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In this study, a mathematical model is developed for analyzing the time-dependent magneto-convective flow and heat transfer characteristics of an electrically conducting (functional) third-grade Reiner-Rivlin non-Newtonian nanofluid from a moving or stationary hot cylinder in the presence of magnetic field and thermal radiation. A well-tested convergent Crank–Nicolson type finite difference algorithm is employed to solve the transformed, nonlinear boundary value problem. The Tiwari-Das nanofluid volume fraction model is adopted for nanoscale effects and the Rosseland algebraic flux model for radiative heat flux effects. It has been shown that the shape of nanoparticles remarkably contributes to the enhancement of heat transfer. Several metallic nanoparticle types such as Al2O3, Cu, and TiO2 are examined. It is found from the investigation that the viscoelastic nanofluid with TiO2 nanoparticles results in more heat transfer than the other nanoparticles. Lower velocity and higher temperature values are computed at transient conditions with a higher third-grade fluid parameter for the flow of nanofluid (Al2O3-SA). The plots of transient friction and heat transfer coefficients are visualized at the surface of a hot cylinder. The tabulated heat transfer coefficient is comparatively more for the moving cylinder than the stationary cylinder. Detailed validation of results of the numerical scheme with previous studies is included. The simulations find applications in coating deposition (enrobing) of magnetic nanomaterial at high temperatures, functional nanomaterial synthesis, etc. [ABSTRACT FROM AUTHOR]

A two‐dimensional numerical model has been framed to investigate the effect of buoyancy forces on magnetized free convective Walters‐B fluid flow over a stretching sheet with Soret effect, heat radiation, thermal source/sink, and viscous dissipation. The current physical model is developed based on the stretching sheet geometry. The impact of Lorentz force on the nonlinear system is investigated and considered in the velocity equation. The influence of thermal radiation, heat source/sink, viscous dissipation, and Joule heating is considered in the energy equation. The effect of Soret parameter and chemical reaction on mass transfer is accounted in the concentration equation. The current physical model is governed by the highly coupled nonlinear system of partial differential equations. Owing to the inadequacy in the analytical techniques, the obtained governing equations are solved by using the bvp4c Matlab function via similarity transformations approach. Numerical computations are performed for the varying values of physical parameters, which are expressed in terms of tables and graphs. Magnifying viscoelastic parameter decays the velocity profile and enhances the thermal and concentration fields. Enhancing free convection parameters diminishe the velocity fields and magnifies the thermal profile. Thermal field magnifies with enhancing thermal radiation parameter and Eckert number. Enhancing the Soret number raises the concentration field. Also, the bvp4c Matlab function adequately simplifies the highly nonlinear coupled system of equations occurring in nature. The present similarity solutions presented in this paper coincides with previously published results in the literature. [ABSTRACT FROM AUTHOR]

A series of 30 small hybrid molecules are synthesized inspired from Combretastatin A‐4 (CA‐4), where ethylene‐bridge of CA‐4 is replaced with two five‐membered heterocyclic rings, viz. isoxazoline and 1, 2, 3‐triazole. These are joined by a methylene linker, with substitutions at A and B – ring position of CA‐4. The new molecular entities have shown significant cytotoxicity to cancer cell from the IC50 0.49 μM–3.17 μM with 1‐((4,5‐Dihydro‐3‐(2,5‐dimethoxyphenyl)isoxazol‐5‐yl)methyl)‐4‐(4‐methoxyphenyl)‐1H‐1,2,3‐triazole displayed IC50 0.422±0.07 μM for A‐549 ‐lung cancer cell line and IC50 0.498±0.03 μM for MDA‐MB‐231‐breast cancer cell line. The western blot analysis, confocal staining and also by in vitro tubulin polymerization assay established the target specificity of the molecules as a tubulin polymerization inhibitor. Molecular docking & Molecular dynamics studies confirmed the binding interaction patterns of these molecules at the Colchicine binding site of tubulin and have correlated the observed experimental result with variation in structure satisfactorily. [ABSTRACT FROM AUTHOR]

Chemical investigation on Orthosiphon diffusus lead to isolation of two new substituted polychiral 5, 6-dihydro-α-pyrones, orthodiffenes E-F ( 5-6 ) which were characterized from the detailed studies of their 1D and 2D NMR spectra. Isolated molecules orthodiffenes E-F ( 5-6 ) along with previously isolated, reported orthodiffene A-D ( 1-4 ) molecules were subjected to in silico studies and analysed for anticancer target Topoisomerse I-B − DNA complex. Orthodiffene D and E are giving noteworthy observations while all isolated molecules are showing a pattern of binding in active pocket similar to each other however, different from Camptothecin, an anticancer agent. Orthodiffene A-C have comparable cytotoxicity to Camptothecin, which we have earlier reported. [ABSTRACT FROM AUTHOR]

Abstract: A short practical synthesis of a new natural product based scaffold (6), based on antitrypanosomal and antimalarial compounds isolated from different Plakortis species is described. The scaffold contains a peroxide unit that is surprisingly stable to chemical manipulation elsewhere in the molecule, enabling it to be elaborated into a small library of derivatives. It is stable to ozonolysis, reductive work-up with dimethylsulfide and the Wittig reaction with stabilized phosphorus ylides. The scaffold along with its Wittig analogues has displayed low to sub-micro molar (0.2–3.3μM) antitrypanosomal activity. [Copyright &y& Elsevier]

Abstract: Chemical investigation on Orthosiphon diffusus resulted in the isolation of four relatively rare, novel polychiral furanopyrans, orthodiffenes A–D (1–4) which were characterized from detailed studies of their 1D and 2D NMR spectra. The X-ray crystallographic analysis of orthodiffene A (1) was accomplished. The in vitro cytotoxic activity of orthodiffenes A–C (1–3) was tested against Jurkat and HL-60 cells using camptothecin as a positive control. Orthodiffenes A (1) and B (2) showed comparable activity to camptothecin against HL-60 and Jurkat cells, respectively. [ABSTRACT FROM AUTHOR]

Abstract: A stereoselective method has been developed for the synthesis of (Z)- and (E)-allyl iodides from Baylis–Hillman adducts using polymethylhydrosiloxane (PMHS) and iodine in chloroform at room temperature. In addition, the reagent system has been utilized for the iodination of benzylic alcohols selectively. [Copyright &y& Elsevier]

Abstract: Benzimidazoles have been efficiently synthesized in high yields by treatment of 1,2-phenylenediamine with aldehydes using (bromodimethyl)sulfonium bromide at room temperature. [Copyright &y& Elsevier]

Abstract: A synthesis of the unusual cyclobutane-quinolinone alkaloids melicodenines C, D and E by intermolecular [2+2] cycloaddition is described. [Copyright &y& Elsevier]

Abstract: Treatment of Baylis–Hillman adducts with iodosobenzene (PhI presence of a catalytic amount of KBr in water at room temperature afforded the corresponding acyloxiranes in good yields. [Copyright &y& Elsevier]

The paper reports the development of Cu-doped NiCo 2 O 4 ternary inverse spinel oxides through microwave-assisted hydrothermal method as effective catalysts for alkaline hydrogen evolution reaction (HER). The effective and controlled doping of Cu to NiCo 2 O 4 lattice by the partial replacement of Ni2+/Ni3+ with Cu+/Cu2+ results in the fine-tuning of structural, morphological, and electronic characteristics, favourable for electrocatalytic HER. The study effectively correlates the influence of variation in the percentages of Cu-doping on the material properties and thereby the electrocatalytic characteristics. The experimental results indicate that Cu 0.10 Ni 0.90 Co 2 O 4 electrode having optimum Cu-doping (10%) as the best electrocatalyst with the lowest onset potential for hydrogen evolution (242.7 mV) and reduced overpotential (72.5 mV) values by following a Volmer – Heyrovsky mechanism during HER. The improvement in HER performance after Cu-doping is due to the generation of greater number of active sites and reduction in electronic band gap. The present work advantageously utilises the scope of microwave-assisted transition metal doping strategy to fine tune the physicochemical and electronic characteristics, favourable for electrocatalytic HER, and this may pave a new way for tuning the electrochemical properties of metal oxides for various applications. • Microwave-assisted hydrothermal synthesis is used effectively to develop Cu-doped NiCo 2 O 4. • Cu-doping to NiCo 2 O 4 lattice creates more oxygen vacancies and improves electronic conductivity. • Cu 0.10 Ni 0.90 Co 2 O 4 with 10% Cu-doping exhibits promising electrocatalytic activity towards HER. • Cu-doped NiCo 2 O 4 follows Volmer – Heyrovsky mechanism during alkaline HER. [ABSTRACT FROM AUTHOR]

A mild and efficient method has been developed for the synthesis of alkyl and alkenyl iodides from alkenes and alkynes using polymethylhydrosiloxane (PMHS) and iodine in chloroform at room temperature. The reagent system generates hydrogen iodide which regioselectively adds to the alkenes and alkynes. [ABSTRACT FROM AUTHOR]

Abstract: Polymethylhydrosiloxane (PMHS) in combination with (bromodimethyl)sulfonium bromide or NBS has been utilized for the first time for reductive bromination of aromatic aldehydes at room temperature to afford the corresponding benzyl bromides in excellent yields. [Copyright &y& Elsevier]

Natural products, natural product-inspired molecules and natural product derivatives have contributed around 79% to the new chemotherapies against the most complex, deadly disease, cancer. In this study, a series of novel isoxazoline derivatives of Goniodiol diacetate (fused bicyclic pyranone isoxazoline derivatives)- a natural product derivative, were synthesized with quantitative yield as a single regioisomer by 1,3 - dipolar cycloaddition reaction with different aldoximes. The regiospecific product formed was confirmed by NOESY study and single-crystal X-ray diffraction. The regiospecificity of the product formation was further explained by coefficients of selected atomic orbitals in frontier molecular orbitals and natural population analysis (NPA in eV) of dipolarophile and dipole by density functional theory studies. All the derivatives have demonstrated anti-cancer activity selectively in human breast cancer (MDA-MB-231), ovarian cancer (SKOV3), prostate cancer (PC-3) and colon cancer (HCT-15) cell lines with EC 50 < 10 μM. Additionally, Annexin V/PI assay and cell cycle analysis on selected potent compound 3 f exhibited tuned apoptotic response & necrosis compared to standard Vincristine and showed cell growth arrest at the S phase. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: A simple, efficient and rapid method has been developed for high-yielding regioselective nuclear monobromination of aromatic and heteroaromatic compounds using NBS in the presence of sulfonic-acid-functionalized silica at room temperature. The catalyst works under heterogeneous conditions and can be recycled. [Copyright &y& Elsevier]

Abstract: A facile and versatile method for the chemoselective Boc protection of amines has been developed by a treatment with (Boc)2O in the presence of sulfonic-acid-functionalized silica as a catalyst. The method is general for the preparation of N-Boc derivatives of aliphatic (acyclic and cyclic), aromatic, and heteroaromatic amines; primary and secondary amines; aminols, amino-esters; and sulfonamides. The catalyst works under heterogeneous conditions and can be recycled. [Copyright &y& Elsevier]