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The accessible D-ribose mercaptoacetyl-, 3-mercaptopropionyl-, and 2-mercaprobenzoylhydrazones were used to develop a method of synthesis of gold glyconanoparticles with the average particle diameter of 10–40 nm and a low polydispersity index.

A method of synthesis of 3-thiopropinyl derivatives of 5-oxo-1,3,4-benzothiadiazepine-4-acetic acid, potential antihypertensive drugs, vasopeptidase inhibitors, starting from 2-thiobenzoic acid hydrazide has been elaborated.

Basing on natural amino acid L-cysteine, commercially available aliphatic aldehydes, 2-acetylsulfanylbenzoyl chloride and 2,2′-disulfandiyldibenzoyl dichloride a synthesis was developed of (2R,4R)-2-alkyl-3-(2-mercaptobenzoyl)thiazolidine-4-carboxylic acids, potential antihypertensive compounds, inhibitors of angiotensin transforming enzyme.

Optically pure (2S,4S)-2-alkyl-6-oxo-3-(phenylcarbamothioyl)hexahydropyrimidine-4-carboxylic acids have been synthesized from natural L-asparagine, commercially available aldehydes, and phenyl isothiocyanate. The product structure was confirmed by 1H and 13C NMR data.

The natural amino acid L-cysteine, commercially available aldehydes, and 3-(acetylsulfanyl)propionyl chloride were used for the synthesis of 2-substituted (2R,4R)-3-(3-mercaptopropionyl)thiazolidine-4-carboxylic acids, potential antihypertensive drugs with angiotensin converting enzyme inhibiting action.

Proceeding from natural amino acid L-asparagine and commercially available aldehydes a stereoselective synthesis was developed of (2S,4S)-2-alkyl(aryl)-3-(3-sulfanylpropanoyl)-6-oxohydropyrimidine-4-carboxylic acids, potential antihypertensive drugs, inhibitors of the angiotensin converting enzyme.

A stereoselective three-step synthesis of the title thiazolidine-4-carboxylic acids (III), potential lead compounds for the development of antihypertensive drugs with angiotensin converting enzyme inhibitory activity, starting from natural L-cysteine (I) is given.

The peculiarities of zone migration and band broadening in the reversed-phase gradient HPLC of proteins were investigated. In the isocratic mode a critical composition of the mobile phase was found at which all proteins regardless of their molecular mass migrate with equal velocity and have a capacity factor equal to the phase ratio (VP/V0), i.e., the same capacity factor as a marker of total accessible volume would have in steric exclusion chromatography. It is shown that steric exclusion conditions are never achieved in gradient HPLC. In the first (adsorption stage) of gradient elution where the separation takes place the velocity of a protein increases until it becomes equal to the velocity of the desorbing solvent front at a critical distance X0 from column entrance. Strong broadening is characteristic of this stage. In the second (critical) stage the protein travels the remaining distance (L-X0) with the velocity of the solvent. A definition of X0 is given allowing one very simple calculation of the minimum permissible column length as a function of gradient steepness, mobile phase velocity and protein adsorption parameter. When x = X0 the protein zone has the smallest dispersion. Making L < X0 is especially disadvantageous, as it leads to anomalous bandspreading. The theory of gradient HPLC was refined on this basis and the usefulness of this approach in high-performance membrane chromatography is demonstrated.

A microchromatographic procedure for highly sensitive analysis of proteins has been developed by using short capillary columns with reverse-phase, ion-exchange, and hydrophobic interaction sorbents