Synthesis and asymmetric oxidation of thioglycosides derived from neomenthanethiol and α-d-galactose

6-Deoxy-6-[(1S,2S,5R)-2-isopropyl-5-methylcyclohexylsulfanyl]-1,2:3,4-di-O-isopropylidene-α-d-galactopyranose was synthesized in 94% yield from 1,2 : 3,4-di-O-isopropylidene-α-d-galactopyranose and neomenthanethiol, and its oxidation gave the corresponding diastereoisomeric sulfoxides in up to 84% yield and de values of up to 52%. The isopropylidene protective groups were removed from the sulfide and sulfoxides by treatment with trifluoroacetic acid in chloroform.     

Synthesis and oxidation of thioglicosides underlain by neomenthanethiol,D-glucose,and D-fructose

Synthesis of sulfides proceeding from neomenthanethiol, 1,2-O-isopropylidene-α-D-glucofuranose and 2,3:4,5-di-O-isopropylidene-β-D-fructopyranose was performed to get 65 and 54% yield respectively. Oxidation of the sulfides afforded diastereomeric sulfoxides in the yields from 40 to 53%, and diastereomeric excess (de) up to 36%. After removing the isopropylidene protection from 1-deoxy-1-[(1S,2S,5R)-2-isopropyl-5-methylcyclohexylsulfanyl]-2,3:4,5-di-O-isopropylidene-β-D-fructopyranose a water-soluble sulfide was obtained.     

Structural Inhomogeneity in Electrolyte Solutions: The Calcium Perchlorate–Water System

A new approach has been proposed to study the structure of aqueous electrolyte solutions. NIR, Raman and attenuated total reflectance, Fourier transform infra-red (ATR FTIR) spectra have been measured for aqueous calcium perchlorate solutions in the 0.22–4.3 mol·L^?1 (0.22–7.46 mol·kg^?1) concentration range at 25 °C. By the methods of principal component analysis (PCA) and multivariate curve resolution—alternating least squares (MCR-ALS) the number, spectra and concentration profiles have been determined for spectroscopically distinguishable forms of water and ClO ₄ ^? ion in solutions. The results have been analyzed using a phenomenological model, establishing thereby: concentration ranges for structural rearrangements of the solution, the nature of structural microirregularities and different states of the ClO ₄ ^? ion in the areas of domination of the natural water structure, and of cybotactic groups of calcium perchlorate hexa and tetra hydrates.     

Cross sections of the interactions of He nuclei with protons

⁴He-p collisions at two values of⁴He momenta 8.6 GeV/c and 13.6 GeV/c as well as the³He-p collisions at 13.5 GeV/c have been studies using the one-meter JINR hydrogen bubble chamber. Total, elastic, topological and reaction cross sections have been measured. The cross sections have been determined on a sample of minimum biased events.     

Decomposition of cyclic and linear N-acetyl-N-trimethylsilyl-amidophosphites

Conclusions N-Acetyl-N-trimethylsilylamidophosphites when heated undergo decomposition to give the corresponding silyl phosphites, which decomposition is facilitated by adding electron-acceptor substituents to the phosphorus atom.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 672–675, March, 1977.     

Synthesis of Chiral 3,4-Dihydropyrimidin-2(1H)-one Derivatives and Their Stereoselective Chlorination with Chlorine Dioxide

Russian Journal of Organic Chemistry - Optically active derivatives of 3,4-dihydropyrimidin-2(1H)-one have been synthesized on the basis of myrtenal and methyl...     

Rearrangement of the Binuclear K4Mo2Cl8 Cluster Structure in the Process of Its Oxidation in HCl Solution

Russian Journal of General Chemistry - Batch-type spectroscopic and continuous potentiometric titration of K4Mo2Cl8 with potassium dichromate in 1 M hydrochloric acid was carried out. Intermediate...     

Proton-proton and deuteron-deuteron correlations in interactions of relativistic helium nuclei with protons

The reactions⁴Hep pp+X,³Hep pp+X and⁴Hep ddp have been investigated and the correlation function has been measured for protons and deuterons with small relative momenta. Strong positive correlation has been observed for protons related mainly to the final state interactions in¹S₀ state. The root mean square radius of the proton source calculated from the correlation function has been found to be equal to (1.7±0.3) fm and (2.1±0.3) fm for⁴He and³He respectively. It agrees with the known radii of these nuclei.We would like to thank Dr R. Lednicky for discussion, helpful suggestions and for making available the computer program that calculates the theoreticalpp correlation function. The authors also thank Dr D.H. Boal for providing the results of the two-deuteron correlation function calculations.     

The deuteron D-state probability

A method of direct determination of the deuteron D-state probability from the experiment, based on the d ↑ p → ppn reaction analyzis is suggested. Using the known results on the vector analyzing power in elastic NN-scattering, the values of the overall nucleon polarization and the deuteron vector polarization have been obtained. The probability of the deuteron D-state is estimated to be w _D = 0.078 ± 0.046.