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Phenothiazine derivative N-(4-bromophenyl)-10H-phenothiazine-10-carboxamide (BPC), a novel compound is selected for the present study based on the reported effectiveness of phenothiazine towards neurodegenerative diseases. Synthesis and characterization of BPC are carried out in the present work. To comprehend the electronic and structural aspects of BPC, quantum chemical studies are performed. Computational aspects using the density functional theory method using B3LYP/6–31 G ++(d,p) as a basis set are studied for the geometry optimization of the molecule. To analyze the reactivity, stability, and intramolecular interactions of the compound frontier orbital molecular analysis, molecular electrostatic potential distribution, and Fukui function are implemented. Calculations have been made to determine the electrophilic and nucleophilic descriptors of the title compounds by Fukui function evaluations on atomic charges. To visualize and quantify the localization of electrons and molecular orbitals in the molecule, electron localization function, localized orbital locator analysis and orbital localization analysis are carried out for a better understanding of chemical bonding. Basin Analysis is used for analysis of the nature of chemical bonds and interactions. To understand bond strengths, hyperconjugation, and reactivity natural bond orbital analysis is performed.

Carboxylate appended biochar BCKA was synthesized by a two-step functionalization of leached rice straw biochar using ethyl 2-bromoacetate/K₂CO₃/DMF and hydrolysis to furnish the modfied biochar. The modified biochar was characterized using proximate analysis, CHNS, SS CPMAS ¹³C NMR, FESEM, FTIR, XPS, BET, and zeta potential. Biochar BCKA was optimized for pH and dose, respectively, as 7 and 0.2 g/L for methylene blue (MB) adsorption with a contact time of 6 h at 298 K. MB removal up to 98% from 20 mg/L dye solution, using BCKA as adsorbent pH 7, 298 K. The nonlinear fit to Langmuir, Freundlich, Temkin, SIPS, and D-R adsorption isotherm showed a good fit with correlation coefficients (R²) 0.970, 0.969, 0.988, 0.984, and 0.983, respectively, and maximum MB adsorption (q_m) of 261 mg/g. Thermodynamic parameters for the adsorption of MB using BCKA were 38.72 kJ/mol (∆H°), 225.42 J/mole K (∆S°), and negative ∆G° confirming the spontaneity driven by entropy. Kinetic studies showed good nonlinear fit to pseudo-second order (R² 0.967), intraparticle diffusion (R² 0.977), and Elovich equation (R² 0.958) with chemisorption-based interaction between BCKA and MB. Chemisorption, particularly ion exchange on the surface of BCKA with MB, is inferred from the D-R isotherm and kinetic analysis. Column breakthrough studies showed Thomas model fit with q_t 267.09 mg/g, and efficiency >80% was retained for two cycles of MB adsorption.

Photocatalytic performance of titanium dioxide under visible light was optimized by preparing heterophase compounds (containing two or more phases) by hydrolysis method using TiCl₄ as a precursor with different concentrations (0.5, 0.7, 1, and 2) to adjust condensation modes of Ti⁴⁺. The structural and textural properties of the synthesized TiO₂ multiphase were fully characterized by XRD, Raman scattering, FTIR, BET, MEB-EDX, XPS, diffuse UV–vis, and EIS spectroscopy. The increase of TiCl₄ amount precursor has a significant effect on the heterophase junctions of TiO₂ structure and more especially on textural and structural properties. The best specific surface area (131 m²/g) is observed for the sample at high Ti-content (2 in Ti⁴⁺). The anatase phase (79%) is detected only for 0.5 in Ti⁴⁺ sample. However, both rutile (R) and brookite (B) phases are present in 0.7, 1, and 2 Ti-contents. On the one hand, the band gap of 2.9 eV allows titanium dioxide to be active under visible light. In addition, the presence of rutile/brookite heterophase junction contributes significantly to the improvement of active sites for photocatalytic reaction. The separation efficiency of photogenerated electrons and holes contributes to photocatalytic evolution performance under visible light for hydrogen production. The optimal sample (0.7 content in Ti⁺⁴ species) which presents in its structure 52% of rutile and 46% of brookite phases presented the highest photocatalytic activity with a 230 µmol/h of hydrogen generation, attributed to the heterophase junctions R52/B46, highly pore size 20.60 nm, and relatively small bandgap energy 2.974 eV. This work opens new horizons on the creation and study of a multiphase TiO₂ that works under visible light in the fields of renewable energies and various other fields.

A facile, efficient, and environmentally friendly protocol for the solvent-free synthesis of antipyrine- linked quinoline derivatives catalyzed by CeO₂–TiO₂ nanocatalyst under ultrasonication is developed. Antipyrine derivatives are involved in various synthetic processes and exhibit valuable biological activities, such as antibacterial, anti-inflammatory, antioxidant, and anticancer properties. Biowaste- derived CeO₂–TiO₂ nanoparticles have been synthesized using outer covering calyx leaves extract of Physalis peruviana fruits and utilized for the construction of biologically important antipyrine derivatives by the multicomponent reaction in short reaction time with excellent yield. The nanocatalyst was characterized by FT-IR, powder X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and electron dispersion spectroscopy (EDS). The functionalized nanoparticles show excellent reusability without any significant loss in catalytic activity. The hot filtering experiment shows that there is no noticeable leaching or boomerang effect and that the catalysis is heterogeneous in nature. All synthesized compounds underwent screening for antibacterial activity against selected microorganisms, and their antioxidant activity was assessed using DPPH (2,2-diphenyl-1-picrylhydrazyl). Some of the synthesized compounds exhibited promising results in both screenings.

A series of ordered mesoporous silicas (MCM-41, SBA-15 and KIT-6) were successfully synthesized and modified with nickel by incipient wetness impregnation method. The supports and catalysts were characterized by N₂ adsorption-desorption, XRD, TEM, H₂-TPR, UV vis-DR, XPS, ICP and Py FT-IR techniques. All the materials were evaluated in the Knoevenagel condensation reaction between vanillin and malononitrile under microwave irradiation. The catalytic results show the key role that the chosen porous structure plays in the deposition of the active phase and its catalytic behaviour. Thus, by designing a suitable mesoporous catalyst it was possible to carry out such Knoevenagel condensation to obtain 2-(4-hydroxy-3-methoxybenzylidene) malononitrile through a highly efficient and environmentally friendly process, without solvents and reducing reaction times by employing microwave heating.

A highly diastereoselective total synthesis of Eliglustat has been accomplished starting from a readily available D-serine. This novel route involves a four-step telescoped process to afford the keto intermediate (4) in 74% overall yield. The diastereoselective reduction of 4 using sodium borohydride provides the alcohol, a key intermediate 5, with excellent selectivity (>99 dr) and yield (95%). The total synthesis of Eliglustat from D-serine has been accomplished in ten steps with an overall yield of 21%. This process not only gives a desirable yield but also avoids the use of hazardous conditions.

We rationally designed and successfully developed novel dipeptidic proline amide–isothiouronium catalysts for asymmetric conjugate addition reactions between various aldehydes and nitroolefins, which generated 1,4-addition products with up to 95% yields, 92:8 syn-diastereoselectivity, and 96% enantiomeric excess. The catalysts, which were prepared via simple methylation of the corresponding thiourea, can provide the desired enantiomeric syn-1,4-adducts by exchanging the configuration of the N-terminal proline moiety.

Because of remarkable reactivity and strong electron-electron correlation effects, the precise prediction of ground state energy and chemical reactivity of hydride ion is an essential objective in quantum chemistry. Leveraging variational quantum algorithms offers a promising avenue for studying molecular properties using current noisy intermediate-scale quantum devices. This work utilises the variational approach to anticipate the ground state, reactivity, and single-electron detachment energy of the three-body hydride ion. We investigated both Hardware-Efficient Ansatz (HEA) and Chemistry-inspired ansatz based on a Unitary Coupled Cluster (UCC) on both noiseless and noisy IBM simulators. Modern error-mitigating techniques, such as Zero-Noise Extrapolation (ZNE) with unitary folding and measurement error mitigation, have been implemented to significantly reduce errors in noisy environments. This study contributes to our understanding of the quantum computational nuances of the hydride ion and addresses the question of whether quantum computers can retain the correlation energies for these correlated ions.

In our efforts to design mono-carbonyl analogues of curcumin with potential antiplasmodial activity, diarylidenecyclopentanone (DACP) derivatives, Ia–Iu and II–V, have been synthesized and characterized using ¹H NMR, ¹³C NMR, IR, UV–Vis, and mass spectrometry. Structure of one of these DACPs has been verified by single crystal XRD. At the outset, all 25 DACPs were first screened at 12.5 µM for their in vitro antiplasmodial activity against the chloroquine (CQ)-sensitive Pf3D7. The three most potent compounds (In, It, and Ik) were further tested at <10 µM concentrations against Pf3D7, PfINDO (CQ resistant), and PfMRA-1240 (Artemisinin resistant) strains for determination of their IC₅₀s and resistance indices. The drug profile of the DACPs was found to be very promising, with the most active compound It (IC₅₀ 1.39 µM against PfINDO) showing a selectivity index of ∼17 tested using HUH-7 and HEK-293T mammalian cell lines. Molecular docking studies with Pf pyridoxal synthase showed a good correlation between docking scores of DACPs and in vitro antiplasmodial activity. Further, high conformity with Lipinski's parameters indicates that these DACPs are promising antiplasmodial lead compounds.