The first example of direct heterylation of calixpyrrole

1,2,4-Triazine derivatives react with calixpyrrole to give stable nucleophilic addition products.     

New 5-arylamino-4-(5-nitrofuran-2-yl)pyrimidines as promising antibacterial agents

A facile synthetic approach to 5-arylamino-4-(5-nitrofuran- 2-yl)pyrimidines by the Buchwald–Hartwig cross-coupling with various anilines has been developed. All synthesized compounds demonstrated a significant level of in vitro antibacterial activity against Neisseria gonorrhoeae, Streptococcus pyogene and Staphylococcus aureus, including their drug-resistant strains, which is much higher than that of the commercial drug Spectinomycin.     

Hydrolytic conversions of 2, 4-diazido-6-alkoxy-s-triazines

Translated from Khimiya Geterotsilicheskikh Soedinenii. No. 1, pp. 135–136, January, 1990.     

Bis(acetylaryl) podands in the synthesis of fluorine-containing bis(β-diketones) joined by a polyether spacer

O-Alkylation of 2-acetylphenols with α,ω-dichloro derivatives of oligoethylene glycols in the presence of KOH and Al₂O₃ in DMF gave the corresponding podands. Their condensation with ethyl trifluoroacetate afforded fluorine-containing bis(β-diketones) with the aryl fragments linked by conformationally flexible polyether spacers.     

Synthesis,structures, and magnetic properties of crystals of dinuclear copper(II) and cobalt(II) complexes with 3-(3,5-dimethylpyrazol-1-yl)-6-R-1,2,4,5-tetrazines

Dinuclear complexes of Cu^II with 3-(3,5-dimethylpyrazol-1-yl)-6-(2-hydroxyethylami-no)-1,2,4,5-tetrazine (1) and CoII with 3-(3,5-dimethylpyrazol-1-yl)-6-(piperidin-1-yl)-1,2,4,5- tetrazine (2) were synthesized and structurally characterized, and the magnetic (SQUID) and resonance (EPR) properties of van der Waals crystals based on these complexes were studied. Unusual behavior of the effective magnetic moment μ_eff(T) is observed at T < 60 K. A nonmonotonic increase in μeff(?) for 1 (s~6 %) and a 20% reduction of μeff(?) for 2 have a common origin and are due to the influence of spin-orbital coupling on the character of the splitting between the t2g and eg levels of the central ion. Distortions of the coordination site “switch on” a positive (1) or negative (2) contribution of the orbital magnetic moment near 6 K. Irreversible temperature behavior of μeff(T) in the heating and cooling regimes in the vicinity of 60 K suggests that the character of structural distortions and the magnetic properties are related to ligand geometry. This factor plays a significant role in crystal engineering of magnetoactive structures with polynitrogen ligands.     

Synthesis and Crystal Structure of (<Emphasis Type="Italic">S</Emphasis>)-2-((<Emphasis Type="Italic">S</Emphasis>)-2-(<Emphasis Type="Italic">N</Emphasis>-Ts-Amino)-3-methylbutanoyl)-3-(1H-indol-3-yl)-6-phenyl-3,4-dihydro-1,2,4-triazin-5(2H)-one

Abstract  

The diastereoselective synthesis, NMR and X-ray structure of (S)-2-((S)-2-(N-Ts-amino)-3-methylbutanoyl)-3-(1H-indol-3-yl)-6-phenyl-3,4-dihydro-1,2,4-triazin-5(2H)-one—a potential antivirus agent are reported. The compound crystallizes in the triclinic space group P1 with unit cell parameters: a = 5.9259(6) ?, b = 9.6370(12) ?, c = 12.9541(9) ?, α = 109.210(9)°, β = 90.804(7)°, γ = 105.074(10)° and Z = 1.     

σ<Superscript>H</Superscript>-Adducts of <Emphasis Type="Italic">N</Emphasis>-alkylpyrazinium and quinoxalinium salts with nucleophiles. The <Superscript>1</Superscript>H and <Superscript>13</Superscript>C NMR spectra and the crystal structures of P-adducts

The previously unknown addition products of P-nucleophiles to 5-aryl- and 5-hetaryl- 2,3-dicyano-1-ethylpyrazinium salts and to 5-aryl- and 5-hetaryl-14nethylquinoxalinium salts were synthesized. The three-dimensional structures of the P- σ^H-adducts of the 1,4-diazine series were established by X-ray diffraction.     

Mass spectrometry of nitrogen heterocycles. 3. Thermal intramolecular cyclization of 2-azolylaminopyridines

Mass spectrometric fragmentation or decay of 2-azolylaminopyridines containing a carbonyl group in the ortho-position results in elimination of a neutral molecule (ammonia, ethanol, hydrogen sulfide). This decay process is accompanied by intramolecular cyclization to form an ion with a triazolo[1,5-a]pyrido[2,3-d]pyrimidine structure.For Communication 2, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 101–104, January, 1991.     

Zwitter-ionic c-σ-adducts based on 4,6-dinitrotetrazolo[1,5-a]pyridine

Translated from Khimiya Geterotsiklieheskikh Soedinenii, No. 8, pp. 1146–1147, August, 1992.     

Theoretical studies of the electronic and structural features of the fragments of dihydropholate reductase inhibitors

The effects of the structural characteristics of dihydrofolate reductase (DHFR) inhibitors on their tuberculostatic activity have been analyzed. It was shown that an increase in the electron density on bonds and atoms in the ring led to an increase in the biological activity of the compounds. A correlation was found between the biological activity and the characteristics of the critical points of electron density of bonds. The 3D- and 4D-QSAR studies with the CiS algorithm revealed the pharmacophore and antipharmacophore fragments of DHFR inhibitors, and regions of the receptor that are responsible for the biological action of dihydropyrimidines were found. Receptor ligand complexes were modeled. For a series of drugs containing a podand chain, it was found that the chain performed only the transport membranotropic function because the increase in the size of molecules due to the podand chain gives rise to steric hindrances when the chain is built in the receptor cavity.