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Synthesis of Quinazoline Derivatives
No full textEfficient synthesis of heterocyclic has always been a very important task in drug discovery. Most of the drugs contain heterocycles to provide an interface between chemistry and biology. Among the various heterocyclic compounds, quinazoline, a heterocyclic compound, offers multiple advantages like pyrimidine, pyridine, piperidine, imidazole, morpholine, quinoline, purine, etc. Many research groups have demonstrated numerous synthesis techniques to harvest the advantage of quinazoline. Therefore, it is necessary to understand the various aspects of the development techniques of quinazoline as industry-oriented application. Various methodologies have been recently developed for the formation of quinazoline moiety. In this review article, the synthetic methods of quinazoline derivatives are classified based on metal-catalysed and miscellaneous synthetic aspects
Priestia endophytica mediated biosynthesis of zinc oxide nanoparticles: characterization, biocompatibility and anticancer activity
No full textThe current study focused on biogenic synthesis of Zinc Oxide Nanoparticles (ZnO NPs) using Priestia endophytica and evaluated their potential anticancer activity. The ZnO NPs were characterized by various techniques including Scanning electron microscopy (SEM), UV-Visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and Energy dispersive spectroscopy (EDS) analysis. The optical properties measured using UV spectroscopy showed a peak at 319nm. The FTIR reveals the presence of various functional groups, including Zn–O, C–H, C=O, and C=C and –OH on ZnO NPs. In contrast, XRD indicates the wurtzite hexagonal crystalline structure. SEM images show the spherical or quasi-spherical morphologies with an average size range of 20–70nm with high purity. After successful characterization, the anticancer effects were tested against A549 and HeLa cell lines. Results showed anticancer activity against both cancer cell types, with 50% cell viability at 91.5±1.2 and 127±5.6µg ml−1 for A549 and HeLa cells, respectively. In conclusion, the findings from this study suggest that eco-friendly and biogenic ZnO NPs may offer a promising nanoformulation for cancer treatment
Controlling plasmonic charge carrier flow at a nanoparticle-molecule interface using ligand chemistry
No full textControlling charge-carrier flow at a metal-molecule interface is crucial for developing efficient plasmonic catalysts. Here, we demonstrate that the overlap of ligands’ LUMO/HOMO with Au electronic states governs the flow of charge carriers induced by surface plasmon resonance (SPR) or interband excitation. A (p)NO2-Ph-SH functionalized gold nanoprism (NO2-TP) substrate exhibited a 4-fold higher hydrogen production rate compared to a (p)Br-Ph-SH-functionalized substrate (Br-TP) under interband excitation (440 nm). Conversely, under SPR excitation (740 nm) the Br-TP substrate exhibited a 10-fold higher hydrogen production rate than a NO2-TP substrate. Theoretical calculations reveal that the HOMO of (p)NO2-Ph-SH aligns effectively with the Au d-band, promoting d-band hole transport. In contrast, the LUMO of (p)Br-Ph-SH exhibits better overlap with the sp band above the Fermi level, enabling efficient hot electron transport. These findings provide general guidelines to optimize plasmonic catalysts for different excitation wavelengths
Asymptotic Behaviour Of The Least Energy Solutions To Fractional Neumann Problems
No full textWe study the asymptotic behaviour of the least energy solutions to the following class of nonlocal Neumann problems: 0} \text{in } \Omega, \\ { \mathcal{N}_{s}u=0 } \text{in } \mathbb{R}^{n}\setminus \overline{\Omega}, \end{cases} \end{align*} ]]> where is a bounded domain of class, <![CDATA[ ]] and is the nonlocal Neumann derivative. We show that for small the least energy solutions of the above problem achieve an-bound independent of Using this together with suitable-estimates on we show that the least energy solution achieves a maximum on the boundary of for d sufficiently small
Copper phosphide quantum dot: A bifunctional catalyst for electro- and photochemical transformation of biomass-derived 5-hydroxymethylfurfural
No full textThe extensive reliance on fossil fuel enables the harnessing of biomass-derived compounds, such as 5-Hydroxymethylfurfural (HMF), for the sustainable production of valuable products. Copper-based materials are gaining interest as heterogeneous electrocatalysts due to their abundance and tuneable redox states. Herein, we report copper phosphide (Cu3P) quantum dot as a bifunctional electrocatalyst for oxidation and reduction of HMF into 2,5-Furandicarboxylic acid and 2,5-bis(hydroxymethyl)furan, respectively, which serve as the platform chemicals. We have achieved faradaic efficiency of 57 % in 1 M KOH and 45 % in pH 4 PBS at 10 and −2 mA cm−2 current density for HMFOR and HMFRR, respectively. This work presents the scope of replacing anodic and cathodic reactions of conventional water electrolysis with less energy cost, easy catalyst synthesis, and ambient conditions
On de Rham cohomology of Drinfeld modules of rank 2
No full textPreviously, using the theory of delta characters for Drinfeld modules, one constructed a finite free R-module H(E) with a semilinear operator on it, and hence a canonical z-isocrystal Hδ(E) was attached to any Drinfeld module E that depended on the invertibility of a differential modular parameter γ. In this paper, we prove that γ is invertible for a Drinfeld module of rank 2. As a consequence, if E does not admit a lift of Frobenius and K is the fraction field of the ring of definition, we show that H(E)∅K is isomorphic to HdR(E) ∅ K and the isomorphism preserve the canonical Hodge filtration. On the other hand, if E admits a lift of Frobenius, then H(E)∅K is isomorphic to the subobject Lie(E)∗ ∅ K of HdR(E) ∅ K. The above result can be viewed as a character theoretic interpretation of de Rham cohomology
Inverse effect of a covalently attached electron-proton transfer mediator in the oxygen reduction reaction
No full textIn this work, the electron-proton transfer mediator (EPTM) BQ/H2Q was covalently attached to the salophen ligand (Sal-H2Q), and the ORR activity of its iron complex Fe(Sal-H2Q) was compared with that of the salophen complex of iron without the EPTM, using acetic acid as the external proton source in acetonitrile. The rate of the ORR was found to be much higher for Fe(Sal), giving a peak current of 222 μA, while for Fe(Sal-H2Q), it was 115 μA at a similar potential. Selectivity measurements revealed that both catalysts show selective water formation. This observation holds for other solvent systems as well. The findings in this study are contrary to the general observation that the covalent attachment of BQ/H2Q EPTM enhances the ORR reactivity
Geometrical engineering of nearly fully cation-selective 2D angstrom-scale ionic diode membranes for highly efficient osmotic energy conversion
No full textAchieving a membrane with perfect ion selectivity, high energy conversion efficiency, and high ionic flux is crucial towards ultrahigh osmotic energy generation, but still challenging due to the inherent tradeoff between membrane's selectivity and permeability. Herein, we propose the strategy of asymmetric sub-nanoconfinement by designing a two-dimensional (2D) lamellar sub-nanofluidic MXA membrane using Ti3C2Tx MXene and highly space charged aramid nanofibers. By employing geometric engineering and integrating the membrane into an epoxy-acrylic device with in-plane orientation, the asymmetric MXA membrane exhibits a strong ionic diode effect with a rectification ratio up to 37-fold. Remarkably, the synergy of surface and space charges in 2D sub-nanofluidic channels renders the MXA membrane nearly fully cation-selective, independent of the applied concentration gradient. Benefiting from these fantastic features, an ultrahigh power of 9.7 W m−2 along with an ultrahigh energy conversion efficiency of ∼49.8% (approaching the theoretical upper limit of 50%) can be achieved under a 500 mM/10 mM NaCl gradient, surpassing that of the existing 2D sub-nanoscale osmotic energy generators. Moreover, the proposed device can exhibit exceptional long-term structural and performance stability for over 140 h. This study presents an approach for creating a 2D angstrom-scale ionic diode membrane with enhanced ionic rectification, selectivity, efficiency, and stability for highly efficient osmotic energy harvesting