European Journal of Chemistry

A series of single-phase R-type hexagonal ferrites with the composition Sr_1-xMg_xFe₄Sn₂O₁₁ (x = 0.0, 0.1, 0.2, 0.3) were manufactured using the auto-combustion sol-gel method sintered at 800 °C. The objective of this work was to study the effect of Mg additives on the structural, magnetic, and permeability properties of the synthesised material. The X-ray diffraction patterns revealed that all prepared samples have hexagonal structures. The scanning electron micrographs revealed the platelet-like structure of the grains, which would help enhance the magnetic permeability of the materials. Magnetic parameters were investigated in the range of applied field ±12.5 kOe. The hysteresis loops revealed the paramagnetic nature of all the synthesised samples. With the substitution of Mg contents, the maximum magnetization increased from 1.05 to 2.62 (emu/g) and the remanence from 0.02-0.09 (emu/g), while the coercivity also increased. The magnetic permeability was determined over the frequency range of 20 Hz to 20 MHz. The magnetic permeability of the synthesized hexagonal ferrites is enhanced due to the presence of grains having a platelet-like structure. Furthermore, the particle size calculated using Langevin equations varied in the range of 4.7 to 6.5 nm. The calculated magnetic permeability properties make this synthesised ferrite material useful for super-high-frequency devices.

The study of different lignocellulosic materials for second-generation biofuels is one of the trending topics today because of the high demand for fuels for transportation and electricity generation. Coffee husk is presented as one study option considering that only 10% of the coffee fruit is used for coffee production. The pretreatment of the coffee husk with sulfuric acid (3 or 6%) and citric acid (6 or 12%) was compared using two methodologies. The first had reaction condition time (50, 70, 90, and 1440 min) and temperature (70 and 90 °C), while the second had autoclave conditions (121 °C, 14.696 psi, 60 min). The comparison was made to find the best methodology for acid pretreatment before enzymatic hydrolysis. The best result of the reduction of sugars (17.017%) and glucose yield (3.882%) was found with 6% C₆H₈O₇ in autoclaving (121 °C, 14.696 psi, 60 min) with hydrolysis conditions of 72 h, 150 rpm, 50 °C, and using cellulases from Trichoderma reesei.

Polyacrylamide (PAM) is a biodegradable polymer with good lubricity in friction reduction. However, there is insufficient guidance on the dosage of PAM and poor rheological information on the effects of temperature and pH. This study aimed to investigate the characterization of the material and rheological analysis regarding the effects of concentration, pH, and temperature of PAM. In material characterization, PAM has been shown to offer hydrophilic surfaces. In a rheological study, 1000 ppm PAM was the critical association concentration, as the rheological properties below 1000 ppm PAM were superior. This was due to the dispersion stability effect caused by the polymer concentration. Additionally, a low concentration of polymer contributes to bridging flocculation with an unstable rheological profile and low association networking. When the polymer concentration is further increased to the saturated adsorption level, the rheological profile of PAM above 1000 ppm is significantly affected as a result of the alternation from steric stabilization to depletion flocculation in a polymer system. Furthermore, the rheological performance of PAM was significantly affected by temperature and pH, showing better performance after heating to 60 °C and at pH = 10. Future studies can further develop modified PAM with specific additives at an optimized temperature and pH to investigate the rheological performance of drilling.

The mixture of cis and trans-[RuCl₂(dppe)₂] (dppe: 1,2-bis-(diphenylphosphino)ethane) was prepared and the interaction with CT-DNA was evaluated by several methods, including UV-vis DNA spectroscopic titration, viscosity, and electrochemical studies. Investigation suggests that [RuCl₂(dppe)₂] interacts moderately with CT-DNA. Interestingly, the cis- and trans-isomers interact differently with DNA, as proved by the square-wave voltammetry studies. Finally, the crystal structure of trans-[RuCl₂(dppe)₂]Cl was obtained from an electrochemical solution and studied in detail, which presents a distorted octahedral geometry and interatomic parameters different from those found in the trans-[RuCl₂(dppe)₂] complex. Crystal data for C₅₂H₄₈Cl₄P₄Ru: triclinic, space group P-1 (no. 2), a = 9.240(3) Å, b = 10.9290(18) Å, c = 11.993(3) Å, α = 78.707(11)°, β = 86.712(13)°, γ = 82.598(13)°, V = 1177.1(5) Å³, Z = 1, T = 293(2) K, μ(MoKα) = 0.732 mm^-1, Dcalc = 1.467 g/cm³, 8434 reflections measured (6.934° ≤ 2Θ ≤ 51.986°), 4607 unique (R_int = 0.0973, R_sigma = 0.1171) which were used in all calculations. The final R₁ was 0.0537 (I > 2σ(I)) and wR₂ was 0.1347 (all data).

The green technique is a unique way to produce functional nanoparticles. We examined the green synthesis of Ag nanoparticles (O-AgNPs) by the extract of Oxalis corniculata. Green-synthesized O-AgNPs were accomplished by monitoring critical factors such as concentration, pH, reaction time, and temperature. Several analytical techniques, including scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction analysis, and UV-Vis spectroscopy, were applied to characterize O-AgNPs. The SEM analysis showed O-AgNPs with a spherical shape and an average size of 33.57 nm. The XRD pattern indicated the face-centered cubic (fcc) structure of the prepared O-AgNPs. The anticancer activity of the synthesized O-AgNPs was investigated in MCF-7 (breast) and AGS (gastric) cell lines, indicating high anticancer effects against selected cell lines. The growth of all selected bacteria containing Gram+ and Gram- was inhibited by O-AgNPs. O-AgNPs showed greater inhibition in comparison to conventional antibiotics. As a result, our green synthesized AgNPs using plant extracts exhibited anticancer and antibacterial activities.

The objective of the present study was to examine the chemical compositions of Salvia coccinea oleoresins prepared in methanol and petroleum ether. GC-MS analysis of Salvia coccinea methanolic oleoresin (SCMO) and Salvia coccinea ether oleoresin (SCEO) resulted in the identification of 15 and 12 constituents, comprising 84.7 and 81.2% of the total composition, respectively. Both SCMO and SCEO varied in their chemical composition in terms of quantity, namely, oleic acid (22.3-25.9%), palmitic acid (8.9-8.4%), stigmasta-3,5-dien-7-one (3.4-11.8%), stigmasterol acetate (3.5-5.3%), neophytadiene (4.8-1.7%), phytol (1.6-7.8%) and phthalic acid (2.1-3.1%). In addition to the qualitative differences between SCMO and SCEO concomitantly, both oleoresins were examined for their pesticidal activities. Oleoresins demonstrated significant nematicidal activity against Meloidogyne incognita, insecticidal activity against Lipaphis erysimi, antifungal activity against Curvularia lunata, and antibacterial activity against Staphylococcus aureus. For nematicidal activity, SCMO and SCEO exhibited a high mortality of 65.66±1.69 and 54.33±1.24 and egg hatching inhibition of 26.33±1.20and 33.33±1.24 at 200 μg/mL. Similarly, SCMO and SCEO exhibited excellent insecticidal activity with 94.87±1.44 % and 86.75±1.85 %   mortality at 1000 μg/mL. However, both oleoresins exhibited moderate antifungal and antibacterial activities compared to standards. Due to the quantitative difference in chemical composition and the presence of several phytoconstituents that were absent in SCEO, SCMO displayed stronger pesticidal effects than SCEO. To estimate the binding energy and structure-activity relationships between chemical constituents and pesticidal activities, in silico molecular docking and ADME/Tox studies have also been performed using a web-based online tool. On the basis of the present study, it is inferred that the herb Salvia coccinea might be a good source of phytochemicals and can be used for the development of herbal-based pesticides/formulations after proper clinical trials.

In this study, gold nanoparticles were synthesized using the fruit extract of Sambucus ebulus (S. ebulus) as a reducing, capping, and stabilizing agent. Biogenic synthesis of gold nanoparticles (Au nanoparticles) was accomplished using S. ebulus fruit extract in the presence of hydrogen tetrachloroaurate(III) trihydrate at a temperature of 65 °C and the solution stirred at 400 rpm. The characterization of the synthesized nanoparticles (SE-AuNPs) was performed using different analytical methods, such as scanning electron microscopy (FE-SEM), energy dispersion X-ray spectroscopy (EDS), Fourier transform infrared (FT-IR), X-ray diffraction analysis (XRD), and UV-vis spectroscopy. A strong absorption peak at 565 nm confirmed the formation of the gold nanoparticle. On the basis of the electron microscopy results, AuNPs were mostly spherical with an average size of 116.2 nm. The cubic crystalline structure of the prepared nanoparticles was confirmed using the XRD pattern and the average crystallite size was obtained at 28.471 nm. FT-IR analysis confirmed the presence of functional groups in the plant extract for the synthesis of nanoparticles. SE-AuNPs showed good antibacterial activity against Gram-positive and Gram-negative bacteria tested and exhibited potent antileishmanial activity. Furthermore, SE-AuNPs showed excellent antioxidant activity that inhibited DPPH radicals with an IC₅₀ value of 21.976 µg/mL. The prepared AuNPs acted to degrade methyl orange (MO), which was performed in sodium borohydride and visible light.

Initiation and progression of several diseases by post-translational histone modifications are considered a worldwide problem. Enhancer of Zeste Homologue 2 (EZH2), which belongs to the histone-lysine N-methyl transferase (HKMT) family, has been emphasised as a promising target for cancer therapy. It is a major challenge for the scientific community to find novel approaches to treating this disease. In this study, a series of 51 derivatives of the benzofuran and indole families, previously experimentally evaluated against HKMT, was used to develop the best model with promising anticancer activity. The multiple linear regression (MLR) method, implemented in QSARINS software, was used with a genetic algorithm for variable selection. According to QSARINS, the model with two descriptors (minHBint4 and Wlambdal.unity) was found to be the best and its parameters fit well, and its validation was well established. The applicability domain was also validated for this model. Furthermore, its robustness (R² = 0.9328), stability (Q²_LOO = 0.9212, Q²_LMO = 0.9187), and good predictive power (R²_ext = 0.929) were also verified. Hence, this model was assumed to have predictive HKMT anticancer activity for designing active compounds. Molecular docking was also performed to identify binding interactions, and new molecules with better predicted biological activity (pIC₅₀) were designed. The binding energy of the three designed compounds demonstrated higher binding activity at the target receptor, followed by complex stability, determined by a 100 ns molecular dynamics simulation and binding free energy calculation. Density functional theory (DFT) and pharmacokinetic analyses also confirmed their drug-like properties. Finally, it can be declared that the proposed tools allow rapid and economical identification of potential anti-HKMT drugs (anticancer drugs) for further development.

In the present investigation, the corrosion inhibition potency of five pyridine derivatives was computationally simulated and investigated by utilizing the Density Functional Theory (DFT) technique using a basis set of B3LYP/6-31++G (d,p). The predicted corrosion inhibition capacity was shown to improve in the order of 6-(trifluoromethyl) nicotinic acid > 4-(trifluoromethyl) nicotinic acid > N-methyl-4-chloropyridine-2-carboxamide > 2-chloro-6-trifluoromethylnicotinic acid > methyl 2-aminopyridine-4-carboxylate. Anticorrosion potentials were predicted using quantum chemical variables such as energy gap (∆E) i.e. HOMO-LUMO, ionization potential (I), electron affinity (A), proportion of electrons transmitted (∆N), hardness (η), softness (σ) and electronegativity (χ) of chemical species. It was often observed that the corrosion inhibiting rate improved with enhancement of E_HOMO, σ, and reduced E_LUMO, ∆E and η. Additionally, the electrostatic potential (ESP) mapping revealed that the heteroatoms, including the oxygen and nitrogen atoms, were the regions of anticipated electrophilic attack. This meant that atoms of oxygen and nitrogen could form bonds between the metallic substrate atoms and the investigated inhibitors. With the findings obtained, 4-methyl-2-aminopyridine-4-carboxylate showed the highest E_HOMO (-0.23167 eV), softness (12.40694 eV^-1) and the lowest E_LUMO (-0.7047 eV), energy gap (0.1612 eV) and hardness (0.15107 eV), therefore revealed the excellent corrosion inhibiting attribution for several crucial metals and alloys, including aluminum, mild steel, stainless steel, zinc, brass, copper, etc.

This study explained a green synthesis of silver nanoparticles (AgNPs) using Nepeta pogonosperma extract and evaluated their antibacterial activity. Optimization of the temperature, concentration, pH, and reaction time was established to produce silver nanoparticles. The best condition was 10 mM AgNO3, pH = 14, temperature 85 °C, and reaction time 24 hours. The formation of silver nanoparticles was confirmed by colour-changing, UV-vis, FE-SEM, EDX, XRD, FT-IR, and DLS analysis. The prepared AgNPs had a spherical shape with an average size of 51.21±0.02 nm. In addition, our biofabricated nanoparticles displayed potential antibacterial activity against the tested strains. The MIC value of 1.17 µg/mL was determined against strains of Pseudomonas aeruginosa, Acinetobacter baumannii, and Escherichia coli and 2.34 µg/mL against Staphylococcus aureus, Klebsiella pneumoniae, Proteus mirabilis and Enterococcus faecalis. Furthermore, AgNPs exhibited excellent antifungal effects against Candida albicans strains (0.073 μg/mL). In general, N. pogonosperma played an important role in reducing Ag(+1) to Ag(0) and the production of Ag(0) with suitable surface features in combination with efficient biological activities.

Hydrazine and its derivatives, as harmful substances, seriously risk the health of humans and the environment. On the basis of the admirable luminescent properties and low biological harmfulness of the biphenyl moiety, a biphenyl moiety can be combined with a naphthalene ring via the chalcone scaffold easily traced by a nucleophilic group. Therefore, biphenyl chalcones (BPCs) decorated with various naphthalene systems as fluorescent sensors for hydrazine are synthesised by Claisen-Schmidt condensation. The present work describes the comparative studies of two different protocols for the synthesis of three different BPCs. The structures of all novel BPCs were investigated by FT-IR, NMR, and HRMS spectroscopy. These BPCs show a red shift with a fluorescent peak and an enhancement in intensity with increasing solvent polarity from hexane to methanol. Methanol shows strong fluorescence emission; therefore, methanol is used as the solvent in hydrazine sensing experiments. The BPCs display fluorescent variation from yellow to blue fluorescence after binding with hydrazine. These BPCs sensors are able to identify hydrazine in a fast response rate and 5 min response time. The screening study of hydrazine in various soil samples by prepared BPCs is highly efficient. A study of the pH dependence of these probes shows excellent sensitivity in the pH range of 5 to 10.

The present study involves the synthesis of macrocyclic lactones by the esterification of unsaturated fatty acids (oleic acid, undecenoic acid, and erucic acid) with unsaturated alcohols (allyl alcohol, prop-2-ene-1-ol, oleyl alcohol, and undecenol) followed by a ring closing metathesis reaction employing Grubbs' second generation catalyst (1.0-1.5 mmol). The structure of the compounds was confirmed by ¹H NMR, ¹³C NMR, FT-IR, and ESI-Mass spectral studies. The antibacterial activity of the synthesised lactones was evaluated. The larger ring-sized lactone, namely, erucic acid lactone, exhibited excellent antibacterial activity against three bacterial cell lines, namely, Staphylococcus aureus, Staphylococcus epidermidis, and Bacillus subtilis. Undecenoic acid-based lactones exhibited excellent antibacterial activity selectively against only Staphylococcus epidermidis. The assay of macrolactones for their in vitro anticancer activity was carried out by MTT for different cancer cell lines, namely, human prostate epithelial cancer cells (ATCC HTB-81), HepG2 derived from hepatic cancer cells (ATCC HB-8065), SKOV3 derived from human ovarian cancer cells (ATCC HTB-77), MDAMB-231 derived from human breast cancer cells (ATCC HTB-26) and Chinese hamster ovarian (CHO-K1) cell lines. The molecules selectively exhibited anticancer activity against Chinese hamster ovarian (CHO-K1) cell lines. Among macrolactones, (E)-oxacyclotridec-11-en-2-one (MALUN) was more active and its activity was much higher compared to others and on par with the reference standard Mitomycin C. This was followed by (E)-oxacyclotricos-14-en-2-one (MOLER) and (E)-oxacyclononadec-10-en-2-one (MOLOH). The fatty acid-based cyclic lactones with selective antibacterial and anticancer activities can be further explored for a variety of pharmaceutical formulations.

The azo Schiff base ligand was synthesised, along with its Ni(II) complex, by diazotisation of salicylaldehyde with 4-nitroaniline in accordance with the accepted literature approach. Using a variety of spectroscopic techniques, the resulting complex is analysed both quantitatively and qualitatively (Elemental analysis, FT-IR spectroscopy, UV-VIS spectroscopy, ¹H NMR, etc.). Spectral measurements of the complex revealed a mole ratio of 1:1. The non-electrolytic nature of the complex is confirmed by molar conductance investigation. The unique azo compound had a tetrahedral shape as a result of the tetra coordination of two phenolic oxygen and two imine nitrogen. The ability of the metal complexes to bind DNA was examined using absorption spectroscopy, fluorescence spectroscopy, viscosity tests, and thermal denaturation methods. Experimental research suggests that complexes bind to DNA through intercalation.

Some 2H-chromen-2-one and imine derivatives have been synthesized through a one-pot condensation of aldehydes, diethyl malonate, and amine compounds. The compounds obtained have been characterized using FTIR, NMR, GC-MS, and elemental analysis. The single-crystal X-ray structure of 3-[piperidine-1-carbonyl]-2H-chromen-2-one (2) has been presented. Compound 2, recrystallized in the monoclinic space C2/c (no. 15), a = 16.654(15) Å, b = 8.789(7) Å, c = 18.460(18) Å, β = 102.89(5)°, V = 2634(4) Å³, Z = 8, T = 296(2) K, μ(MoKα) = 0.091 mm^-1, Dcalc = 1.298 g/cm³, 17626 reflections measured (4.528° ≤ 2Θ ≤ 57.446°), 3321 unique (R_int = 0.0313, R_sigma = 0.0257) which were used in all calculations. The final R₁ was 0.0441 (I > 2σ(I)) and wR₂ was 0.1329 (all data). The experimental bond lengths, bond angles, and other topological properties of compound 2 were compared with the DFT calculated results, the comparison showed good agreement with each other with varying level deviations. The energy levels of HOMO and LUMO, as well as the global chemical reactivity descriptors of representative compound 2, have been presented. A discussion of the Hirshfeld surface analysis of compound 2 has been carried out to provide insight into its structural properties.

Chalcones are versatile scaffolds for the synthesis of various heterocyclic systems with commercial utility. This work describes the synthesis of five novel chalcone derivatives. Syntheses were performed by a simple one-pot, straightforward Claisen-Schmidt condensation catalyzed with pyrrolidine and KOH. The chalcones were prepared by condensation of 4-formylbenzonitrile with different aromatic ketones at room temperature. The structures of all compounds have been investigated by FT-IR, NMR, and HR-MS spectroscopy. In addition, one chalcone structure was characterized by single-crystal XRD study. Crystal data for C₂₁H₁₅NO₂ (Ch2): monoclinic, space group P2₁/c (no. 14), a = 6.5694(3) Å, b = 33.2697(15) Å, c = 7.4516(4) Å, β = 97.563(2)°, V = 1614.47(14) ų, Z = 4, T = 293(2) K, μ(MoKα) = 0.083 mm^-1, D_calc = 1.289 g/cm³, 16000 reflections measured (4.898° ≤ 2Θ ≤ 49.99°), 2822 unique (R_int = 0.0249, R_sigma = 0.0196) which were used in all calculations. The final R₁ was 0.0484 (I > 2σ(I)) and wR₂ was 0.1257 (all data). The absorption maxima of all novel products were evaluated by UV-visible spectroscopy. These well-established structures of all newly prepared chalcone scaffolds with reactive functional groups (i.e. nitrile and 2-propenone) can be exploited as a crucial intermediate in the synthesis of new heterocyclic scaffolds with fluorescence and other applications.

Current water management does not fully account for potential crisis situations when dealing with drinking water. It is important to focus on an efficient and at the same time economic approach to water management, including consideration of the ecological aspect. One way is to focus on the use of alternative sources of water. The possibilities of purified wastewater or captured rainwater indicate a certain direction. Current technical possibilities and scientific knowledge offer many opportunities. The priority is to find and increase the way to limit the use of drinking water for economic activities. The more intensive use of alternative water sources is still in the background and neglected. This article provides information on this issue and encourages deeper ecological and economic reflexion.