scholarly journals Modification of Pea Starch and Dextrin Polymers with Isocyanate Functional Groups

Polymers ◽  
2018 ◽  
Vol 10 (9) ◽  
pp. 939 ◽  
Author(s):  
Reza Hosseinpourpia ◽  
Arantzazu Echart ◽  
Stergios Adamopoulos ◽  
Nagore Gabilondo ◽  
Arantxa Eceiza
Keyword(s):  
Moisture Sorption ◽  
Analysis Data ◽  
Water Vapor Sorption ◽  
Molar Ratio ◽  
Elemental Analysis Data ◽  
Slight Reduction ◽  
Modified Starch ◽  
13C Nuclear Magnetic Resonance ◽  
High Molar Ratio ◽  
Pea Starch

Pea starch and dextrin polymers were modified through the unequal reactivity of isocyanate groups in isophorone diisocyanate (IPDI) monomer. The presence of both urethane and isocyanate functionalities in starch and dextrin after modification were confirmed by Fourier transform infrared spectroscopy (FTIR) and 13C nuclear magnetic resonance (13C NMR). The degree of substitution (DS) was calculated using elemental analysis data and showed higher DS values in modified dextrin than modified starch. The onsets of thermal degradation and temperatures at maximum mass losses were improved after modification of both starch and dextrin polymers compared to unmodified ones. Glass transition temperatures (Tg) of modified starch and dextrin were lower than unmodified control ones, and this was more pronounced in modified dextrin at a high molar ratio. Dynamic water vapor sorption of starch and dextrin polymers indicated a slight reduction in moisture sorption of modified starch, but considerably lower moisture sorption in modified dextrin as compared to that of unmodified ones.

scholarly journals INVESTIGATION AND OPTIMIZATION OF COMPLEXATION OF COBALT IONS WITH DIHYDROQUERCETIN IN AQUEOUS SOLUTIONS

2019 ◽  
pp. 95-104
Author(s):  
Елена (Elena) Владимировна (Vladimirovna) Столповская (Stolpovskaya) ◽  
Наталья (Natal'ya) Николаевна (Nikolaevna) Трофимова (Trofimova) ◽  
Василий (Vasiliy) Анатольевич (Anatol'evich) Бабкин (Babkin) ◽  
Роман (Roman) Георгиевич (Georgievich) Житов (Zhitov)
Keyword(s):  
Aqueous Solutions ◽  
Bound Water ◽  
Analysis Data ◽  
Molar Ratio ◽  
Elemental Analysis Data ◽  
Cobalt Ions ◽  
Ph Values ◽  
Reaction Solution ◽  
Form Compound

We continue to study the reactions of complexation of biogenic metal ions with flavonoid dihydroquercetin (DHQ). The interaction of Co2+ ions with DHQ in aqueous solutions has been studied. It is established that complexes with different stoichiometry are formed at different pH values of the solution. Changing the pH of the solution from 6.0 to 7.0 leads to the formation of compounds 1–3 with a metal: flavonoid ligand (Met: L) ratio from 1: 2 at pH 6.0 (1) via 2: 3 at pH 6.4 -6.7 (2) to 1: 1 at pH 6.8-7.0 (3). Using the method of thermogravimetry with elemental analysis data, the most probable composition of compounds was established with the determination of the amount of bound water: [CoL2(H2O)4] for 1, [Co2L3(OH)(H2O)4] for 2 and [CoL(OH)(H2O)2] for 3. The conditions for the complexation of Co2+ ions with dihydroquercetin in aqueous solutions to form compound 2, optimized for the yield of the product, are proposed. pH of the solution is 6.7, the reaction time is 15 minutes, the temperature of the reaction solution is 90 °C, molar ratio of the initial reagents DHQ:Co2+ is 1: 1.5, initial concentrations are 0,020 M DHQ and 0,030 M Co2+, the source of Co2+ is CoSO4∙7H2O. The yield of the product is 81.8 %.

Synthesis, Characterization and Thermal Degradation of Some New 3,5-dimethyl Pyrazole Derivatives

2017 ◽  
Vol 68 (2) ◽  
pp. 317-322
Author(s):  
Anca Mihaela Mocanu ◽  
Constantin Luca ◽  
Alina Costina Luca
Keyword(s):  
Thermal Degradation ◽  
Degradation Mechanism ◽  
New Products ◽  
Analysis Data ◽  
Biological Properties ◽  
Elemental Analysis Data ◽  
Ftir Analysis ◽  
Spectral Measurements ◽  
Chemical Structures ◽  
And Storage

The purpose of this research is to synthetize, characterize and thermal degradation of new heterolytic derivates with potential biological properties. The derivates synthesis was done by obtaining new molecules with pyralozone structure which combine two pharmacophore entities: the amidosulfonyl-R1,R2 phenoxyacetil with the 3,5-dimethyl pyrazole which can have potential biological properties. The synthesis stages of the new products are presented as well as the elemental analysis data and IR, 1H-NMR spectral measurements made for elucidating the chemical structures and thermostability study which makes evident the temperature range proper for their use and storage. The obtained results were indicative of a good correlation of the structure with the thermal stability as estimated by means of the initial degradation temperatures as well as with the degradation mechanism by means of the TG-FTIR analysis.

Synthesis, Antimalarial Evaluation and SAR Study of Some 1,3,5-Trisubstituted Pyrazoline Derivatives

2019 ◽  
Vol 16 (10) ◽  
pp. 807-817 ◽  
Author(s):  
Shilpy Aggarwal ◽  
Deepika Paliwal ◽  
Dhirender Kaushik ◽  
Girish Kumar Gupta ◽  
Ajay Kumar
Keyword(s):  
Antimalarial Activity ◽  
Analysis Data ◽  
Docking Study ◽  
Maximum Activity ◽  
Elemental Analysis Data ◽  
Mass Spectral ◽  
Structure Activity ◽  
Pharmacokinetic Properties ◽  
Sar Study

The synthesis of a novel series of 1,3,5-trisubstitiuted pyrazoline was achieved by refluxing chalcone derivative with different heteroaryl hydrazines. The newly synthesized compounds were characterized by 1H NMR, 13CNMR, mass spectral and elemental analysis data. The synthetic series of novel pyrazoline hybrids was screened for in vitro schizont maturation assay against chloroquine sensitive 3D7 strain of Plasmodium falciparum. Most of the compounds showed promising in vitro antimalarial activity against CQ sensitive strain. The preliminary structure-activity relationship study showed that quinoline substituted analog at position N-1 showed maximum activity followed by benzothiazole substitution, while phenyl substitution lowers the antimalarial activity. The observed activity was persistent by the docking study on P. falciparum cystein protease falcipain-2. The pharmacokinetic properties were also studied using ADME prediction.

Electrical Conductivity of Chloro(phenyl)glyoxime and Its Co(II), Ni(II) and Cu(II) Complexes

2003 ◽  
Vol 68 (7) ◽  
pp. 1233-1242 ◽  
Author(s):  
Orhan Turkoglu ◽  
Mustafa Soylak ◽  
Ibrahim Belenli
Keyword(s):  
Electrical Conductivity ◽  
Temperature Dependence ◽  
Electric Conductivity ◽  
Crystal Structures ◽  
Elemental Analysis ◽  
Analysis Data ◽  
Elemental Analysis Data ◽  
The Stability ◽  
Xrd Patterns ◽  
Metal Ligand

Chloro(phenyl)glyoxime, a vicinal dioxime, and its Ni(II), Cu(II) and Co(II) complexes were prepared. XRD patterns of the complexes point to similar crystal structures. IR and elemental analysis data revealed the 1:2 metal-ligand ratio in the complexes. The Co(II) complex is a dihydrate. Temperature dependence of electrical conductivity of the solid ligand and its complexes was measured in the temperature range 25-250 °C; it ranged between 10-14-10-6 Ω-1 cm-1 and increased with rising temperature. The activation energies were between 0.61-0.80 eV. The Co(II) complex has lower electric conductivity than the Ni(II) and Cu(II) complexes. This difference in the conductivity has been attributed to differences in the stability of the complexes.

scholarly journals The synthesis and characterization of some new diazoamino derivatives

2010 ◽  
Vol 16 (1) ◽  
pp. 89-95
Author(s):  
Mihaela Mocanu
Keyword(s):  
1H Nmr ◽  
Bioactive Compounds ◽  
Elemental Analysis ◽  
Analysis Data ◽  
Biological Properties ◽  
Synthesis And Characterization ◽  
Elemental Analysis Data ◽  
Spectral Measurements ◽  
Inflammatory Processes

The sulfonamidic moiety is much encountered in structures of bioactive compounds. In the present paper the studies on the sulfonamidated aryloxyalkylcarboxylic acids are extended by their attaching on certain substrata able to confer some special biological properties to the final products, such as anti-tumor and antioxidant actions useful in treating inflammatory processes, ulcer, convulsions and diabetes, as well as a herbicidal action. The stepwise syntheses of the sulfonamidated aryloxyalkylcarboxylic acid derivatives and their characterization by elemental analysis data and IR, 1H-NMR and UV-Vis spectral measurements are described. The newly obtained compounds could show potential pharmaceutical and herbicide properties.

Synthesis and anticancer evaluation of some coumarin and azacoumarin derivatives

2021 ◽  
Vol 23 (2) ◽  
pp. 27-34
Author(s):  
Safyah B. Bakare
Keyword(s):  
Carboxylic Acid ◽  
Elemental Analysis ◽  
Biological System ◽  
Analysis Data ◽  
Elemental Analysis Data ◽  
Coumarin Derivatives ◽  
Anti Cancer ◽  
Analgesic Agents ◽  
Mcf 7

Abstract Coumarin and its nitrogen analogue 1-aza coumarin are a class of lactones and lactams, respectively, which are indispensable heterocyclic units to both chemists and biochemists. 1-Aza coumarin derivatives, which ultimately metabolize as the corresponding 8-hydroxy coumarins in the biological system are therefore found to be very good anti-inflammatory, anti-cancer, and analgesic agents. A series of hybrid substituted coumarin and azacoumarin-3-carboxylic acid derivatives (8-methoxycoumarin-3-carboxylic acid (4a), 8-methoxyazacoumarin-3-carboxylic acid (4b), 5-bromo-8-methoxycoumarin-3-carboxylic acid (5a), 5-bromo-8-methoxyazacoumarin-3-carboxylic acid (5b), 2-acetoxy-5-bromo-8-methoxyquinoline-3-carboxylic acid (6), and 5,7-di(phenylazo)-8-methoxycoumarin-3-carboxylic acid (7) were synthesized and structurally proved using spectral and elemental analysis data. Substituted coumarin-3-carboxylic acid (4a and 5a) and Substituted azacoumarin-3-carboxylic acid (4b, 5b and 6) were tested for their in vitro cytotoxic activity against MCF-7 and HepG-2 cell lines.

Сrystalline structure and dielectric properties of ceramic materials based on AgNbO3

2020 ◽  
Vol 63 (7) ◽  
pp. 75-78
Author(s):  
Polina A. Bezborodova ◽  
◽  
Elena M. Filonenko ◽  
Kseniya R. Erager ◽  
Anatoly V. Butakov ◽  
...  
Keyword(s):  
Rietveld Method ◽  
Average Particle Size ◽  
Ceramic Materials ◽  
Analysis Data ◽  
Molar Ratio ◽  
Average Particle ◽  
Dielectric Parameters ◽  
Low Frequencies ◽  
X Ray ◽  
Substitution Degree

Using the data of qualitative X-ray phase analysis, it was shown that in a wide concentration range at 1223 K compounds based on silver niobate are formed in the condition of the heterovalent substitution of tungsten(VI) ions for niobium(V) ions. These compounds are isomorphic to a perovskite-type structure. Microprobe analysis data allows to determine the homogeneity of the analyzed samples and the correspondence of their experimental compositions to the theoretical ones for the formula Ag1-xNb1-xWxO3. Using the data of X-ray diffraction analysis (Rietveld method) in the Crystallography Data Analysis Software – GSAS, the crystal structure of the obtained compounds was refined. The surface morphology of samples having been obtained at 1373 K was investigated by scanning electron microscopy (SEM). It was shown that with an increase of Nb5+ to W6+ substitution degree for Ag1-xNb1-xWxO3 ceramic samples in the range of the (0.2≤x≤0.8) molar ratio, the average particle size for the studied compositions grows from 1.3 to 5.2 μm, respectively. For the obtained ceramic compounds based on silver niobate with a perovskite-like structure (tetragonal distortion), the temperature-frequency dependences of dielectric parameters in the range 300-900 K were studied. It was found that samples slowly cooled from 1373 K are characterized by low values of (ε ~ 10) and loss (tgδ ~ 0.004 at f = 1 kHz) at room temperature. The ceramics obtained are characterized by relatively high values of dielectric permittivity ε at low frequencies and/or high temperatures. The dielectric parameters of the obtained ceramics are similar to the characteristics of so-called "colossal" dielectric constant materials. The revealed features of the dielectric characteristics of quenched ceramics apparently result from Maxwell-Wagner relaxation at intercrystalline contacts.

scholarly journals p15s (15-kD Antimicrobial Proteins) Are Stored in the Secondary Granules of Rabbit Granulocytes: Implications for Antibacterial Synergy With the Bactericidal/Permeability-Increasing Protein in Inflammatory Fluids

Blood ◽  
1997 ◽  
Vol 89 (2) ◽  
pp. 672-679 ◽  
Author(s):  
Kol Zarember ◽  
Peter Elsbach ◽  
Kwang Shin-Kim ◽  
Jerrold Weiss
Keyword(s):  
Bone Marrow ◽  
Bone Marrow Cells ◽  
Extracellular Fluid ◽  
Molar Ratio ◽  
Immunogold Electron Microscopy ◽  
Antimicrobial Proteins ◽  
High Molar Ratio ◽  
Rabbit Bone ◽  
Polymerase Chain ◽  
Primary Granules

Abstract The bactericidal potency toward complement-resistant Escherichia coli of bactericidal/permeability-increasing protein (BPI) released from polymorphonuclear leukocytes (PMNs) in glycogen-induced inflammatory peritoneal exudates of rabbits is dependent on synergy with extracellular p15s. This synergy depends on the high molar ratio of p15s to BPI in the extracellular fluid (∼50:1), which greatly exceeds the intracellular ratio (∼5:1). To explore the possible basis of the greater accumulation of p15s in inflammatory fluid, we examined the subcellular localization of BPI and p15 in PMNs. Immunogold electron microscopy confirmed the storage of BPI in primary granules and showed that p15s are stored in secondary granules. Reverse-transcription polymerase chain reaction of density-fractionated rabbit bone marrow cells verified that p15s are expressed later than BPI during myeloid differentiation. As the inflammatory response evolves, p15 mRNA appears earlier in blood and exudate cells than mRNA for BPI, consistent with release of progressively less mature precursors from bone marrow. Finally, Ca2+-ionophore–mediated exocytosis of p15s occurs more readily than release of BPI. We therefore propose that localization of a synergistic partner of BPI (p15s) in more readily released secondary granules allows the neutrophil to mobilize potent BPI-dependent antibacterial activity extracellularly without significant depletion of intracellular BPI stores.

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