Synthesis of pharmacologically active hydrogels based on combined silicon and titanium polyolates

The target synthesis of new biologically active hydrogels based on combined silicon and titanium polyolates was carried out. The optimum conditions for hydrogel formation and their composition were determined. The type of hydrogels and mechanisms of gelation depend on the nature of polyols: gels based on combined silicon and titanium polyethylene glycolates are polymeric and formed via the polycondensation mechanism, whereas gels based on combined silicon and titanium glycerolates are colloidal and formed via the coagulation-condensation mechanism. The combined hydrogels based on silicon dimethyl glycerolates and titanium tetraglycerolate exhibit enhanced transcutaneous, wound healing, and regenerating activity.     

Reactivity features of polychlorobiphenyl congeners in the nucleophilic substitution reactions

Groups of congeners and individual congeners of polychlorobiphenyls contributing to the composition of the technical mixture “Sovol” (PCB 60, PCB 64, PCB 70, PCB 74, PCB 97, PCB 101, PCB 105, PCB 110, PCB 118, PCB 138, PCB 149, PCB 156, and PCB 163) were synthesized by the reaction of aryl-aryl coupling. The interaction of the congeners with sodium methoxide was performed and their complete conversion was proved. By means of gas chromatography-mass spectrometry the PCBs methoxy derivatives were identified. The data on the reactivity of the individual polychlorobiphenyl congeners were precised.     

Equations of the shallow water model on a rotating attracting sphere. 1. Derivation and general properties

A shallow water model on a rotating attracting sphere is proposed to describe large-scale motions of the gas in planetary atmospheres and of the liquid in the world ocean. The equations of the model coincide with the equations of gas-dynamic of a polytropic gas in the case of spherical gas motions on the surface of a rotating sphere. The range of applicability of the model is discussed, and the conservation of potential vorticity along the trajectories is proved. The equations of stationary shallow water motions are presented in the form of Bernoulli and potential vorticity integrals, which relate the liquid depth to the stream function. The simplest stationary solutions that describe the equilibrium state differing from the spherically symmetric state and the zonal flows along the parallels are found. It is demonstrated that the stationary equations of the model admit the infinitely dimensional Lie group of equivalence. __________ Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 50, No. 2, pp. 24–36, March–April, 2009.     

Reaction of Internal Fluoroolefin Oxides with Camphor Thiosemicarbazone

Epoxy derivatives of internal fluoroolefins (both cis and trans isomers) react in a stereospecific manner with (1S)- or rac-camphor thiosemicarbazone in a polar aprotic medium to give the corresponding 5-fluoro-4-hydroxy-4,5-bis(polyfluoroalkyl)thiazol-2-ylhydrazones. From unsymmetrical 2,3-epoxydodecafluorohexane a mixture of regioisomeric hydrazones is formed. According to the ¹H and ^{1 9}F NMR data, the resulting trans-hydrazones in (CD₃)₂SO and CDCl₃ exist as mixtures of diastereoisomers occurring in a dynamic equilibrium.     

First Example of the Synthesis of Di(fluoroalkyl)-substituted Pyrimidines

4,5-Bis(hydroxy)-4-trifluoromethyl-6-(fluoroalkyl)hexahydropyrimidin-2-ones (thiones) have been obtained for the first time by the reaction of ureas (thioureas) with di(fluoroalkyl)-substituted 1,3-diketones and tetraols, the dehydration of which gave 2-hydroxy(mercapto)-4-trifluoromethyl-6-(fluoroalkyl)pyrimidines.     

Substitution of Cyano Group in Position 5 of 1,2,4-Triazines by Carboxylic Acid Hydrazide Residues under Solvent-Free Conditions

Russian Journal of Organic Chemistry - The possibility of substitution of the 5-cyano group in 1,2,4-triazines by carbohydrazide residues under solvent-free conditions with high yields has been...     

One-Pot Preparation Method of 5-Alkyl-3-(benzo)pyridyl-1,2,4-triazines

Russian Journal of Organic Chemistry - Convenient one-pot method was developed for the preparation of 5-alkyl-3-(2-pyridyl)-, 5-alkyl-3-(4-pyridyl)- or 5-alkyl-3-(quinolin-2-yl)-1,2,4-triazines in...