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In the present study crystalline unsymmetrical diarylidene ketone derivatives BNTP and BDBC have been prepared by two sequential acid catalyzed aldol condensation reactions in a one pot manner.

Herein, a one-pot synthesis of tetra-substituted imidazole, 4-chloro-2-(1-(4-methoxyphenyl)-4,5-diphenyl-1H-imidazol-2-yl)phenol (HL), is reported by the reaction of benzil, 5-chlorosalicylaldehyde, ammonium acetate and anisidine.

Carbon nitride-based 2D materials, such as C3N3 and C3N5, and their role as an interlayer in perovskite solar cells to stabilize NiOx hole selectivity are investigated.

Cement needs to be designed to prevent short-term and long-term gas migration scenarios. In the short term, the cement must prevent gas flow immediately following cement placement. In the long term, the cement must resist pressure and temperature cycling during drilling and production. Wells are subjected to substantial stresses from pressure and well testing, injection and stimulation treatments, thermal effects, production cycling, and changes in the surrounding formation over years. Due to these stresses, the cement sheath damage can occur during drilling, perforation and stimulation, and subsequent production. Polymer latex has been used to help reduce the fluid loss to minimize gas migration and aid in the mixing ability of cement slurries. However, there are some engineers who believe that polymer latex will improve cement mechanical properties.The objective of this study is to evaluate the effect of polymer latex on cement mechanical properties after curing at elevated temperature and pressures. Experimental work in this study includes formulations at different polymer latex concentrations, densities measurements, rheology measurement, fluid loss testing, thickening time tests, curing for 30 days at elevated temperature and pressure, and finally mechanical properties measurements (Young's modulus, Poisson's ratio and compressive strength). The study shows that polymer latex will improve mechanical properties of cementing which will lead to improved wellbore integrity.

The asymmetric unit of the title compound, [Tm2(C7H6NO2)6(H2O)4]·2H2O, contains three 4-aminobenzoate (4ABA) ligands, two coordinated water molecules, a thulium metal ion, and a water molecule of crystallization. The overall structure of the complex (4ABA-Tm) is in the form of a dimer. In the dinuclear thulium complex, symmetry-relevant TmO8 coordination polyhedra are formed by the O atoms of two chelating 4-aminobenzoate ligands, the O atoms of two non-chelating 4-aminobenzoate ligands, and two water molecules. The Tm—O bond lengths range from 2.216 (3) to 2.471 (3) Å with the Tm...Tm separation in the dinuclear complex being 4.7863 (5) Å. The crystal structure features O—H...N, N—H...O, and O—H...O hydrogen-bonding interactions. Further stabilization of the crystal packing is due to C—H...π and off-set π–π stacking interactions. Hirshfeld surface analysis indicates that H...H contacts are the most significant contributors to the crystal packing (45.9%). In addition, a void analysis was performed to check the strength of the crystal packing.

Two imine compounds named as (

Drug resistance developed in microorganisms is a major concern which needs immediate attention from the scientific community.

Ternary oxides NaMO2 (M = Cr, Fe, Co, Al) were prepared by microfluidic processing in water-in-oil emulsions followed by a short annealing step.

Synthetic supramolecular structures constructed through the cooperative action of numerous non-covalent forces are highly desirable as models to unravel and understand the complexity of systems created in nature via self-assembly. Taking advantage of the low cost of 2,4,6-trichloro-1,3,5-triazine (cyanuric chloride) and the sequential nucleophilic substitution reactions with almost all types of nucleophiles, a series of six structurally related novel s-triazine derivatives 1–6 were synthesized and structurally characterized based on their physical, spectral and crystallographic data. The solid-state structures of all the six compounds showed intriguing and unique molecular duplexes featuring NH···N, CH···O and CH···π interactions. Careful analysis of different geometric parameters of the involved H-bonds indicates that they are linear, significant and are therefore responsible for guiding the three-dimensional structure of these compounds in the solid state. The prevalence of sextuple hydrogen bond array-driven molecular duplexes and the possibility of structural modifications on the s-triazine ring render these novel triazine derivatives 1–6 attractive as a platform to create heteroduplex constructs and their subsequent utility in the field of supramolecular chemistry and crystal engineering.

Three symmetrical bis-aryl

NaCrO

Ethyl 4-(4-fluorophenylamino)-2,6-bis(4-(trifluoromethyl)phenyl)-1-(4-fluoro-phenyl)-1,2,5,6-tetrahydropyridine-3-carboxylate (

1,3,4-Oxadiazole moiety is a crucial pharmacophore in many biologically active compounds. In a typical synthesis, probenecid was subjected to a sequence of reactions to obtain a 1,3,4-oxadiazole–phthalimide hybrid (PESMP) in high yields. The NMR (1H and 13C) spectroscopic analysis initially confirmed the structure of PESMP. Further spectral aspects were validated based on a single-crystal XRD analysis. Experimental findings were confirmed afterwards by executing a Hirshfeld surface (HS) analysis and quantum mechanical computations. The HS analysis showed the role of the π⋯π stacking interactions in PESMP. PESMP was found to have a high stability and lower reactivity in terms of global reactivity parameters. α-Amylase inhibition studies revealed that the PESMP was a good inhibitor of α-amylase with an s value of 10.60 ± 0.16 μg/mL compared with that of standard acarbose (IC50 = 8.80 ± 0.21 μg/mL). Molecular docking was also utilized to reveal the binding pose and features of PESMP against the α-amylase enzyme. Via docking computations, the high potency of PESMP and acarbose towards the α-amylase enzyme was unveiled and confirmed by docking scores of −7.4 and −9.4 kcal/mol, respectively. These findings shine a new light on the potential of PESMP compounds as α-amylase inhibitors.

We are exploiting the use of a versatile catalyst taken from heterogeneous catalysis, i.e., ZrOCl2.8H2O to efficiently catalyze the reaction of dextran-succinate conjugate (Dex-SAn) with salicylic acid (SA) under homogeneous reaction conditions. Dextran was first linked with succinic anhydride using triethylamine as a base in DMAc to provide active functionalities (succinate moieties) situated away from the polymer chains. The resultant Dex-SAn conjugate was further esterified with SA using zirconium (IV) oxychloride octahydrate (ZrOCl2.8H2O) as a catalyst at 80 °C under N2. Reaction conditions and amount of catalyst ZrOCl2.8H2O and chiral support MCM-41 were optimized. This reaction methodology resulted in macromolecular prodrugs of SA as Dex-SAn-SA conjugates in good yield. The structures of Dex-SAn and newly synthesized Dex-SAn-SA conjugates were characterized using various spectroscopic techniques, i.e., FT-IR, 1H, and APT-13C NMR spectroscopy. The degree of substitution of SA on to Dex-SAn-SA was determined by UV/Vis spectroscopic methods. This reaction methodology can be modeled as a new protocol for facile attachment of several drug molecules onto the highly potential and biodegradable drug carrier dextran.

Thermal decomposition is a promising route for the synthesis of metal oxide nanoparticles because size and morphology can be tuned by minute control of the reaction variables. We synthesized CoO nanooctahedra with diameters of ∼48 nm and a narrow size distribution. Full control over nanoparticle size and morphology could be obtained by controlling the reaction time, surfactant ratio, and reactant concentrations. We show that the particle size does not increase monotonically with time or surfactant concentration but passes through minima or maxima. We unravel the critical role of the surfactants in nucleation and growth and rationalize the observed experimental trends in accordance with simulation experiments. The as-synthesized CoO nanooctahedra exhibit superior electrocatalytic activity with long-term stability during oxygen evolution. The morphology of the CoO particles controls the electrocatalytic reaction through the distinct surface sites involved in the oxygen evolution reaction.

The formation of a C-C bond through Mizoroki-Heck cross-coupling reactions in water with efficient heterogeneous catalysts is a challenging task. In this current study, a highly reduced graphene oxide (HRG) immobilized palladium (Pd) nanoparticle based catalyst (HRG-Py-Pd) is used to catalyze Mizoroki-Heck cross-coupling reactions in water. During the preparation of the catalyst, amino pyrene is used as a smart functionalizing ligand, which offered chemically specific binding sites for the effective and homogeneous nucleation of Pd NPs on the surface of HRG, which significantly enhanced the physical stability and dispersibility of the resulting catalyst in an aqueous medium. Microscopic analysis of the catalyst revealed a uniform distribution of ultrafine Pd NPs on a solid support. The catalytic properties of HRG-Py-Pd are tested towards the Mizoroki-Heck cross-coupling reactions of various aryl halides with acrylic acid in an aqueous medium. Furthermore, the catalytic efficacy of HRG-Py-Pd is also compared with its non-functionalized counterparts such as HRG-Pd and pristine Pd NPs (Pd-NPs). Using the HRG-Py-Pd nanocatalyst, the highest conversion of 99% is achieved in the coupling reaction of 4-bromoanisol and acrylic acid in an aqueous solution in a relatively short period of time (3 h), with less quantity of catalyst (3 mg). Comparatively, pristine Pd NPs delivered lower conversion (∼92%) for the same reaction required a long reaction time and a large amount of catalyst (5.3 mg). Indeed, the conversion of the reaction further decreased to just 40% when 3 mg of Pd-NPs was used which was sufficient to produce 99% conversion in the case of HRG-Py-Pd. On the other hand, HRG-Pd did not deliver any conversion and was ineffective even after using a high amount of catalyst and a longer reaction time. The inability of the HRG-Pd to promote coupling reactions can be attributed to the agglomeration of Pd NPs which reduced the dispersion quality of the catalyst in water. Therefore, the high aqueous stability of HRG-Py-Pd due to smart functionalization can be utilized to perform other organic transformations in water which was otherwise not possible.

Preventing bacteria from adhering to material surfaces is an important technical problem and a major cause of infection. One of nature’s defense strategies against bacterial colonization is based on the biohalogenation of signal substances that interfere with bacterial communication. Biohalogenation is catalyzed by haloperoxidases, a class of metal-dependent enzymes whose activity can be mimicked by ceria nanoparticles. Transparent CeO2/polycarbonate surfaces that prevent adhesion, proliferation, and spread of Pseudomonas aeruginosa PA14 were manufactured. Large amounts of monodisperse CeO2 nanoparticles were synthesized in segmented flow using a high-throughput microfluidic benchtop system using water/benzyl alcohol mixtures and oleylamine as capping agent. This reduced the reaction time for nanoceria by more than one order of magnitude compared to conventional batch methods. Ceria nanoparticles prepared by segmented flow showed high catalytic activity in halogenation reactions, which makes them highly efficient functional mimics of haloperoxidase enzymes. Haloperoxidases are used in nature by macroalgae to prevent formation of biofilms via halogenation of signaling compounds that interfere with bacterial cell–cell communication (“quorum sensing”). CeO2/polycarbonate nanocomposites were prepared by dip-coating plasma-treated polycarbonate panels in CeO2 dispersions. These showed a reduction in bacterial biofilm formation of up to 85% using P. aeruginosa PA14 as model organism. Besides biofilm formation, also the production of the virulence factor pyocyanin in is under control of the entire quorum sensing systems P. aeruginosa. CeO2/PC showed a decrease of up to 55% in pyocyanin production, whereas no effect on bacterial growth in liquid culture was observed. This indicates that CeO2 nanoparticles affect quorum sensing and inhibit biofilm formation in a non-biocidal manner.

Two mono-nuclear axially distorted octahedral copper(II) complexes have been prepared and characterized via FT-IR, UV–Visible, elctrochemical, electron spin resonance and powder and single crystal XRD techniques. The complexes consist of a phenanthroline and two carboxylate ligands each bonded in bidentate fashion. Carboxylates are ortho-nitro-2-phenyl acetate (L1) and para-chloro-2-phenyl acetate (L2). Structural study showed that both complexes possess Jahn–Teller distorted octahedral geometry. The bulk purity was assessed from the matching experimental and simulated powder XRD spectra. The results of spectroscopic techniques are consistent with each other. ESR data revealed single electron occupancy of dx2 − y2 orbital with 2B1g as ground state typical of tetragonally distorted octahedral geometry. Electrochemical solution study showed diffusion controlled electron transfer processes with diffusion co-efficient values of 10.323 × 10–8 cm2s–1 and 0.972 × 10–8 cm2s–1 for 1 and 2. Complexes exhibited excellent DNA-binding activity studied via UV–Visible spectroscopy, cyclic voltammetry, florescence spectroscopy and viscometry yielding Kb values of 1.871 × 104 M–1 (1) and 1.577 × 104 M–1 (2), 0.38 × 104 M–1 (1) and 6.39 × 104 M–1 (2) and 2.1 × 106 M–1 (1) and 2.0 × 06 M–1 (2), respectively, for the first three techniques. Complexes possess good antifungal activity against three fungal strains.

The solvothermal synthesis of hierarchically organized hematite nanoparticles is reported. The nanoparticles with an average diameter of ≈ 55 nm consist of self-assembled small sub-particles with average sizes of ≈ 5 nm. They were synthesized by controlling the humidity and reaction temperature under solvothermal conditions using an especially designed set-up in a Teflon-lined stainless steel autoclave. Under optimized humidity conditions, the morphology of the nanoparticles changed from self-assembled poly-crystalline to monocrystalline nanoparticles by varying the temperature from 80 to 150 °C. The overall size of the nanoparticles and sub-particles’ domain remained the same, i.e., 55 nm and 5 nm for the product synthesized at 80 °C and 120 °C. Hematite nanoparticles prepared at 150 °C temperature consisted of single-domain nanoparticles with an average size of ≈ 60 nm. The size and crystallinity of these nanoparticles was monitored by transmission electron microscopy (TEM) and powder X-ray diffractometry (PXRD). The optical properties of the as-synthesized hematite nanoparticles were measured by UV-visible spectroscopy. Nanoparticles with an absorption in the visible range were tested for the photocatalytic degradation of organic pollutant using methylene blue as model compound. Hematite nanoparticles synthesized at lower temperatures, i.e., 80 °C, showed higher photocatalytic activities compared with nanomaterials synthesized at 120 °C and 150 °C.

Herein, we report novel macromolecular prodrugs (MPDs) of flurbiprofen (FLB) onto a cellulose ether, hydroxypropylcellulose (HPC). The FLB was activated with a powerful acylation reagent carbonyldiimadazole (CDI) in N,N′ dimethylacetamide (DMAc) solvent at room temperature. Imidazolide of FLB generated in situ reacts at 80 °C for 24 h with pre-dissolved HPC to prepare HPC-FLB conjugates. The resultant MPDs of FLB showed moderate to high degree of substitution (DS: 0.35–1.3) with good yield (70–82%). Structures were thoroughly characterized using FTIR, UV and NMR spectroscopic analyses. The pharmacokinetic studies showed that the t1/2 and tmax values of FLB from HPC-FLB conjugate were increased substantially as compare to standard FLB indicates enhanced bioavailability of drug after conjugate formation. Remarked anti-inflammatory activity of the HPC-FLB conjugate was also observed.

This investigation is focused on the synthesis of two halo-functionalized crystalline Schiff base (imine) compounds: (

Graphene-based nanocomposites with inorganic (metal and metal oxide) nanoparticles leads to materials with high catalytic activity for a variety of chemical transformations. Graphene and its derivatives such as graphene oxide, highly reduced graphene oxide, or nitrogen-doped graphene are excellent support materials due to their high surface area, their extended π-system, and variable functionalities for effective chemical interactions to fabricate nanocomposites. The ability to fine-tune the surface composition for desired functionalities enhances the versatility of graphene-based nanocomposites in catalysis. This review summarizes the preparation of graphene/inorganic NPs based nanocomposites and their use in catalytic applications. We discuss the large-scale synthesis of graphene-based nanomaterials. We have also highlighted the interfacial electronic communication between graphene/inorganic nanoparticles and other factors resulting in increased catalytic efficiencies.

In the current work, a symmetrical tetradentate Schiff base ligand (H2L) derived by the condensation of methoxy-salicylaldehyde with substituted phenylenediamine is used to prepare nickel (II) and palladium (II) complexes. The chemical structures of the synthesized compounds were investigated with the help of combustion analysis and spectrophotometrically using FT-IR and 1H NMR. H2L and its nickel (II) complex were obtained in pure crystalline form, and hence, these compounds were characterized by diffraction analysis. It was evident from single-crystal X-ray diffraction analysis (SC-XRD) that the ligand was doubly deprotonated (L−2) and coordinated with the Ni(II) ion via ONNO-donor sites, and a distorted square planar geometry was achieved. Interestingly, the complex also attaches a solvent molecule (DMF) through its electronegative O atom with the H atom of DMF through hydrogen bonding. The molecular structure of the synthesized compounds was further validated with the help of density functional theory (DFT) using the B3LYP/Def2-TZVP level of theory. Furthermore, the Pd(II) complex was tested for Suzuki–Miyaura cross-coupling reactions and the results showed better catalytic activity in mild conditions concerning the traditionally available catalysts.

Structural modification of lead compounds is a great challenge in organic synthesis. Introduction of different functional groups not only modify the structure of starting material but also improve their biological activeness. Small synthetic molecules are favored in spite of the reality that majority of drug molecules derived from natural sources, are in vogue. In the present work, acetamide derivatives were synthesized using chloroacetyl chloride. After synthesizing targeted series of acetamide derivatives these compounds were further modified using different amines including 2-aminobenzene thiol, benzyl amine, benzene 1,4-diamine, 4-amino-1,5-dimethyl-2-phenyl-1 H -pyrazol-3(2 H)- one, 4-aminophenol, hydrazine and 4-amino- N- (5-methylisoxazol-3-yl)benzenesulfonamide. All of these synthesized compounds were characterized by FT-IR, 1 H NMR, 13 C NMR and X-ray crystallography. The compounds were assessed for their anti-bacterial activity using disc diffusion method against Staphylococcus aureus and Escherichia coli . The compounds were found to exhibit comparable activity to the standard drug used. This was further supported by molecular docking studies using bacterial DNA gyrase and Topoisomerase II targets causing bacterial death as they are major bacterial proteins known to be involved in transcription and replication process. Results proved that the compound 2b was the most efficacious antimicrobial compound among the synthesized set of compounds. To tackle the growing drug resistance acetamide based functionalities can be regarded as the active lead compounds to target different drug resistance microorganism.

The optoelectrical and magnetic characteristics of naturally existing iron-based nanostructures, especially hematite and magnetite nanoparticles (H-NPs and M-NPs), gained significant research interest in various applications, recently. The main purpose of this Review is to provide an overview of the utilization of H-NPs and M-NPs in various environmental remediation. Iron-based NPs are extensively explored to generate green energy from environmental friendly processes such as water splitting and CO

The asymmetric unit of the title compound, [Tm

Preventing bacteria from adhering to material surfaces is an important technical problem and a major cause of infection. One of nature's defense strategies against bacterial colonization is based on the biohalogenation of signal substances that interfere with bacterial communication. Biohalogenation is catalyzed by haloperoxidases, a class of metal-dependent enzymes whose activity can be mimicked by ceria nanoparticles. Transparent CeO