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441.
Aruna Chhikara Praveen K. Roayapalley Hiroshi Sakagami Shigeru Amano Keitaro Satoh Yoshihiro Uesawa Umashankar Das Swagatika Das Edgar A. Borrego Cristina D. Guerena Clare R. Hernandez Renato J. Aguilera Jonathan R. Dimmock 《Molecules (Basel, Switzerland)》2022,27(19)
Two series of novel unsymmetrical 3,5-bis(benzylidene)-4 piperidones 2a–f and 3a–e were designed as candidate antineoplastic agents. These compounds display potent cytotoxicity towards two colon cancers, as well as several oral squamous cell carcinomas. These compounds are less toxic to various non-malignant cells giving rise to large selectivity index (SI) figures. Many of the compounds are also cytotoxic towards CEM lymphoma and HL-60 leukemia cells. Representative compounds induced apoptotic cell death characterized by caspase-3 activation and subG1 accumulation in some OSCC cells, as well as the depolarization of the mitochondrial membrane potential in CEM cells. A further line of inquiry was directed to finding if the SI values are correlated with the atomic charges on the olefinic carbon atoms. The potential of these compounds as antineoplastic agents was enhanced by an ADME (absorption, distribution, metabolism, and excretion) evaluation of five lead molecules, which revealed no violations. 相似文献
442.
Chakali Ayyanna;Sujatha Kuppusamy;Pasala Praveen Kumar; 《Macromolecular Symposia》2024,413(2):2300078
Flavonoids are a diverse group of naturally occurring plant compounds that are primarily composed of phenols in their free form or glycosides. Flavonoid medicines are primarily composed of 2-phenyl-g-benzopyrone. This family consists of monomeric flavanols, flavanones, anthocyanidins, flavones, isoflavonoids, and flavonols. The study's main objective is to review the newly discovered natural flavones and flavanols, as well as the biological and pharmacological actions of these essential flavonoids. As per the available data, 3-hydroxy flavone plays a vital role in the prevention of a range of diseases. Research studies have confirmed that 3-hydroxyflavone has a broad range of pharmacological properties like therapeutic effects against pain, inflammation, oxidative stress; hepatotoxicity, hypertension, ulcerogenesis, allergy, platelet dysfunction, microbes, fungi, viruses, rhinovirus, malaria, and carcinogens. 3-Hydroxy flavone has limited utility because of their poor solubility and bioavailability. This has led to the search for new drug delivery methods, such as nanoparticles. To get over these problems, it would be preferable to administer 3-hydroxyflavone via the biocompatible nanoparticles. It is expected that nanoparticles will improve the solubility of 3-hydroxyflavone, enhance its therapeutic properties and facilitate its transport to the brain. 相似文献
443.
Praveen Kumar Mupparapu Narasimha Swamy Thirukovela Sadanandam Gullapelli Mohan Kurra Srinivas Gali Namratha Vaddiraju 《Journal of heterocyclic chemistry》2021,58(6):1379-1387
In this study, a series of novel geminal bis 1,2,3-triazoles linked to 2H-furo[2,3-d][1,3]thiazine-2,4,5(1H,6H)-trione ( 3a-3m ) were prepared in one pot starting from 5-Acetyl-4-Hydroxy-1,3-thiazine-2,6-dione ( 1 ) to 6,6-diazido-2H-furo[2,3-d][1,3]thiazine-2,4,5(1H,6H)-trione ( 2 ) followed by Cu(I)-catalyzed azide-alkyne cycloaddition. The synthesized compounds were further explored for in vitro cytotoxic activity against PC3, A549, MCF-7, and HeLa cell lines and results revealed that the five compounds 3c , 3d , 3g , 3l , and 3m have displayed comparable in vitro cytotoxic activity with the standard drug Etoposide. 相似文献
444.
Ravinder Kumar Dr. Shagufi Naz Ansari Rakesh Deka Praveen Kumar Dr. Mohit Saraf Dr. Shaikh M. Mobin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(55):13669-13698
Covalent-organic frameworks (COFs), being a new member of the crystalline porous materials family, have emerged as important materials for energy storage/conversion/generation devices. They possess high surface areas, ordered micro/mesopores, designable structures and an ability to precisely control electro-active groups in their pores, which broaden their application window. Thanks to their low weight density, long range crystallinity, reticular nature and tunable synthesis approach towards two and three dimensional (2D and 3D) networks, they have been found suitable for a range of challenging electrochemical applications. Our review focuses on the progress made on the design, synthesis and structure of COFs and their composites for various energy applications, such as metal-ion batteries, supercapacitors, water-splitting and solar cells. Additionally, attempts have been made to correlate the structural and mechanistic characteristics of COFs with their applications. 相似文献
445.
Sauvik Chatterjee Dr. Piyali Bhanja Dr. Dibyendu Ghosh Dr. Praveen Kumar Dr. Sabuj Kanti Das Dr. Sasanka Dalapati Prof. Asim Bhaumik 《ChemSusChem》2021,14(1):408-416
Photoelectrochemical water-splitting offers unique opportunity in the utilization of abundant solar light energy and water resources to produce hydrogen (renewable energy) and oxygen (clean environment) in the presence of a semiconductor photoanode. Zinc oxide (ZnO), a wide bandgap semiconductor is found to crystallize predominantly in the hexagonal wurtzite phase. Herein, we first report a new crystalline triclinic phase of ZnO by using N-rich antidiabetic drug metformin as a template via hydrothermal synthesis with self-assembled nanorod-like particle morphology. We have fabricated a heterojunction nanocomposite charge carrier photoanode by coupling this porous ZnO with a covalent organic framework, which displayed highly enhanced photocurrent density of 0.62 mA/cm2 at 0.2 V vs. RHE in photoelectrochemical water oxidation and excellent photon-to-current conversion efficiency at near-neutral pH vis-à-vis bulk ZnO. This enhancement of the photocurrent for the porous ZnO/COF nanocomposite material over the corresponding bulk ZnO could be attributed to the visible light energy absorption by COF and subsequent efficient charge-carrier mobility via porous ZnO surface. 相似文献
446.
Praveen Kumar Khursheed Ahmad Janardan Dagar Eva Unger Shaikh M. Mobin 《ChemElectroChem》2021,8(16):3150-3154
In recent years, development of lead (Pb) free perovskite solar cells (PSCs) has attracted the scientific community because of their stability in air and less toxic nature. Antimony (Sb) based perovskite like-materials such as (CH3NH3)3Sb2I9 and (NH4)3Sb2I9 have been employed as light absorbers and showed promising features for photovoltaic applications. Herein, we have utilized (NH4)3Sb2I9 as light absorber for the construction of Pb free PSCs. Moreover, we have employed a modified two step procedure for the preparation of (NH4)3Sb2I9. The developed Pb free PSCs device ( FTO/CL-TiO2/m-TiO2/(NH4)3Sb2I9/HTM/Au ) exhibited enhanced power conversion efficiency (PCE) of 0.42 % with open circuit voltage (Voc) of 945 mV. 相似文献
447.
Humaira Kalsoom Miguel Vivas-Cortez Muhammad Idrees Praveen Agarwal 《Entropy (Basel, Switzerland)》2021,23(11)
In this work, first, we consider novel parameterized identities for the left and right part of the -analogue of Hermite–Hadamard inequality. Second, using these new parameterized identities, we give new parameterized -trapezoid and parameterized -midpoint type integral inequalities via -quasiconvex function. By changing values of parameter , some new special cases from the main results are obtained and some known results are recaptured as well. Finally, at the end, an application to special means is given as well. This new research has the potential to establish new boundaries in comparative literature and some well-known implications. From an application perspective, the proposed research on the -quasiconvex function has interesting results that illustrate the applicability and superiority of the results obtained. 相似文献
448.
Malik Bataineh Mohammad Alaroud Shrideh Al-Omari Praveen Agarwal 《Entropy (Basel, Switzerland)》2021,23(12)
Fuzzy differential equations provide a crucial tool for modeling numerous phenomena and uncertainties that potentially arise in various applications across physics, applied sciences and engineering. Reliable and effective analytical methods are necessary to obtain the required solutions, as it is very difficult to obtain accurate solutions for certain fuzzy differential equations. In this paper, certain fuzzy approximate solutions are constructed and analyzed by means of a residual power series (RPS) technique involving some class of fuzzy fractional differential equations. The considered methodology for finding the fuzzy solutions relies on converting the target equations into two fractional crisp systems in terms of ρ-cut representations. The residual power series therefore gives solutions for the converted systems by combining fractional residual functions and fractional Taylor expansions to obtain values of the coefficients of the fractional power series. To validate the efficiency and the applicability of our proposed approach we derive solutions of the fuzzy fractional initial value problem by testing two attractive applications. The compatibility of the behavior of the solutions is determined via some graphical and numerical analysis of the proposed results. Moreover, the comparative results point out that the proposed method is more accurate compared to the other existing methods. Finally, the results attained in this article emphasize that the residual power series technique is easy, efficient, and fast for predicting solutions of the uncertain models arising in real physical phenomena. 相似文献
449.
The present study concerns the investigation of different mixing models for use in the transported probability density function (PDF) modeling of turbulent (reacting) spray flows. The modeling of the turbulent mixing and other characteristic scalar variables such as gas enthalpy using transported (joint) PDFs has become an important method to describe turbulent (reacting) spray flows since the evaporation process causes the PDF of the mixture fraction to deviate from the widely used β function, which is typically used in models for turbulent gas flows. In the PDF transport equation, the molecular mixing does not appear in closed form so that modeling strategies are required. For gas combustion, the interaction-by-exchange-with-the-mean (IEM) model, the modified Curl (MC) model, and the Euclidean minimum spanning tree (EMST) models are used. More recently, a new mixing model, the PSP model, which is based on parameterized scalar profiles has been developed. The present study focuses on the use and analysis of the IEM, MC and PSP models for turbulent spray flames. For this purpose, the models are reconsidered with respect to the evaporation process that must be included and evaluated if spray combustion is considered. For model evaluation, turbulent ethanol/air spray flames are simulated, and the results are compared to experimental data by A. Masri, University of Sydney, Australia. 相似文献
450.