Synthesis of a disaccharide of phenolic glycolipid from Mycobacterium leprae (PGL-I) and its conjugates with bovine serum albumin

Russian Chemical Bulletin - Terminal disaccharide fragment of phenolic glycolipid from Mycobacterium leprae (PGL-I) was synthesized as a glycoside with 4-(2-aminoethoxy)phenyl aglycon. The obtained...     

On the factors governing the minimum size of light beams during self-focusing

The final stage of self-focusing of 500-ps pulses of a neodymium laser in silicate and phosphate glasses and in the nonlinear liquids perfluorooctane, benzene, and toluene is studied theoretically and experimentally. The formation of spatial solitons, which are stable due to the nonlinearity saturation, is demonstrated. It is found that the intensity of the nonlinearity saturation is close to that of the threshold breakdown for glasses and the role of stimulated Raman scattering is significant for liquids.     

Electron-impact mass spectra of nitromethylpyridines

Conclusions Under conditions of electron-impact mass spectrometry, nitromethylpyridines form molecular ions whose stability depends on the position of the substituent. The nature of the fragmentation of the molecular ions permits us to distinguish trinitromethyl from dinitromethyl substituents.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2785–2787, December, 1985.     

Quantum chemical calculation of gas-phase borenium ions

Conclusions A CNDO/2 calculation of C₃H₇NB⁺ borenium ions predicts the greater thermodynamic stability of cyclic structures in comparison with the corresponding acyclic structures.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2619–2620, November, 1987.     

Synthesis and some properties of gem-dichlorocyclopropane carboxaldehyde acetals and cyclopropane carboxaldehyde acetals

α,β-Unsaturated aldehyde acetals add :CCl₂ (obtained in accordance with Makosza procedure) to form gem-dichlorocyclopropanecarboxaldehyde acetals (1) in high yields when the ratio of reactants is no less than 1:4. The addition of :CCl₂ to polyunsaturated aldehyde acetals in the above conditions proceeds regioselectively at double bonds enriched by electrons. Compounds 1 are reduced by sodium in liquid ammonia to give cyclopropanecarboxaldehyde acetals (2). Both 1 and 2 are hydrolized by dilute H₃P0₄ to the corresponding aldehydes and are added to vinyl ethers in the presence of BF₃·Et₂O to produce only 1:1 adducts which are hydrolyzed by a mixture of AcOH-AcONa-H₂O to give β-formylcyclopropanes which were previously unknown.