcomes. The calculated activation quantities recommended construction of a rigid intermediate through the reaction and such process was endothermic and non-spontaneous.

The titled salt was synthesized by adding 2-Amino-4-methyl pyridine and Oxalic acid at 1:1 ratio, crystallizes in P2₁/n space group. The crystal structure of the salt 2-amino-4-methylpyridinium oxalate has been determined from the single crystal X-ray analysis. The crystal structure reveals that a protonation process took place in the solid; this confirms the compound is a salt. The molecular structure of the salt forms hydrogen bonding interactions in the crystal. The crystal structure is stabilized by N–H···O and C–H···O type of interactions. The Hirshfeld surface and 2D fingerprint plot analysis has been performed to understand the weak and strong interactions of the salt molecule. The nitrogen atoms N1 and N2 of 2A4MP are hydrogen bonded with a carboxyl group of oxalate forms a $R_2^2$(8) ring motif via intermolecular interactions N1–H1A···O1, N2–H2B···O2. The QTAIM analysis of electron density at the critical points of intermolecular interactions shows the charge density distribution of weak and strong interactions. The in-silico ADME predicts that the salt exhibits the drug-likeness property, high bioavailability and high gastrointestinal absorption.

The following study explores the potential use of Marrubium vulgare L. essential oil as a plant-based anticorrosion agent against copper in 0.5 M H₂SO₄. Through electrochemical experiments, the oil significantly reduces copper deterioration in this sulfurous atmosphere. Based on of potentiodynamic polarization curves, Marrubium vulgare L. has a 95.51 % efficiency in preventing corrosion at a concentration of 1 g/l oil. An appropriate electrical circuit model is employed to calculate electrochemical impedance characteristics. The Surface investigation (SEM/EDX) identifies a protective layer on the copper substrate, significantly blocking active copper corrosion sites.

The surface components of mild steel used in field applications are always subject to wear and corrosion attacks. Epoxy coatings serve to improve the surface properties of mild steel; nonetheless, they do not deliver a multiplexed advantage compared to their coating with inert non-metallic particles. The parametric addition of maize cob ash nanoparticles modified with 0.5 wt% silver nanoparticles in the epoxy coating of mild steel was investigated. The coating was done using the spraying method. The transmission and scanning electron microscope, X-ray diffraction and electrochemical test in mixed acid environment were used in the characterization of the developed composites coating. A 42.86 and 96.16 % improvement in hardness values and corrosion resistance of mild steel was obtained at modified 8 wt% maize cob ash nanoparticles/epoxy coating. The corrosion potential of the coated samples tends to be higher, whereas that of the uncoated mild steel is lower. This study demonstrates that epoxy-8 wt% maize cob ash nanoparticles modified with 0.5 wt% silver nanoparticles can be used to enhance the anti-corrosion of mild steel in a mixed acid environment.

The present study demonstrates the green selective microdetermination of Cd²⁺employing a newly established polymer inclusion membrane (PIM) in an environmental process. The PIM is made up of 40 % di(2-ethylhexyl) phosphoric acid (D2EHPA), 9 % dioctyl sebacate (DOS), and 50 % polyvinyl chloride (PVC). 2-Amino-4-(3-chlorophenylazo) pyridine-3-ol (ACPAP) is the colorimetric reagent utilized to determine Cd²⁺ concentration. Cd²⁺ is elicited into the PIM in this system as the cadmium-D2EHPA complex, which then reacts with ACPAP. ACPAP yields a violet Cd²⁺−ACPAP complex. The λ_max for the PIM based optode was 657 nm. The variables pH, quantity of reagent, quantity of additive, and duration of response, which substantially influence the response of the proposed optode, were optimized using design of experiment (DOE) statistical method. At ideal conditions, the optode membrane's reproducibility, high stability, and relatively extended lifetime indicate its potential for accurate and precise monitoring of Cd²⁺ ion concentration. Under ideal conditions, the optode has a detection limit of 1.60 ng mL⁻¹ and a measurement (quantification) limit of 5.0 ng mL⁻¹. The PIM-ACPAP system was utilized effectively to detect Cd²⁺ ions in environmental real samples.

This study aimed to identify chemical components and evaluate the antioxidant and antibacterial activities of ethanolic and dichloromethane extracts of Ammi visnaga (L.). Both extracts contained flavonoids, coumarins, and glycosides, with the ethanolic extract also exhibiting tannins and reducing sugars. Qualitative HPLC/UV-ESI-MS analysis revealed abundant polyphenols, particularly flavonoids and furanochromones, such as rhamnazin, kaempferol, rhamnetin, khellin, visnagin, khellinin, and khellol. Antimicrobial activity against Gram-positive and Gram-negative bacteria was assessed, with Klebsiella pneumoniae showing sensitivity to the ethanol extract, resulting in a 9 mm inhibition zone. The dichloromethane extract exhibited a 9 mm inhibition zone against Acinetobacter baumannii, with a minimum inhibitory concentration (MIC) of 10 µL/mL for both extracts and all susceptible strains. Antioxidant activity, measured by radical DPPH∙ radical reduction test revealed significant reducing power in the ethanolic extract, with an IC50 = 1.383 ± 0.069 mg/mL, compared to IC50 = 0.095 ± 0.009 mg/mL for ascorbic acid, used as reference.

Errors are found in several of the published volumetric properties in the paper by Babu and coworkers. The authors’ calculated partial molar volumes and calculated partial molar excess volumes of the individual mixture components are not consistent with the published excess molar volumes reported in the paper.

In this work, we report the synthesis of a series of new derivatives of 1,3,5-oxadiazine - (Z)-N,3-dicyclohexyl-6-R-4-(trichloromethyl)-3,4-dihydro-2H-1,3,5-oxadiazin-2-imines. The method for preparing these compounds was based on the [4 + 2] cycloaddition reaction of dicyclohexylcarbodiimide to N-(2,2,2-trichloroethylidene)carboxamides formed in situ. Target products were obtained in 74–87 % yield. The structure of the obtained derivatives of 2H-1,3,5-oxadiazin-2-imines was confirmed by IR, ¹H, and ¹³C NMR spectroscopy, as well as the results of selective X-ray diffraction analysis.