N-p-Chlorophenyl-2-thenohydroxamic Acid a Sensitive Reagent for Spectrophotometric Determination of Vanadium

The solvent extraction and spectrophotometric determination of vanadium(V) with N-p-chlorophenyl-2-thenohydroxamic acid (CPTHA) is described. The absorption spectrum of the vanadium(V)- CPTHA extracts in chloroform, from 4 mol/dm3 hydrochloric acid has its absorbance maximum at 530 nm; the reagent being colourless does not absorb at this wavelength. The coloured system obeys Beer\u27s law over a wide range. The molar absorptivity in terms of vanadium is 5500 dm3 mo1-1 cm-1 at 530 nm. The optimum acid range for quantitative extraction of the chelate is 3 to 9 mol/dm3 hydrochloric acid. The method is free from the interference of iron(III) and several other alloying elements which are often associated with vanadium. The method has been successfully used for determination of vanadium in BCS steels

N-p-Chlorophenyl-2-thenohydroxamic Acid a Sensitive Reagent for Spectrophotometric Determination of Vanadium

The solvent extraction and spectrophotometric determination of vanadium(V) with N-p-chlorophenyl-2-thenohydroxamic acid (CPTHA) is described. The absorption spectrum of the vanadium(V)- CPTHA extracts in chloroform, from 4 mol/dm3 hydrochloric acid has its absorbance maximum at 530 nm; the reagent being colourless does not absorb at this wavelength. The coloured system obeys Beer\u27s law over a wide range. The molar absorptivity in terms of vanadium is 5500 dm3 mo1-1 cm-1 at 530 nm. The optimum acid range for quantitative extraction of the chelate is 3 to 9 mol/dm3 hydrochloric acid. The method is free from the interference of iron(III) and several other alloying elements which are often associated with vanadium. The method has been successfully used for determination of vanadium in BCS steels

EXPERIMENTAL AND COMPUTATIONAL STUDY OF BINDING INTERACTION OF ALKOXY DERIVATIVES OF N-ARYLHYDROXAMIC ACIDS WITH DNA

Objective: Binding affinity towards DNA for small molecules is very important in the development of new therapeutic reagents. Interaction between N-Arylhydroxamic acid derivatives N-p-Tolyl-4-Ethoxybenzohydroxamic acid (p-TEBHA) and N-o- Tolyl-4-Ethoxybenzohydroxamic Acid (o-TEBHA), with calf thymus DNA (CT DNA) were studied by UV–visible absorption, fluorescence,  viscosity measurement and molecular docking. Methods: The absorption and emission spectra of DMSO solution of hydroxamic acid derivatives were studied for their binding activity with calf-thymus DNA by titration with increasing amount hydroxamic acids. Docking was performed by HEX software. Results: Fluorescent spectra showed that CT DNA quenches the emission spectra of p-TEBHA & o-TEBHA with binding constant 1.6 Ñ… 108 M-1 and 4.3 Ñ… 103 M-1 respectively. Competitive study with ethidium bromide (EB) indicates that p-TEBHA can displace the DNA-bound EB suggesting strong competition with EB whereas o-TEBHA does not displace the DNA-bounded Ethidium bromide effectively. UV study of the interaction of the complexes with calf-thymus DNA has shown that the hydroxamic acid derivatives can bind with CT DNA. The docking studies were used to predict the mode of interaction of the drug with DNA. It was observed that as far as binding strength was concerned the computational results complemented the experimental results. Conclusion: Investigated hydroxamic acid derivatives are found to be strong DNA binders and seem to have promising drug like nature

Antiinflammatory Therapy with Canakinumab for Atherosclerotic Disease

Background: Experimental and clinical data suggest that reducing inflammation without affecting lipid levels may reduce the risk of cardiovascular disease. Yet, the inflammatory hypothesis of atherothrombosis has remained unproved. Methods: We conducted a randomized, double-blind trial of canakinumab, a therapeutic monoclonal antibody targeting interleukin-1β, involving 10,061 patients with previous myocardial infarction and a high-sensitivity C-reactive protein level of 2 mg or more per liter. The trial compared three doses of canakinumab (50 mg, 150 mg, and 300 mg, administered subcutaneously every 3 months) with placebo. The primary efficacy end point was nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death. RESULTS: At 48 months, the median reduction from baseline in the high-sensitivity C-reactive protein level was 26 percentage points greater in the group that received the 50-mg dose of canakinumab, 37 percentage points greater in the 150-mg group, and 41 percentage points greater in the 300-mg group than in the placebo group. Canakinumab did not reduce lipid levels from baseline. At a median follow-up of 3.7 years, the incidence rate for the primary end point was 4.50 events per 100 person-years in the placebo group, 4.11 events per 100 person-years in the 50-mg group, 3.86 events per 100 person-years in the 150-mg group, and 3.90 events per 100 person-years in the 300-mg group. The hazard ratios as compared with placebo were as follows: in the 50-mg group, 0.93 (95% confidence interval [CI], 0.80 to 1.07; P = 0.30); in the 150-mg group, 0.85 (95% CI, 0.74 to 0.98; P = 0.021); and in the 300-mg group, 0.86 (95% CI, 0.75 to 0.99; P = 0.031). The 150-mg dose, but not the other doses, met the prespecified multiplicity-adjusted threshold for statistical significance for the primary end point and the secondary end point that additionally included hospitalization for unstable angina that led to urgent revascularization (hazard ratio vs. placebo, 0.83; 95% CI, 0.73 to 0.95; P = 0.005). Canakinumab was associated with a higher incidence of fatal infection than was placebo. There was no significant difference in all-cause mortality (hazard ratio for all canakinumab doses vs. placebo, 0.94; 95% CI, 0.83 to 1.06; P = 0.31). Conclusions: Antiinflammatory therapy targeting the interleukin-1β innate immunity pathway with canakinumab at a dose of 150 mg every 3 months led to a significantly lower rate of recurrent cardiovascular events than placebo, independent of lipid-level lowering. (Funded by Novartis; CANTOS ClinicalTrials.gov number, NCT01327846.

Determination of various physical ammeters of metal extractants

442-444Various physical parameters like densities, solubilities in water and various organic solvents, distribution ratios between aqueous and different immiscible organic solvents and solubility parameters of the versatile metal extracts, the hydroxamic acids are presented in this paper. The distribution constants can be correlated satisfactorily' with theoretical calculations based on regular solution theory. Density and solubility data help in determining the solubility parameters of these metal extractants various organic solvents

<b>Activation parameters and excess thermodyanamic functions of hydroxamic acids in acetone-water mixture at 303.15 K and 313.15 K: A viscometric approach</b>

Experimental values of density and viscosity of N-arylsubstituted hydroxamic acids were evaluated at T = 303.15 K and 313.15 K in acetone-water mixture as a function of their concentration. The properties of solutes were obtained as an intercept of plots C vs η of solutions. Applying these data, viscosity-B-coefficients, activation parameters (Δμ10≠) and (Δμ20≠) and excess thermodynamic functions, viz., excess molar volume (VE), excess viscosity, ηE and excess molar free energy of activation of flow, (GE) were calculated. The value of interaction parameter, d, of Grunberg and Nissan expression have also been calculated and reported. Analysis of these data suggests that specific interactions are present in the system

Strength of weak bases in aqueous acid by solvent extraction method

197-200<span style="font-size:12.0pt;font-family: " times="" new="" roman";mso-fareast-font-family:"times="" roman";mso-ansi-language:="" en-in;mso-fareast-language:en-in;mso-bidi-language:ar-sa"="" lang="EN-IN">The protonation behaviour of N-arylsubstituted hydro xamic acids is investigated by the determination of their ionisation ratio measurements following the solvent extraction method. These reagents act as weak organic bases in strong acidic solutions. The values of protonation constants of the conjugate acids of these reagents are determined using three classical procedures, in order to rationalise the differences observed between <i style="mso-bidi-font-style: normal">pKBH+ values estimated by these methods. The first is based on the Bunnett-Olsen free energy relationship, developed for acid solutions and uses an ac idity function. The other is known as Excess Acidity Method. or X-function method . This method uses overlapping indicators but does not involve acidity function. The values of <i style="mso-bidi-font-style: normal">pKBH+ obtained by these two extrapolative procedures, both of which involve the use of activity coefficient ratios have been compared with the acidity constants obtained by old classical procedure, the Hammett Acidity Function Method.</span

Fluorescence and docking studies on the binding of copper and cobalt complexes to DNA and RNA

<p>Nucleic acid are involved in fundamental biological functions as propagation of the genetic material, storage of genetic information and enzymatic activity. A high-throughput screen is necessary to identify compounds that bind to the target with high affinity, for developing new drugs that target with high affinity, for developing new drugs that target the DNA/RNA. Hydroxamic acids, the drug like molecules show both HBD and HBA capability.</p