Ratio Design of Docetaxel/Quercetin Co-Loading-to-Nanocarrier: Synthesis of PCL–PEG–PCL Copolymer,Study of Drug Release Kinetic and Growth Inhibition of Human Breast Cancer (MCF-7) Cell Line

Russian Journal of Applied Chemistry - The present study aimed to design PCL–PEG–PCL copolymer as novel nanocarrier for co-loading of docetaxel (DTX) and quercetin (Qu) drugs and...     

Tetrakis [<Emphasis Type="Italic">N</Emphasis>-(2-pyridyl) sulfonamide] di palladium: synthesize,X-ray diffraction,antibacterial properties and as a novel binuclear Pd-complex for coupling reactions

The N-(2-pyridyl) 4-toluene sulfonamide as a free ligand (PTS) was prepared from the reaction of 2-amino pyridine and 4-toluenesulfonyl chloride in the presence of potassium hydroxide solution 1 M as a base and THF was used as a solvent. The complex tetrakis [N-(2-pyridyl) sulfonamide] di palladium (1) (Pd₂L₄) was also prepared from the reaction of PdCl₂(CH₃CN)₂ using (PTS) in the presence of NaOH 0.5 M and its application in Heck and Suzuki reactions. This complex consists of a binuclear unit consisting of four ligands linked to two palladium atoms via the nitrogen of pyridines ring and the nitrogen of sulfonamides. These compounds were confirmed by FT-IR and ¹H NMR spectroscopy. Moreover, the structure of the complex was studied by single-crystal X-ray diffraction method. The green crystal of Pd₂L₄ [L = N-(2-pyridyl) sulfonamide](1) was found to crystallize in the monoclinic space group C2/c with a = 18.2013(19), b = 19.7544(16), c = 17.2898(19) Å, β = 120.179(8) °; V = 5374.0(9) ų; Z = 4; the final R ₁ = 0.0894, wR ₂ = 0.1754 (or 5867 observed reflections and 318 variables). The Pd–Pd distance is 2.567(2) Å. In addition, PTS and Pd₂L₄ presented different antibacterial behaviors. The free ligand was active against Staphylococcus aureus and Escherichia coli, but the complex was inactive against them.     

A one-pot three-component reactions for the synthesis of fully substituted spiro indeno[1,2-b]quinoxaline derivatives

An efficient and simple approach of the synthesis of some spiro indeno[1,2-b]quinoxalines via a one-pot three-component reaction of 11H-indeno[1,2-b]quinoxalin-11-one, pyrazolone, and malononitrile in the presence of Na₂CO₃ at 70 °C is reported. This reaction has shown to have high atom economy.     

Determination of mercury(II) ions in seafood samples after extraction and preconcentration by a novel functionalized magnetic metal–organic framework nanocomposite

This work describes a novel functionalized magnetic metal–organic framework nanocomposite [(Fe₃O₄‐2,5‐dimercapto‐1,3,4‐thiadiazole)/metal–organic framework] and its application in the preconcentration of Hg(II) ions. The parameters affecting the preconcentration procedure were optimized by a Box–Behnken design through response surface methodology. Three variables (uptake time, magnetic nanosorbent amount, and pH value) were selected as the main factors affecting the sorption step, while four variables (type, volume, and concentration of the eluent; and elution time) were selected as main factors in the optimization study of the elution step. Following the sorption and elution of analytes, the ions were quantified by cold vapor atomic absorption spectrometry. Under the optimum conditions, the limit of detection was 0.01 ng/mL and all the relative standard deviations were less than 10%. The obtained sorption capacity (in mg/g) of this new sorbent was 124. Ultimately, this nanocomposite was successfully applied to the rapid extraction of trace quantities of Hg(II) ions in seafood samples and satisfactory results were obtained.     

Ionic liquid promoted one-pot synthesis of 3-aminoimidazo[1,2-a]pyridines

3-Aminoimidazo[1,2-a]pyridines have been synthesized in good to excellent yields in the presence of the ionic liquid 1-butyl-3-methylimidazolium bromide [bmim]Br, the reaction workup is simple and the ionic liquid can be easily separated from the product and reused.     

Nano-SiO2 catalyzed three-component preparations of pyrano[2,3-d]pyrimidines, 4H-chromenes,and dihydropyrano[3,2-c]chromenes

An efficient one-pot three-component procedure has been developed for the preparation of tetrahydrobenzo[b]pyrans, dihydropyrano[3,2-c]chromenes, and pyrano[2,3-d]pyrimidines using nano-SiO₂ as catalyst in H₂O at 70 °C. This methodology has a number of advantages such as: use of reusable catalyst, easy access, short reaction times, high yields, easy work up and use of non-toxic and green solvent.     

Transport properties of methane,ethane, propane, <Emphasis Type="Italic">iso</Emphasis>-butane and <Emphasis Type="Italic">neo</Emphasis>-pentane from ab initio potential energy surfaces

In this work, the potential energy surfaces for methane, ethane, propane, iso-butane and neo-pentane, obtained from the ab initio calculations via different levels of electron-correlation, were used in the framework of the kinetic theory to calculate the transport collision integrals and their corresponding low-density transport coefficients. The theoretical results are compared with the available experimental data and the effective scaling potential parameters of methane, ethane, propane, iso-butane and neo-pentane along with the kinetic theory collision integrals and higher order correction factors were obtained. Relation between different potentials and kinetic theory collision integrals are discussed and it was shown that the Mason–Monchick approach is a reliable approximation in the calculation of diffusion coefficients and shear viscosities of chain alkanes, whereas the full predictive Boltzmann weighting method is successful only for lighter alkanes, such as methane and ethane.     

An Efficient Route to Pyridazino[4, 3‐e][1, 3, 4]thiadiazines

Some new 3‐(alkylsulfanyl)‐7‐chloro‐1‐phenyl‐1H‐pyridazino [4,3‐e][1,3,4]thiadiazine were synthesized by treatment of the alkyl‐2‐phenylhydrazinecarbodithioates with 4‐bromo‐3,6‐dichloropyridazine in alkaline acetonitrile. Orientation of the reaction has been determined by X‐ray crystallography technique. The chlorine atom on the number 7 position of these products was replaced by secondary amines at reflux condition.     

Cellulose whiskers reinforced polyvinyl alcohol copolymers nanocomposites

Nanocomposite materials were prepared from copolymers of polyvinyl alcohol and polyvinyl acetate and a colloidal aqueous suspension of cellulose whiskers prepared from cotton linter. The degree of hydrolysis of the matrix was varied in order to vary the hydrophilic character of the polymer matrix and then the degree of interaction between the filler and the matrix. Nanocomposite films were conditioned at various moisture contents, and the dynamic mechanical and thermal properties were characterized using dynamic mechanical analysis and differential scanning calorimetry, respectively. Tensile tests were performed at room temperature to estimate mechanical properties of the films in the non linear range. All the results show that stronger filler/matrix interactions occur for fully hydrolyzed PVA compared to partially hydrolyzed samples. For moist samples, a water accumulation at the interface was evidenced. The reinforcing effect was found to be all the higher as the degree of hydrolysis of the matrix was high.