Ring-chain tautomerism of substituted hydrazones

The reaction of thiiranes with hydrozones leads primarily to 2-mercaptoalkylhydrazones that are capable of undergoing reversible isomerization to the corresponding perhydro-1,3,4-thiadiazines or (in the case of unsubstituted aldohydrazones) to 3-aminothiazolidines. The reaction mixtures, which contain products of side and secondary reactions, were analyzed by Chromatographic mass spectrometry. It is shown that the principal products of mercaptoethylation and mercaptopropylation of acetone hydrazone exists in the form of tautomeric mixtures of chain and ring forms and that the introduction of a methyl substituent in the 6 position of the ring leads to a shift of the equilibrium to favor the perhydro-1,3,4-thiadiazine.See [1] for our preliminary communication; see [2] for communication 12.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1637–1647, December, 1979.Original article submitted June 27, 1979.     

Enthalpy of mixing in the propylene oxide–dimethylformamide and propylene oxide–ethylene glycol systems

Heat of mixing of propylene oxide with N,N-dimethylformamide and ethylene glycol has been determined by means of microcalorimetry. Theoretically suggested choice of the aprotic solvent as a selective separating agent for the propylene oxide–methanol binary mixture has been experimentally justified.     

Synthesis of substituted 2,5-diazabicyclo[2.2.1]heptanes

A new method is proposed for the synthesis of substitituted 2,5-diazabicyclo[2.2.1]heptanes from 1-(tert-butoxycarbonyl)-4-tosyloxy-2-(tosyloxymethyl)pyrrolidine.¹H NMR spectroscopy indicated multiple conformations of 2-(tert-butoxycarbonyl)-2,5-diazabicyclo[2.2.1]heptanes in solution.St. Petersburg State University, 198904 St. Petersburg, Russia. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 501–503, April, 2000.     

Azabrendanes. I. Synthesis,structure and spectral parameters of N-(arylsulfonyl)-exo-2-hydroxy-4-azatricyclo[4.2.1.03,7]nonanes

A number of N-(arylsulfonyl)bicyclo[2.2.1]hept-2-enendo-5-methylamines have been synthesized from bicyclo[2.2.1]hept-2-en-endo-5-carbonitrile via reduction of the latter by lithium aluminum hydride and subsequent reactions of the resulting amine with arylsufonyl chlorides. The structures and stereochemical homogeneity of the products have been supported by the analysis of ¹H NMR spectra and by COSY-experiments. The reactions of the sulfonamides with peroxyphthalic acid are accompanied by intramolecular cyclizations and are completed by the formation of N-(arylsulfonyl)-exo-2-hydroxy-4-azatricyclo[4.2.1.0^3,7]nonanes. The structures of the substituted azabrendanes have been confirmed by spectral methods. The molecular structure of N-(p-methoxy-carbonylaminophenylsulfonyl)-exo-2-hydroxy-4-azatricyclo-[4.2.1.0^3,7]nonane 8j has been determined by X-ray diffraction analysis. © 1997 John Wiley & Sons, Inc.     

Deuteron and triton production with high energy sulphur and lead beams

Proton and deuteron production has been observed in S+S and S+Pb collisions at 200 AGeV and in Pb+Pb reactions at 158 AGeV at the CERN SPS accelerator. For Pb+Pb triton production was also measured. The p and d spectra as well as the p and t spectra were observed in similar rapidity ranges and over similar ranges of transverse momenta per nucleon, making it possible to interpret the cross sections of the composite particles in terms of coalescence mechanisms. Volumes of homogeneity were extracted and compared to pion-pair HBT interferometry results. Special attention is given to the dependence on transverse mass, centrality and rapidity. Received: 23 July 2001 / Revised version: 16 November 2001 / Published online: 25 January 2002     

Synthesis of sultams by cycloalkylation of (alkoxycarbonylmethane)sulfonanilides

(Methoxycarbonylmethane)sulfonanilides are alkylated by α, ω-dihaloalkanes in K₂CO₃-DMF with the formation of sultams. A high sensitivity has been detected for the reaction rate on the electronic effect of substituents in the aromatic nucleus, although substituents in the ortho position do not obstruct the reaction and in the case of 2,6-disubstituted derivatives the reaction rate and sultam yield were maximal. Tertiary sulfonamides form derivatives of 1-sulfamoylcyclopropanecarboxylic acid under these conditions. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 605–617, April, 2008.     

Cyclocondensation of 3,3-diamino-1-phenylpropenone with pyridine and quinoline N-oxides containing an electrophilic group in position 3

The cyclocondensation of the N-oxide of the methyl ester of nicotinic acid with 3,3-diamino-1-phenylpropenone and the ethyl ester of 3,3-diaminoacrylic acid in the presence of benzenesulfonyl chloride gives the corresponding 2,7-naphthyridines. The cyclocondensation of 3,3-diamino-1-phenylpropene with the N-oxides of dimethyl 3,5-pyridinedicarboxylate and quinolines containing an electrophilic group at in position 3 yields products of the nucleophilic attack of the carbon nucleophilic site of the enediamine at the 2-pyridine ring position, while the amine group binds to the exocyclic electrophilic group. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 578–584, April, 2008.     

Chemoselective cyclocondensation of α-acylacetamidines with 2-methylsulfanyl-4,6-dichloropyrimidine-5-carbaldehyde

Cyclocondensation of α-acylacetamidine with 2-methylsulfanyl-4,6-dichloropyrimidine-5-carbaldehyde proceeds chemo- and regioselectively involving replacement by the α-carbon of the amidine of the chlorine in the aromatic ring and a reaction of the amino group with the formyl group.     

Rearrangement of O-vinyl-α-(amino-carbonyl)acetamidoximes to 2-aminopyrroles and 2-pyrrolinones

Rearrangement and cyclization of O-vinyl-α-(aminocarbonyl)acetamidoximes gives two isomeric 2-aminopyrroles and/or 2-pyrrolinones and this depends on the rearrangement route. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1328–1334, September, 2007.