Synthesis,computational, experimental antimicrobial activities and theoretical molecular docking studies of (E)-4-((4-hydroxy-3-methoxy-5-nitrobenzylidene) amino)-N-(thiazole-2-yl) benzenesulfonamide

The compound (E)-4-((4-hydroxy-3-methoxy-5-nitrobenzylidene) amino)-N-(thiazole-2-yl) benzene sulfonamide (5NVTH) was synthesized and characterized by the Infrared, UV-Visible, and NMR analysis. The compound theoretical study was done by using DFT. The compound molecular structure and geometry were defined using DFT. Topological studies, like ELF, LOL, ALIE, and RDG studies, were done with the Multiwfn-3.8 to find the main binding areas and weak interactions in the molecule. Using the IEFPCM solvation model was used to study the calculated UV-Visible spectrum. The HOMO-LUMO, MEP, and NBO properties were carried out in the gas phase. The NBO calculations are used to study how charges move between and within the molecule and the stability of this molecule. A pharmacological analysis is done using an online tool like Swiss-ADME, to see if the molecule could be a potential drug candidate; this evaluation looks at the drug-likeness, ADME, and eco-friendly toxicity properties of the 5NVTH molecule. Auto-dock suite is used for molecular docking study and discovery studio is used for analyzing the docking results. Antimicrobial activity studies indicate the compound Klebsiella pneumonia and Candida albicans have good antibacterial and antifungal activity compared to positive control and other microorganisms.     

Targeted Delivery of Anticancer Drug Loaded Charged PLGA Polymeric Nanoparticles Using Electrostatic Field

Pure positive electrostatic charges (PPECs) show suppressive effect on the proliferation and metabolism of invasive cancer cells without affecting normal tissues. PPECs are used for the delivery of drug-loaded polymeric nanoparticles (DLNs) capped with negatively charged poly(lactide-co-glycolide) (PLGA) and Poly(vinyl-alcohol) PVA into the tumor site of mouse models. The charged patch is installed on top of the skin in the mouse models' tumor region, and the controlled selective release of the drug is assayed by biochemical, radiological, and histological experiments on both tumorized models and normal rats' livers. It is found that DLNs synthesized by PLGA show great attraction to PPECs due to their stable negative charges, which would not degrade immediately in blood. The burst and drug release after less than 48h of this synthesized DLNs are 10% and 50%, respectively. These compounds can deliver the loaded-drug into the tumor site with the assistance of PPECs, and the targeted-retarded release will take place. Hence, local therapy can be achieved with much lower drug concentration (conventional chemotherapy [2 mg kg⁻¹] versus DLNs-based chemotherapy [0.75 mg kg⁻¹]) with negligible side effects in non-targeted organs. PPECs have many potential clinical applications for advanced-targeted chemotherapy with the lowest discernible side effects.     

MULTILINEAR CALDER(O)N-ZYGMUND OPERATOR ON MORREY TYPE SPACES——In Memory of Professor Yongsheng Sun

In this paper, the authors study the boundedness of a class of multi-sublinear operators on the product of Morrey, Herz-Morrey and generalized Morrey spaces, respectively. As their special cases, the corresponding results of multilinear Calderón-Zygmund operator can be obtained.     

Application of enriched stable 196Hg isotope for monitoring the stability of total mercury in water samples

A novel tool for the investigation of stability of total mercury in water samples is presented. The study focuses on the application of enriched ¹⁹⁶Hg stable isotopic reagent for the stability studies. Natural abundance of ¹⁹⁶Hg in water samples is only 0.15%. Thus, the use of the ¹⁹⁶Hg isotope spike represents a major advantage, when it can be assumed that all the measured isotope is the same as is accurately added by the analyst, and the change in its mass concentration can be followed simply and reliably. Tests were carried out with industrial waste water and two type of the natural water. Cold vapour (CV) inductively coupled plasma mass spectrometer (ICP-MS) technique was applied for the mercury measurements. Monitoring was continued for approximately 100 days. It is commonly advised that the measurement for total mercury in water samples should be carried out within 14 days. In this study the samples were observed to be stable for more than three months, if they were stored at a temperature of 4–6°C. The results of this stability study were in line with the guidance presented in EPA standard 1631. However, the samples were noticed to be stable for a much longer time than is presented in the standard method ISO 17852.     

Synthesis,Spectroscopy, Semi‐empirical and Biological Activities of Organotin(IV) Complexes with o‐Isopropyl Carbonodithioic Acid

New organotin(IV) complexes have been synthesized by treating potassium o‐isopropyl carbonodithioate with R₂SnCl₂/R₃SnCl in 1 : 2/1 : 1 M/L ratio. All complexes have been characterized by IR and NMR (¹H, ¹³C) spectroscopy. IR results shows that ligand acts as bidentate which is also confirmed by semi‐empirical study. NMR data reveals four coordinated geometry in solution. Computed positive heat of formation shows that complex 5 is thermodynamically unstable. UV/visible spectroscopy was used to assess the mode of interaction and binding of the complexes with DNA which shows that complex 5 exhibits higher binding constant as compared to complex 3 . In protein kinase inhibition assay, compound 3 was found most active, while other biological activities shows that triorganotin(IV) complexes are biologically more active as compared to diorganotin(IV) complexes.     

A kinetic and mechanistic study of dinuclear Pt(II) 2,2′:6′,2″-terpyridine compounds bridged with polyethyleneglycol ether flexible linkers

A series of dinuclear Pt(II) complexes bridged with polyethyleneglycol ether of the type [ClPt(tpy)O(CH₂CH₂O)_n(tpy)PtCl]Cl₂ where n = 1 (Ptdteg), 2 (Ptdtdeg), 3 (Ptdtteg), 4 (Ptdttteg), and linker-free complex, (Ptdt) (where tpy = 2,2′:6′,2″-terpyridine), were synthesized and characterized to investigate the role of bridging polyethyleneglycol ether linker on the substitution reactivity of dinuclear Pt(II) complexes. Substitution reactions were studied using thiourea nucleophiles, viz. thiourea (TU), 1,3-dimethyl-2-thiourea (DMTU), 1,1,3,3-tetramethyl-2-thiourea (TMTU) under pseudo-first-order conditions as a function of concentration and temperature by conventional stopped-flow reaction analyzer. The reactions gave single exponential fits following the rate law k_obs = k₂[Nu]. Introduction of polyethyleneglycol ether linker decreases the electrophilicity of the platinum center and the whole complex. The results obtained indicate that the rate of substitution is controlled by both electronic and steric hindrance which increases with the length of the linker. Experimental results are supported by density functional theory calculations and structures obtained at B3LYP/LANL2DZ level. The order of the reactivity of the nucleophiles is TU > DMTU > TMTU. The magnitude and the size of the enthalpy of activation and entropy of activation support an associative mode of mechanism, where bond formation in the transition state is favored.     

PBL教学模式在中美高校化学实验课教学中应用的对比研究

因课程设置、学情等不同, PBL教学模式在中美高校化学实验课的实施过程中各具特色。本文从教材、课程考核、师资培训、研究机构和基金等4个角度客观分析PBL教学模式在中美2国高校化学实验课应用中的差异,并在此基础之上提出,应该客观公正地看待这种差异,树立文化自信。     

高中化学新手熟手专家教师教学策略知识比较*

以“原电池”教学主题为载体自编调查问卷,选取河北省90位在职高中化学教师进行教学策略知识(Knowledge of instructional strategies,简称KoIS)测查。应用单因素方差分析与多重比较LSD法,从教学策略与表征的选择、应用、调整、反馈以及评价等5个维度对新手、熟手和专家教师KoIS之间的差异及其表现特征进行了比较和分析,并据此提出相关建议,为促进高中化学教师KoIS水平提升提供借鉴和参考。     

面向高阶思维培养的自主型实验教学模式的设计与实践*

基于教育现代化、发展“互联网+教育”、培养创新性人才的指导思想,结合“超星学习通”网络平台与实验课堂的优势,设计了面向高阶思维培养的“预习自测-讲授讨论-自主实践-总结反思”的四段自主型实验教学模式,并应用于化学与化工类专业分析化学实验课程的教学实践。该实验教学模式增加了学生自主学习时间,培养了学生“分析、综合、评价和创造”等高阶思维能力,提高了实验课程的教学效率,为高等院校实践实验教学的改革提供了参考依据。     

Histone deacetylase (HDAC) inhibitor curcumin upregulates mitochondrial uncoupling protein1 (UCP1) and mitochondrial function in brown adipocytes,in-silico study and screening natural drug library

Mitochondrial dysfunction has been associated with diverse pathological conditions globally. Specifically, in adipose tissues, mitochondrial dysfunction is the primary cause of obesity and obesity-related illnesses. An existing drugs such as atorvastatin and other lipid-lowering drugs demonstrated adverse effects and initiated other diseases. Thus, we need to explore new methods to prevent and treat obesity. In this study, we used the cell screening method to identify several natural compounds that increase adipocyte UCP1 gene expression. The identified drug Curcumin was evaluated in cell models and the In-silico model. We found curcumin is an active compound of turmeric belonging to Zingiberaceae (ginger family), which activates the Nrf2 mechanism. Curcumin potentially endorses the expression of UCP1 in the brown adipocyte in vitro cellular model. Curcumin plays an important role that modulating mitochondrial function and improving mitochondrial DNA quantification, ATP production, and cell viability. We have established an efficient in vitro cell experiment system to study the metabolic regulation of UCP1. The in-silico model revealed curcumin-UCP1 interaction. Curcumin, via enhancing mitochondrial activity, could be a helpful therapeutic molecule against metabolic disorders or obesity-related diseases. Curcumin will be the subject of more research in both human and murine models, which will provide novel therapeutic pathways for the treatment of metabolic illnesses by modulating the control of mitochondrial function.