13C NMR spectra of biologically active compounds. II. 11-Deoxy-16- and 17-aryloxyprostaglandins

The¹³C NMR spectra of the initial -aryloxy chains and the final 16-and 17-aryloxyprostaglandins of the 11-deoxy series have been investigated, and stereochemical assignments have been made for the diastereomeric pairs. A weakening of the diastereotopic effects in the spectra of the 15- and 16-methyl-substituted 16- and 17-phenoxypropstaglandins to 0.1 ppm has been shown.Institute of Chemistry, Bashkir Branch, Academy of Sciences of the USSR, Ufa. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 610–618, September–October, 1985.     

Synthesis and properties of diaminothiadiazoles

Refined synthetic procedure for preparation of 3,5-diamino-1,2,4-thiadiazole and 2,5-diamino-1,3,4-thiadiazole based on the reaction of dithiourea or amidinothiourea with hydrogen peroxide is developed. The optimal reagents ratio was found, and monitoring methods were developed. It resulted in the increase of the target product yield and in a shorter reaction time. On the basis of 2,5-diamino-1,3,4-thiadiazole the alkylsubstituted 1,3,4-diaminothiadiazolidines were synthesized. The compounds prepared were characterized by the elemental analysis data, the IR, ¹H NMR, and electronic spectra, and also by mass spectrometry.     

Structural analogs of tetrapyrrole macrocycles and their biological properties

The review summarizes data on the synthesis and properties of analogs of ABBB-and ABAB-type tetrapyrrole macrocycles and their metal complexes. The structural features of these compounds are discussed. Data on aromaticity and biological properties are considered. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 663–679, April, 2007.     

Reinforced track membranes in methods for estimating the quality of natural and drinking water

Reinforced track membranes are used for the first time to study element distribution between particles of various sizes and other water components. The properties of the reinforced track membranes are considered. Factors affecting the quality of water in the Volga River in the region of the water intake of the city of Dubna in the Moscow region and potable water in various districts of the city in are characterized by the fractional composition of macro- and microcomponent.     

Reaction of sodium N-benzylideneglycinate with dialkyl chlorophosphites in the presence of water

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Metastable Austenite Steel Structure After Thermomechanical Processing in Different Modes

Russian Physics Journal - The paper studies the transformation-induced plasticity of steel chromium-nickel-molybdenum structure depending on the reduction ratio during warm rolling. Optical and...     

Diode laser spectroscopy using two modes of an InAsSb/InAsSbP laser near 3.6 μm

A new type of multimode semiconductor laser, based on InAsSb/InAsSbP heterostructures, is described. This continuous laser working in a broad range of temperatures (30–100 K) was tested using a closed-cycle He-cryostat and its quality was demonstrated using the laser spectroscopy of gases absorbing in the 2800 cm^-1 region. Two different laser modes were used to increase the spectral range. The spectral characteristics and tunability of the laser were explored as a function of heat-sink temperature and drive current with the aim of developing its use for high–resolution spectroscopy. The laser has potential applications in the field of chemistry, atmospheric research and the study of the kinetics of reactive species. Received: 18 October 1999 / Revised version: 10 May 2000 / Published online: 16 August 2000     

Synthesis of <Emphasis Type="Italic">N</Emphasis>-alkylthiadiazole-containing macroheterocyclic compounds of ABBB type

New substituted unsymmetrical macroheterocyclic compounds with a fragment of 1,3,4-thiadiazoline were obtained by condensation of 5-amino-2-imino-3-pentyl-1,3,4-thiadiazoline or 5-amino-3-dodecyl-2-imino-1,3,4-thiadiazoline with 1,1-dimethoxy-3-iminoisoindoline in methanol. The compounds obtained were characterized by the IR, electron and 1H NMR spectroscopy, mass spectrometry, and elemental analysis.     

Periodic microwave absorption in superconducting whiskers

The microwave absorption and structural studies of BiSrCaCuO (2212) whiskers have been performed. The low-angle boundaries in the (a, b) and (a, c) planes have been observed. The periodic microwave absorption signal indicated the flux quantization in a system of weak links and superconducting loops formed on the boundaries. Regular character of this signal suggests possible applications in SQUID magnetometry. Lower Josephson critical fieldH _clJ=1.6 Oe and the critical temperatureT _c=89 K have been determined. The Josephson penetration depth was estimated from the Ginzgurg-Landau, and Clem models.     

Synthesis and properties of mixed-substituted nickel triazolephthalocyaninates

Homo- and mixed-substituted nickel triazolephthalocyaninates were synthesized by the reactions of nickel complexes of substituted 3,5-bis(3-iminoisoindolin-1-ylideneamino)-1,2,4-triazoles with 4-phenoxyphthalonitrile and 4-phenylthiophthalonitrile. The structures of these compounds were established by UV-Vis and IR spectroscopy, mass spectrometry, and elemental analysis, and their physicochemical properties were studied.