Russian Chemical Bulletin最新文献

A facile synthetic approach is reported toward ligands based on 2-(2-pyridyl)quinazoline, which are suitable for the preparation of both water-soluble and liposoluble chelate complexes with lanthanide(iii) cations. The ligands contain an additional rigid chelating moiety, such as the carboxyl group or the diethylenetriaminetetraacetic acid residue. The luminescence properties of the new cationic Eu^III and Tb^III complexes were studied.

A new representative of 1,2-diphosphaferrocenes containing p-fluorophenyl substituents on the 1,2-diphosphacyclopentadienyl ring was synthesized. Its structure was confirmed by multinuclear NMR, IR, and Mössbauer spectroscopy, and its electrochemical properties were studied.

Fused 2-amino-3-cyano-4H-pyrans were synthesized by the tandem Knoevenagel—Michael reaction. A previously unknown version of the ring opening of 2-amino-3-cyano-4H-pyrans giving substituted 2,6-dicyanoaniline was discovered. The structure of the latter compound was established by X-ray diffraction.

Reactions of 12H-quinoxaline[2,3-b]phenoxazine (QOPO) derivatives with the Co^II and Zn^II hexafluoroacetylacetonates accompanied by protonation of the starting bases result in stable complexes [QOPOH]⁺[M(hfac)₃]⁻ whose structure was determined by X-ray diffraction and by ¹H and ¹⁵N NMR spectroscopy. The complexes are characterized by long-wavelength absorption (560–664 nm) and fluorescence in the red region (λ_fl = 674–805 nm). The relative energies of the protonated tautomers N(14)—H and N(7)—H were determined using the results of B3LYP–D3BJ/6-311G++(d,p) density functional calculations with inclusion of D3BJ dispersion correction. A SQUID magnetometry study of the static and dynamic magnetic properties of the Co^II complex revealed that it behaves as a field-induced single-ion magnet.

A new synthetic approach to 2,2′:6′,2″-terpyridines bearing the CF₃ and HCF₂ substituents at the C(4′) atoms that involved the reaction of lithium 3-polyfluoroalkyl-1,3-ketoenolates with ammonium acetate in glacial AcOH was developed.

Catalyst-free addition of diphenylphosphine oxide to 1,4-diorganyl-4-(organylamino)-alk-2-yn-1-ones proceeded chemo-, regio-, and stereoselectively to afford new Z-3-diphenylphosphoryl-1,4-diorganyl-4-(organylamino)alk-2-en-1-ones in up to 75% yield. The synthesized compounds are promising candidates for organic synthesis and pharmaceutical research.

New homodimers of 1,2,3-triazolyl nucleoside analogs based on 6-methyluracil, which are linked by the polymethylene linker at the N(1) or N(3) atoms, were synthesized. Screening of in vitro antiviral activity against influenza A virus (H1N1) and Coxsackievirus B3 revealed the lead compound that in vitro inhibited the replication of Coxsackievirus B3 with a half-maximal inhibitory concentration (IC₅₀) and a half-maximal cytotoxic concentration (CC₅₀) of 30.1 and >374 µmol L⁻¹, respectively. A dependence of the antiviral activity on the length of the polymethylene linker connecting the 6-methyluracil and 1,2,3-triazolyl-β-d-ribofuranosyl fragments was found.

A number of new conjugates of dehydroabiethylamine and adamantane was obtained using a three-step synthetic scheme in order to study the effect of linker type and length on biological activity. The inhibitory activity of the synthesized compounds toward the DNA repair enzyme Tyrosyl-DNA phosphodiesterase 1 was studied. The compounds are potent inhibitors, exhibiting activity in micromolar concentrations.

A simple synthetic route to poorly available polycyclic systems with a [1,2,5]oxadiazolo-[3,4-b]quinoxaline backbone has been developed, which is based on the sequence of nucleophilic aromatic substitution of hydrogen and the Scholl cross-coupling. According to the data from electrochemical and photophysical measurements, the synthesized compounds can be potentially considered as the narrow-gap (from 1.97 to 2.34 eV) n-type organic semiconductors, the energy levels of which are comparable to those of top commercially available electronic semiconductors.

A method comprising the use of a fluorinating agent, the Ishikawa’s reagent, at one of its steps was developed for the synthesis of 1,3,5-trifluoroadamantane-7-isocyanate from 3,5,7-trifluoroadamantane-1-carboxylic acid and diphenylphosphoryl azide. The reaction of 1,3,5-trifluoroadamantane-7-isocyanate with fluoroanilines gave 1,3-disubstituted ureas in the yields of 58–73%. The influence of number of the fluorine atoms in the adamantyl moiety on the melting point, lipophilicity, and water solubility of ureas was estimated, which allows one to intentionally tune these important properties of ureas as promising enzyme inhibitors. The molecular docking revealed the effectiveness of 4-({4-[3-(3,5,7-trifluoroadamantan-1-yl)ureido]cyclohexyl}oxy)benzoic acid in the inhibition of p38 MAPK, c-Raf and hsEH.