Hyperbranched polyester poly(3-diethylamino)propionates and their copper(<Emphasis Type="SmallCaps">ii</Emphasis>) complexes

Novel polydentate ligands were obtained from second and third generation hyperbranched polyesters containing terminal (3-diethylamino)propionate groups. Polynuclear Cu^II complexes with these ligands were synthesized. The degree of diethylamination of the polyesters increases when moving from the second to the third generation (from 56 to 81%). In polynuclear complexes, the ratios of Cu to hyperbranched ligand are 6 : 1 and 13 : 1 for second and third generation polyester polyamines, respectively. It was demonstrated using IR and ESR spectroscopy that each coordination polyhedron in the complexes is an isolated paramagnetic center of the formula CuN₂O₂Solv₂ (Solv = H₂O, DMSO).     

Synthesis of 2-(2-methyltetrazol-5-yl)-2,2-dinitroacetonitrile and its reaction with substituted nitrile N-oxides

A procedure of synthesis of 2-(2-methyltetrazol-5-yl)-2,2-dinitroacetonitrile has been developed and its reaction with substituted nitrile N-oxides has been investigated, proceeding by the mechanism of 1,3-dipolar cycloaddition and affording 2-methyl-5-[(1,2,4-oxadiazol-5-yl)(dinitro)methyl]-2H-tetrazoles. The latter react with KOH in ethanol forming the potassium salt of 2-methyltetrazol-5-yldinitromethane and substituted 5-hydroxy-1,2,4-oxadiazoles.     

Magnetic Resonance of Ferritin Crystalline Particles in Tumor Tissue

Lyophilized samples of human tumor tissue exposed and not exposed to radiation therapy were investigated by magnetic resonance spectroscopy. The measurements were taken in the temperature range of 4–280 K on an X-band electron paramagnetic resonance spectrometer. Two types of ferromagnetic resonance signals were detected. The first type signals (g _eff ≈ 2.1 ÷ 2.4) were detected in the spectra of 25% of the samples. The orientational dependence of these signals has been found. The temperature dependences of the first type signals were measured. Specific features were observed near the temperature of 125 K. They are evidently typical for the Verwey phase transition in magnetite. We suppose that the first type signals may belong to arrays or chains of ferritin particles with the crystal core in the form of magnetite. The temperature dependences of magnetic resonance characteristics of ferritin in tumors are differ from those of the same characteristics of ferritin in healthy tissue investigated before. In spectra of irradiated tumors, the second type signals at low fields were detected which may be due to aggregates of different iron particles in cell lysosomes.     

Reaction 5-(Arylmethylidene)-2,4,6-pyrimidine-2,4,6(1H,3H,5H)-triones with Arenecarbaldehyde Phenylhydrazones in the Presence of Sodium N-Chlorobenzenesulfonamide

Russian Journal of Organic Chemistry - The reactions of 5-(arylmethylidene)-2,4,6-pyrimidine-2,4,6(1H,3H,5H)-triones with arenecarbaldehyde phenylhydrazones in the presence of sodium...     

Heterocyclization of 5-(Arylmethylidene)pyrimidine-2,4,6(1H,3H,5H)-triones with Arenecarbaldehyde Oximes in the Presence of N-Bromosuccinimide and Triethylamine

Russian Journal of Organic Chemistry - 5-(Arylmethylidene)pyrimidine-2,4,6(1H,3H,5H)-triones reacted with substituted benzaldehyde oximes in the presence of N-bromosuccinimide and triethylamine to...     

Three-component heterocyclization of 5-(arylmethylidene)pyrimidine-2,4,6(1<Emphasis Type="Italic">H</Emphasis>,3<Emphasis Type="Italic">H</Emphasis>,5<Emphasis Type="Italic">H</Emphasis>)-triones with aldehydes and amino acids

Previously unknown substituted 4-aryl-2,7,9-triazaspiro[4.5]decane-6,8,10-triones were synthesized in 50–70% yield by heating 5-(arylmethylidene)barbituric acids with N-methyl- or N-phenylglycine and para-formaldehyde or 4-methoxybenzaldehyde in boiling toluene for 14 h.