Vibrational spectra and conformations of 2- and 3-methylbicyclo[4.4.0]decanes

The conformations and heats of formation of all trans(T)- and cis(C)-2- and 3-methyl-substituted T- and Cbicyclo[4.4.0]decanes (BD) were calculated by the MM2 method of molecular mechanics. It was shown that the conformationally mobile T-2-Me-CBD and T-3-Me-CBD can exist in normal conditions as an inseparable mixture of conformers with a different equatorial or axial orientation of the Me groups. The Raman scattering (RS) spectra of TBD and CBD were investigated. RS bands whose frequencies were sensitive to the type of ring linkage and orientation (but not the position) of the Me substituents were detected in the 700–300 cm^–1 region.A. V. Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, 117912 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 9, pp. 2089–2097, September, 1992.     

Spectroscopic and quantum chemical investigation of enol-enol tautomerism of 2-acetyltetronic acid

Vibratonal spectra of 2-acetyltetronic acid (ATA) (3-acetyloxolane-2,4-dione) were investigated in different aggregate states.Ab initio quantum chemical calculations (3-21G basis set) of 2-formyltetronic acid as analogue of ATA and semi empirical calculation of ATA were carried out. The tautomeric forms of ATA can be arranged in the following series with respect to thermodynamic stability (in decresing order):1a,1b,2a,2b.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1043–1048, June, 1995.     

Synthesis of cyclic polysulfides by the reaction of trimethylvinylsilane with S8 in the presence of Fe3(CO)12

Reaction of trimethylvinylsilane with S₈ in the presence of Fe₃(CO)₁₂ yielded the following compounds: S₂Fe₂(CO)₆, S₂Fe₃(CO)₉, 1-trimethylsilyl-2,3,4,5,6-pentathiacycloheptane, 1,4-di(trimethylsilyl)-2,3,6-trithiacycloheptane, 1,4-di(trimethylsilyl)-2,3,6,7-tetrathiacyclooctane. An X-ray analysis was performed for the two latter polysulfides.     

New design of cationic alkyl glycoglycerolipids toxic to tumor cells

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Synthesis of new carbohydrate-containing cationic alkyl glycerolipids with antitumor activity

Russian Chemical Bulletin - New non-phosphorous carbohydrate-containing cationic alkyl glycerolipids bearing a ter- minal glycosyl moiety were synthesized. An approach used for the preparation of...     

Synthesis of trimethylsilyl-μ-S,S′-ethylenedithiolatohexacarbonyldiiron and 1-methyl-3-trimethylsilyl-2,5-dithiacyclopentane by reaction of trimethylvinylsilane with S8 in the presence of Fe3(CO)12

Reaction of trimethylvinylsilane with S₈ in the presence of Fe₃(CO)₁₂ led to 1-trimethylsilyl-μ-S,S′-ethylenedithiolatohexacarbonyldiiron and 1-methyl-3-trimethylsilyl-2,5-dithiacyclopentane. An X-ray study was carried out on compound VI.