The reaction of benzil with methyl alkyl ketones gave three isomeric cyclopentenone derivatives, 2-substituted and cis- and trans-5-substituted 4-hydroxy-3,4-diphenylcyclopent-2-en-1-ones. cis- and trans-2,5-Disubstituted 4-hydroxy-3,4-diphenylcyclopent-2-en-1-ones were formed in analogous reaction of benzil with dialkyl ketones. The structure of the products was confirmed by (1)H NMR spectroscopy and molecular-mechanics calculations.

A number of new inhibitors of plasmepsin II (PlmII) Plasmodium falciparum , which was one of the key factors of survival of malarial parasite, was synthesized. The inhibitors were analogues of pepstatin with different substitutions for the alanine residue. Effects of the inhibitors on human PlmII and cathepsin D were studied. Inhibition of PlmII by the substrate was found. This discovery required modification of the Henderson method for determination of inhibition constants. Two synthesized inhibitors were shown to exhibit a pronounced selectivity to PlmII ( K i = 5.5 and 5 nM) in comparison with that of cathepsin D ( K i = 230 and 3000 nM, respectively).

A new beta-diketone, 1,3-di(2-thienyl)-1,3-propanedione (HDTM), and the europium complexes [Eu(DTM)(3)Q] (Q is 1,10-phenanthroline (Phen), 4,7-diphenyl-1,10-phenanthroline (Bath)) have been synthesized. The luminescence characteristics and thermal stabilities of the these complexes and analogous europium complexes with 1,3-diphenyl-1,3-propanedione (HDBM) and 1,3-di(2-furanoyl)-1,3-propanedione (HDFM) have been compared. The relative luminescence intensity of the complexes increases in going from HDBM through HDFM to HDTM and in changing from Phen to Bath.

A new simple method of synthesis of heteroligand complexes [Ln(Dalkdtc) 3 Phen] (Ln = Eu or Er; Dalkdtc is the dialkyldithiocarbamate ion, Phen is o -phenanthroline) in an aqueous solution is described; the possibility of using the complexes as initial reagents for the synthesis of rare-earth sulfides is shown.

The type of mass transfer in the sorption of 4-nitrobenzaldehyde N , N -dimethylhydrazone (BDH) on silica chemically modified with hexadecyl groups was determined using the linear model of sorption dynamics, and distribution and mass transfer coefficients of hydrazone were calculated. Optimal conditions of the dynamic sorption preconcentration and desorption of BDH and its subsequent determination by reversed-phase high-performance liquid chromatography were proposed. The detection limit of the compound for preconcentration from a sample of 100 mL was 1 μg/L.

The simultaneous determination of preparations used for multicomponent intravenous anesthesia (Promedol, tramadol, ketamine, diazepam, Thiopental, and phentanyl) and of their metabolites in blood and urine of surgical patients by chromatography-mass spectrometry was considered. Artifacts due to the Chromatographie interference of various preparations and their metabolites were revealed. The lability of the anesthetics and their metabolites in the course of sample preparation and analysis by gas chromatography (GC) was examined. The degradation products of the test preparations responsible for the generation of false positive results were found. Phentanyl, Promedol, ketamine, tramadol, Thiopental, diazepam, and their metabolites excreted with urine in the free forms were determined in the whole blood and urine of surgical patients. Bound forms of metabolites and the initial medicinal preparations excreted as complexes with glucuronic acid and other acids were also determined in urine. Metabolites and impurity substances in the intravenous anesthetics with similar mass spectra and retention times were distinguished. Methodological recommendations concerning the analysis of difficult-to-separate (by capillary gas chromatography) pairs of substances used for intravenous anesthesia and their metabolites are given. The following pairs of components are difficult to separate: Norpromedol-2-methylamino-5-chlorobenzophenon (a product of diazepam hydrolysis), norketamine-Promedol, and anhydrotramadol (a GC artifact)-ketamine. The cumulation of an impurity substance from the tramadol preparation, identified by us as epoxytramadol, in the body was examined.

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The reasons for the acceleration of the oxidation of organic substances with acids under microwave irradiation are considered. The dynamic method (under conditions of continuously increasing temperature) was used for determining the apparent activation energy (E-a). The values of E-a for the oxidation of a number of organic compounds of different classes were calculated from experimental data using the Arrhenius equation, Equal values E-a obtained for amino acid oxidation under conditions of ordinary and microwave heating are indicative of identity of oxidation mechanisms. The changes of the kinetic characteristics in the second case are probably determined by the frequency and effectiveness of collisions of interacting particles; this effect is directly associated with the action of microwave radiation. It was found that the conditions required for decomposing organic matrices can be predicted from the data on decomposition conditions for individual model compounds.

Toxic ethylene and diethylene glycols, and also ethylene glycol dimethyl ether, ethylene glycol monoethyl ether, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,2-propanediol, 1,3-propanediol, 2-methyl-2,4-pentanediol, and glycerol were determined in alcoholic beverages and potable water by gas chromatography and chromatography-mass spectrometry simultaneously with other components of alcoholic beverages (higher alcohols, ethers, aldehydes, ketones, and volatile fatty acids). It was demonstrated that the chromatographic profile of glycols can serve as the identification criterion for the authentication of alcoholic beverages. The analyses were performed using HPFFAP open tubular columns with a length of 5 and 25 m and an inner diameter of 0.32 mm. Before the analysis, samples of wine were treated with activated carbon to remove high-molecular components. The detection limit of ethylene glycol and diethylene glycol in potable water after sample preconcentration by evaporation in a nitrogen flow is 0.2 mg/L.