Objective. Total antioxidant capacity in serum is determined by the total mass of antioxidant substances and the antioxidant capacity per unit mass (average activity). The purpose of this study was to develop a method to determine the mass of antioxidant substances and average activity in human serum. Methods. Specimens of serum were collected from 100 subjects each from two different age group...

The quantitative determination of columbium based on reduction by amalgamated zin c and reox idation with potassium permanganate has, in general, produced results that lack both accuracy and precision. A study of t he various factors involved indicates that essential conditions requ ire adequate duration of reduction in t he presence of an excess of zinc and a proper concentration of both acid ...

The present paper describes a simple, selective and sensitive kinetic method for the determination of trace amounts of molybdenum(VI) based on its inhibitory effect on the reaction oxidation of 4-hydroxycoumarine by KMnO(4) in the presence of hydrochloric acid, at pH 1.75 at 25 degrees C. The rate of the indicator reaction was followed spectrophotometrically by measuring the decrease in the abs...

The typically planar amide when incorporated into bicyclic systems can undergo a significant distortion from planarity resulting in physical properties and reactivity that deviate from classical amide behaviour. Herein, we report a succinct protocol that utilises potassium permanganate to selectively α-oxygenate the benzylic position of ethano-Tröger's base derivatives to yield a new class of t...

A simple synthetic approach to racemic N-tert-butyloxycarbonyl-2-methyl-3-(1H-1,2,4-triazol-1-yl)alanine (5) in four steps and 68% overall yield starting from oxazoline derivative 1 is reported. This synthesis involves the alkylation of 1H-1,2,4-triazole with an O-tosyloxazoline derivative, followed by an oxazoline ring-opening reaction and oxidation of the N-protected β‑aminoalcohol by potassi...

A convenient approach for oxidation of structurally diverse alcohols has been developed using KMnO4 as oxidant agent in the presence of a catalytic amount of Al2O3 in aqueous acetonitrile. In this method various alcohols generally afforded the corresponding carbonyl compounds directly in good to high yield under ultrasound irradiation conditions. It shows that this kind of catalysis system is v...

The publications on Kjeldahl’s method for determining nitrogen that have appeared since Kjeldahl’s (1) original paper in 1883 perhaps outnumber those on any other analytical method in the same period of time.1 The diversity of papers is attributable to the immense usefulness of the method, to its need for modifications for applications to various types of organic and inorganic compounds, and to...

A new simple and sensitive kinetic spectrophotometric method for the determination of silymarin in pure form and in pharmaceutical formulations is described. The method is based on the oxidation of the drug with potassium permanganate at pH 7.0 +/- 0.2. The reaction is followed spectrophotometrically by measuring the decrease in the absorbance at 530 nm. The calibration graph is linear in the r...

The demonstration of the marked biological activity of oxybiotin (l-4), the oxygen analogue of biotin, has focused attention upon the mode of action of this compound. It became of particular interest to determine whether oxybiotin possesses intrinsic activity or whether its biological potency is due to its conversion into biotin. The evidence in the literature is conflicting on this point. Hofm...