Hydrogenated azolo- and azinopyridines based on 1,5-diketones

Compounds that contain a hydrogenated azolopyridine structure are formed in the reaction of various types of 1,5-diketones with ethanolamine, o-aminophenol, o-phenylenediamine, and aroylhydrazines; compounds that include a hydrogenated azinopyridine structure were obtained by the reaction of diketones with 3-aminopropanol and anthranilic acid. The hydrocyanation and oxidation of the compounds obtained were studied.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 240–245, February, 1979.     

Investigation of heterocyclic quinones XVII. Oxidative amination of 6-hydroxyquinazoline

Representatives of a new class of heterocyclic quinones — quinazoline-5,6-quinones — were obtained by the oxidative animation of 6-hydroxyquinazoline, 2-phenyl-6-hydroxyquinazoline, and 4-piperidino-6-hydroxyquinazoline. 6-Hydroxyquinazolines that are not substituted in the 2 position are animated in this position during oxidation. A possible mechanism for the amination is proposed.See [1] for communication XVI.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1698–1702, December. 1971.     

Quantum-chemical analysis of the reactivity of methanol dimers in their reaction with isocyanates

The CNDO/2 method has been used to investigate the reactivity of methanol dimers of various structures in nucleophilic addition reactions at the N=C bond of isocyanates. It is shown that effect of dimerization on the reactivity of the alcohol is in the same direction as the effect of an electron donating catalyst on the monomer, depending on the structure of the dimer and, in some instances, also on the conformation of the isocyanate.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 26, No. 3, pp. 345–348, May–June, 1990.     

Working conditions of a Clark-type sensor with a polyethylene membrane in the presence of vapours of chlorine derivatives of methane

The indications of a Clark-type electrochemical sensor with a polyethylene foil used as a membrane are noticeably changed if vapours of chlorine derivatives of methane (CCl₄, CHCl₃, CH₂Cl₂) are present in the atmosphere examined and the sensor has been calibrated in an atmosphere from which those vapours were absent. The sensitivity of the sensor increases and tends to deviate from linearity. The increase is more profound, when the number of chlorine atoms within a molecule of the vapour increases, the partial pressure of the vapour increases and the temperature of the atmosphere examined decreases. If the vapours affect the membrane for a long time, the response time decreases. If the membrane is freshly subjected to the influence of the vapours, a longer period of time is needed to reach a stable indication corresponding to the partial pressure of oxygen actually observed.     

Alkaloids of far-eastern species ofThalictrum. IV

Summary The alkaloid composition of four far-eastern species ofThalictrum — Th. amurense, Th. contortum, Th. filamentosum, andTh. minus — have been studied, for the first time in the case of the first three species.Th. amurense contains -allocryptopine and thalictrisine, andTh. contortum contains -allocryptopine. Glaucine and thalicsimidine have been found inTh. filamentosum, and argemonine has been isolated fromTh. minus for the first time.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Pacific Ocean Institute of Bioorganic Chemistry, Far-Eastern Scientific Center of the Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 788–791, November–December, 1976.     

Synthesis, Crystal Structure Determination, and Physicochemical Study of the Nickel(II) Complex of 4-(Pyridyl-2)-1,2,4-triazole

A new trinuclear nickel(II) complex with 4-(pyridyl-2)-1,2,4-triazole (pytrz), [Ni₃(pytrz)₆(H₂O)₆](NO₃)₆, has been synthesized, and its crystal structure has been determined. The compound was studied by X-ray phase analysis (XRPA), magnetochemical measurements, and electronic and IR spectroscopy.