Benzyloxyarylaliphatic acids: Synthesis and quantitative relations between structure and antiinflammatory activity

1982 ◽  
Vol 47 (9) ◽  
pp. 2514-2524 ◽  
Author(s):  
Miroslav Kuchař ◽  
Václav Rejholec ◽  
Bohumila Brunová ◽  
Jaroslava Grimová ◽  
Oluše Matoušová ◽  
...  
Keyword(s):  
Regression Analysis ◽  
Aromatic Ring ◽  
Erythrocyte Membrane ◽  
Antiinflammatory Activity ◽  
Structural Parameters ◽  
Antiinflammatory Effect ◽  
Physico Chemical

The paper describes synthesis of substituted benzyloxyarylaliphatic acids, I-V, and their efficacy in stabilization the erythrocyte membrane against hypotonic haemolysis and their antiinflammatory effect in inhibition of the kaolin oedema. The quantitative relations between these efficacies and the physico-chemical and structural parameters of the acids have been analysed. The two activities depend on the overall lipophilicity and acidity of the acids. In the investigated range of lipophilicity the dependence of the antiinflammatory effect on lipophilicity had a parabolic course, whereas in stabilization of the erythrocyte membrane this dependence was linear. In either case the efficacy was suppressed by extending the connecting chain between the carboxyl and the aromatic ring. Regression analysis suggests that in the group of benzyloxyarylaliphatic acids it is not possible to prepare compounds more effective than 3-chloro-4-benzyloxyphenylacetic acid (benzofenac, Ia) and its 2-methyl analogue IIa.

Quantitative relations between structure and antiinflammatory activity of aryloxoalkanoic acids

1988 ◽  
Vol 53 (8) ◽  
pp. 1862-1872 ◽  
Author(s):  
Miroslav Kuchař ◽  
Eva Maturová ◽  
Bohumila Brunová ◽  
Jaroslava Grimová ◽  
Hana Tomková ◽  
...  
Keyword(s):  
Regression Analysis ◽  
Structural Changes ◽  
Antiinflammatory Activity ◽  
Structural Parameters ◽  
Considerable Effect ◽  
Antiinflammatory Effect ◽  
Prolonged Action ◽  
Preclinical Development ◽  
Indicator Variables ◽  
Inhibitory Activities

The antiinflammatory effect of a series of aryloxoalkanoic acids II and of their biphenyl derivatives III was examined by measuring the inhibition of the development of carageenan- and adjuvant-induced edemas. The quantitative relations between the antiinflammatory effect and physicochemical and structural parameters of the compounds tested were evaluated. The equations obtained by the method of regression analysis showed a significant linear dependence of both inhibitory activities on the lipophilicity of the compounds and a considerable effect of some structural changes as expressed by indicator variables. The antiinflammatory effect is especially enhanced in both tests by the presence of a cyclic substituent at the aromatic ring. The high antiinflammatory effect of biphenylyl derivatives III is paralleled by their prolonged action. The prolongation of the effect is most likely a result of a suitable biotransformation of acid III to an efficient metabolite. The structural requirements which resulted from both the regression analysis and from the hypothesis of biotransformation of acids III were utilized in the synthesis of suitably substituted biphenylyloxoalkanoic acids. By this approach derivatives IIIe-i were obtained some of which showed a high antiinflammatory and also protracted effect. 4-(2',4'-Difluorbiphenylyl)-4-oxo-2-methylbutanoic acid (VÚFB-16 066, Flobufen) was chosen for further preclinical development.

The effects of lipophilicity on the inhibition of denaturation of serum albumin and on the activation of fibrinolysis observed with a series of benzyloxyarylaliphatic acids

1983 ◽  
Vol 48 (4) ◽  
pp. 1077-1088 ◽  
Author(s):  
Miroslav Kuchař ◽  
Václav Rejholec ◽  
Zdeněk Roubal ◽  
Oluše Matoušová
Keyword(s):  
Experimental Data ◽  
Regression Analysis ◽  
Serum Albumin ◽  
Biological System ◽  
Antiinflammatory Activity ◽  
Chemical Parameters ◽  
Membrane Stabilization ◽  
Physico Chemical ◽  
Experimental Values

Activation of fibrinolysis and inhibition of denaturation of serum albumin by a series of substituted benzyloxyarylaliphatic acids have been measured and analyzed in relation to the physico-chemical parameters of these acids. The lipophilicity of the benzyloxy derivatives was characterized both by the tabulated parameters π and by experimental data obtained by TLC. Regression analysis has revealed that the derivatives manifest higher lipophilicities in both the activation of fibrinolysis and the inhibition of denaturation, and that these lipophilicities are better described by the tabulated data than by experimental values. Taking into account the earlier results of regression analysis of erythrocyte membrane stabilization and antiinflammatory activity it can be judged that the role of lipophilicities of these substances is influenced by the nature of their interaction with the biological system.

Nucleophilicity and its parametrization

1989 ◽  
Vol 54 (1) ◽  
pp. 117-135
Author(s):  
Oldřich Pytela ◽  
Vítězslav Zima
Keyword(s):  
Regression Analysis ◽  
Linear Correlation ◽  
Correlation Equation ◽  
Chemical Processes ◽  
General Tendency ◽  
Orbital Interaction ◽  
Physico Chemical ◽  
Physical And Chemical ◽  
Two Parameter ◽  
Better Than

The method of conjugate deviations based on the regression analysis has been suggested for construction of a new nucleophilicity scale. This method has been applied to a set of 28 nucleophiles participating in 47 physical and chemical processes described in literature. The two-parameter nucleophilicity scale obtained represents-in the parameter denoted as ND-the general tendency to form a bond to an electrophile predominantly on the basis of the orbital interaction and-in the parameter denoted as PD-the ability to interact with a centre similar to the proton (basicity). The linear correlation equation involving the ND, PD parameters and the charge appears to be distinctly better than the most significant relations used. The correlation dependences have the physico-chemical meaning. From the position of individual nucleophiles in the space of the ND and PD parameters, some general conclusions have been derived about the factors governing the reactivity of nucleophiles.

scholarly journals Monoclinic and Orthorhombic NaMnO2 for Secondary Batteries: A Comparative Study

Energies ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1230
Author(s):  
Jessica Manzi ◽  
Annalisa Paolone ◽  
Oriele Palumbo ◽  
Domenico Corona ◽  
Arianna Massaro ◽  
...  
Keyword(s):  
Structural Parameters ◽  
Reversible Capacity ◽  
Beta Phase ◽  
X Ray Diffraction ◽  
Positive Electrodes ◽  
Detailed Structural Analysis ◽  
Physico Chemical ◽  
Sodium Batteries ◽  
The Impact ◽  
First Time

In this manuscript, we report a detailed physico-chemical comparison between the α- and β-polymorphs of the NaMnO2 compound, a promising material for application in positive electrodes for secondary aprotic sodium batteries. In particular, the structure and vibrational properties, as well as electrochemical performance in sodium batteries, are compared to highlight differences and similarities. We exploit both laboratory techniques (Raman spectroscopy, electrochemical methods) and synchrotron radiation experiments (Fast-Fourier Transform Infrared spectroscopy, and X-ray diffraction). Notably the vibrational spectra of these phases are here reported for the first time in the literature as well as the detailed structural analysis from diffraction data. DFT+U calculations predict both phases to have similar electronic features, with structural parameters consistent with the experimental counterparts. The experimental evidence of antisite defects in the beta-phase between sodium and manganese ions is noticeable. Both polymorphs have been also tested in aprotic batteries by comparing the impact of different liquid electrolytes on the ability to de-intercalated/intercalate sodium ions. Overall, the monoclinic α-NaMnO2 shows larger reversible capacity exceeding 175 mAhg−1 at 10 mAg−1.

Understanding of Lithium Insertion into λ-MnO2 Compounds

1998 ◽  
Vol 548 ◽  
Author(s):  
S. Sarciaux ◽  
A. Le Gal La Salle ◽  
A. Verbaere ◽  
Y Piffard ◽  
D. Guyomard
Keyword(s):  
Oxygen Content ◽  
Structural Parameters ◽  
Reversible Capacity ◽  
Rechargeable Batteries ◽  
Structural Water ◽  
Synthesis Conditions ◽  
Starting Compound ◽  
Physico Chemical ◽  
New Compounds

ABSTRACTA large variety of EMD and HTMD samples with various oxygen and water contents and various structural parameters Pr and Mt has been prepared. We show that the physico-chemical and structural parameters of the λ-MnO2 compounds are related to the synthesis conditions. New compounds were obtained with unusual amounts of intergrowth and twinning defects.The Li insertion study focuses on a comprehensive investigation of the relationships between the material characteristics of the samples and their Li insertion behavior, and on the structural characterization of selected compounds after cycling. The oxygen content drastically affects the shape of the discharge curve after the first cycle and the total reversible capacity. The amount of structural water has an influence on the transformation kinetics of the starting phase. For optimized oxygen content (y= 2 in MnOY), the intrinsic reversible Li insertion capacity is maximum when the amount of microtwinning defects is minimum and when the structure is either mostly Ramsdellite or faulted Pyrolusite. Results show that, upon cycling, the λ-MnO2 structure seems to evoluate towards less Pyrolusite defects together with the apparition of new kinds of defects.This work shows that λ-MnO2, compounds could be good candidates for the cathode application of Li-metal rechargeable batteries, provided that the physico-chemical and structural parameters of the starting compound are well chosen.

scholarly journals Effects of Physico-Chemical Parameters on Actinomycetes Communities during Composting of Agricultural Waste

2019 ◽  
Vol 11 (8) ◽  
pp. 2229
Author(s):  
Yuanping Li ◽  
Yanrong Chen ◽  
Yaoning Chen ◽  
Yanxin Wu ◽  
Chun Zhang ◽  
...  
Keyword(s):  
Regression Analysis ◽  
Moisture Content ◽  
16S Rdna ◽  
Community Composition ◽  
Agricultural Waste ◽  
Chemical Parameters ◽  
16S Rdna Gene ◽  
Rdna Gene ◽  
Gene Abundance ◽  
Physico Chemical

The objective of this study was to investigate the influence of physico-chemical parameters on Actinomycetes communities and to prioritize those parameters that contributed to Actinomycetes community composition during the composting of agricultural waste. Denaturing gradient gel electrophoresis of polymerase chain reaction (PCR-DGGE) and redundancy analysis (RDA) were used to determine the relationships between those parameters and Actinomycetes community composition. Quantitative PCR (qPCR) and regression analysis were used to monitor the 16S rDNA copy numbers of Actinomycetes and to analyse the correlations between physico-chemical parameters and Actinomyces 16S rDNA gene abundance, respectively. The RDA results showed that moisture content, water soluble carbon (WSC) and pH (p < 0.05) made the main contributions to the temporal variations of Actinomycetes community composition. The output of the regression analysis indicated that moisture content (R2 = 0.407, p < 0.01) showed a negative linear relationship with the Actinomyces 16S rDNA gene abundance.

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