The Claisen-Schmidt reaction with heterocyclic analogs of o-hydroxyacetphenone

Claisen-Schmidt condensation of 4-hydroxy-3-acetyl-6-methylpyrid-2-one, and its N-methyl and N-phenyl derivatives with aromatic aldehydes is investigated, and it is shown that the products of this reaction are 3-cinnamoyl and not 6-styryl derivatives.     

Kerr constants and conformations of certain arylmethylsulfones

Conclusions The conformations of the arylmethylsulfones in solution are such that the plane of the aromatic ring is shielded by one of the SO bonds.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2693–2696, December, 1976.The authors would like to thank G. Ya. Cheryukanova for aid in this work.     

Investigations in the field of depsipeptides Communication 44. Mass spectrometric study of cyclodidepsipeptides-2,5-diketomorpholines

Conclusions The fragmentation of cyclodidepsipeptides during electron impact was investigated. The nature of the hydroxy and amino acid residues contained in the 2,5-diketomorpholines can be established on the basis of the mass spectra.For the preceding Communication, see [1].Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 1539–1543, September, 1966.     

Mass-spectrometer investigation of 3, 6-dialkyl-2, 5-diketopiperazines

Analysis of mass-spectra of various 2, 5-diketopiperazines gives the basic fragmentation rules for their molecular ions, and the effects of nature and positions of substituents on the process.Mass-spectrometry Laboratory of the Institute of the Chemistry of Natural Compounds.Antibiotics Chemistry Laboratory of the Institute of the Chemistry of Natural Compounds.     

Steric structure of phosphorus-contaiming heterocycles

Conclusions The steric structure of 3-halo-1-thia-3-phosphethanes with a tetracoordinated phosphorus atom was investigated by the methods of dipole moments and Kerr constants, enlisting data on quantum chemical calculations of the energies of the conformations.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2240–2244, October, 1973.The authors would like to thank I. M. Shermergorn for providing the samples for the investigations.     

Cotton-mouton constants and spatial structure of pyridiniumethane derivatives and their analogs in aqueous media

A conformational analysis has been performed on 1,2-dipyridiniumethane and 1,2-diisoquinoliniumethane, using data on the Cotton-Mouton effect in water and in methanol. It has been shown that, in comparison with the 1,2-dibenzyl derivatives, in aqueous media, an abnormally high excess of the gauche conformer over the trans conformer is observed, an effect that is attributed to the formation of hydrate bridges.Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2766–2771, December, 1991.     

Kerr constants and dipole moments of aminobenzoic acids in dioxane

Aminobenzoic acids in dioxane have been investigated by dipole moment and Kerr effect methods.m-Aminobenzoic acid exists in a solution mainly (60 %) in thesyn-form. Inp-aminobenzoic acid, conjugation flattens the pyramidal configuration of the nitrogen atom, which is even more flattened ino-aminobenzoic acid owing to an intramolecular hydrogen bond.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 859–861, May, 1994.