Electronic Structure of Immunoactive Molecules of 8–Azagona–12,17–Dione

Using the semiempirical method of partial neglect of differential overlap (PNDO), we have calculated the wave functions, energies, orbital configurations of electronic states, oscillator strengths of transitions, electronic density distributions, and dipole moments for the molecule of biologically active 8–azagona–12,17–dione, containing a conformationally rigid –acyl––aminovinylcarbonyl fragment. It has been established that as to their orbital nature the excited lower and higher singlet electronic states of this molecule are of the n^*– and ^* type respectively. The results of the theoretical analysis are in good qualitative agreement with the spectral data on absorption and luminescence. The calculations of the intermolecular interaction of the compound under consideration with a medium show that the molecular systems under consideration can possess a dynamic multicenter structure.     

Ternary condensation of cyclic azomethines,aromatic aldehydes,and barbituric acid: A new approach to the synthesis of 8,15,17-triaza-d-homogonanes

New fused heterocyclic compounds of the 8,15,17-triaza-d-homogonane series have been obtained by ternary condensation of cyclic azomethines (1-methyl-3,4-dihydroisoquinolines) with aromatic aldehydes and barbituric acid in DMF.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2353–2355, September, 1996.     

IR Spectra and Structure of Immunoactive 8–Azasteroids in Model Compounds

The IR spectra of biologically active molecules of 8-azasteroids and model compounds in the region of C=O, C=C, C--N, and C--H vibrations (1800–1400 cm^–1) have been studied in detail. The structure of compounds containing isostructural and isoelectronic --acyl----aminovinylcarbonyl and --acyl----alkoxyvinylcarbonyl fragments have been analyzed. Interpretation of the structure of the IR spectra and of the specificity of the manifestation of the vibrational modes under consideration in the molecules of a particular class of 8-azasteroids is given. The electronic structure of the molecules under investigation complies with the model of mesomeric tautomerism of the aminovinyldicarbonyl fragment.