Synthesis of <Emphasis Type="Italic">N</Emphasis>-[4-hydroxy(alkoxy,acyloxy)-3-alkoxy-benzylidene]-1-(1-adamantyl)ethanamines from 1-(1-adamantyl)ethanamine hydrochloride (Rimantadine)

Reactions of 1-(1-adamantyl)ethanamine with vanillin, vanillal, veratraldehyde, 3-ethoxy-4-methoxybenzaldehyde, and 4-formyl-2-methoxy(ethoxy)phenyl esters gave previously unknown Schiff bases containing an adamantane fragment.     

Mechanisms of Reactions of H2O and NH3 Molecules with (≡Si–O)3Si⋅and (≡ Si–O)3Si–⋅ Radicals on the Silica Surface

Spin traps, which are diamagnetic centers (SiO)₂Si, are used to register low-molecular radicals OH, NH₂, and H formed by the reactions of H₂O and NH₃ molecules with the radicals (Si–O)₃Si and (Si–O)₃Si–O stabilized on the silica surface. The experimental data and the results of quantum-chemical calculations for model systems are used to determine the mechanism and thermochemical characteristics of these reactions. A new paramagnetic center (Si–O)₂SiNH₂ was identified on the silica surface, and its radiospectroscopic characteristics are determined.     

Spectral luminescence properties of 1- and 2-alkyl(cycloalkyl) derivatives of benzo[f]quinoline

The absorption and fluorescence spectra of alcohol solutions of 3-aryl-substituted benzo[f]-quinolines were investigated, and the fluorescence quantum yields were measured. It was established that the indicated compounds have intense absorption in the UV region and fluorescence at 350–450 nm. The fluorescence quantum yields range from 5 to 70%, depending on the substituents. The introduction of aromatic substituents in the 1 and 3 positions of benzo-[f]quinoline ring raises the fluorescence quantum yields. A methyl group in the 2 position of the molecule leads to a decrease in the fluorescence quantum yield. Benzo[f]quinoline derivatives that contain a cyclopentene ring in the 1 and 2 positions fluoresce intensely (=40–60%), while cyclohexene and cycloheptene condensed in the same positions cause a decrease in the fluorescence yield to 7–13%; this is associated with the three-dimensional structure of these molecules.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1237–1240, September, 1977.     

Synthesis of spirocyclic benzo[f]quinoline derivatives by cascade heterocyclization of dimedone, 2-naphthylamine, and formaldehyde

The three-component condensation of dimedone, 2-naphthylamine, and formaldehyde in aliphatic alcohols under mild conditions gives in high yields the corresponding N-alkoxymethyl benzo[f]quinoline derivatives having a substituted 2-azaspiro[5.5]undecane fragment. The reaction involves formation of three new carbon-carbon bonds, two carbon-nitrogen bonds, and one carbon-oxygen bond, and the initial β-dicarbonyl system is conserved.     

Synthesis of 2,4-substituted 5,6-benzoquinolines

By the catalytic condensation of azomethines with aliphatic-aromatic and heterocyclic ketones, derivatives of 5,6-benzoquinoline containing thiophene or pyridine rings as substituents have been synthesized.     

Synthesis and Properties of Copper,Mercury, and Silver (2-Naphthyl)acetylenides

(Z)-2-Naphthylacetylene was synthesized by the reaction of (Z)-3-(2-naphthyl)-3-chloropropenal (prepared from 2-acetylnaphthalene) with aqueous NaOH in dioxane. The reactions of 2-naphthylacetylene with CuCl, [Ag(NH₃)₂]NO₃, and K₂[HgI₄] gave copper, silver, and mercury 2-naphthylacetylenides, respectively. Silver naphthylacetylenide reacts with iodine to give the iodoethynyl derivative, which readily takes up bromine across the triple bond.     

“Superslow” processes in the Ge-GeO2 system

A study was made of the charged state on a natural or an oxidized germanium surface during heat-and-field treatment. This study dealt with the kinetics of charging and discharging of superslow surface states. The thermal activation energy of these charging and discharging processes has also been evaluated. Conclusions are drawn about the possible nature of superslow traps in the Ge-GeO₂ system.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No.2, pp.79–86, February, 1976.In conclusion, the authors thank V. F. Kiselev for the useful discussion of this report and his valuable comments.     

Synthesis of Bifunctional Silica Container Particles on Antiseptic Micelles with Solubilized Curcumin and Assessment of Their Biological Activity

Colloid Journal - The features of the synthesis of SiO2 mesoporous container particles (MCPs) using a hybrid template represented by miramistin micelles with curcumin solubilized in them have been...     

Luminescence of Hybrid Nanostructures of InP@ZnS Colloidal Quantum Dots and <Emphasis Type="Italic">meso</Emphasis>-Tetra(3-pyridyl)porphyrin Molecules

The formation of hybrid nanostructures consisting of InP@ZnS colloidal quantum dots and mesotetra(3-pyridyl)porphyrin molecules adsorbed on the quantum dots has been studied. In such nanostructures, strong quenching of quantum dot luminescence and an increase in the emission intensity of porphyrin are observed due to nonradiative resonance energy transfer from colloidal quantum dots to porphyrin.     

Nature of radiation resistance of LFS oxyorthosilicate crystals doped with Ce,Sc, Ca,and Y ions

Optical and luminescence characteristics of Lu_2+2ySi_1-yO_5+y (LFS) scintillation crystals are studied before and after irradiation with doses to 45 Mrad from a ⁶⁰Co source. LFS crystals were doped with Ce³⁺, Sc³⁺, Ca²⁺, and Y³⁺ ions with various concentrations. The dependence of the radiation resistance of LFS crystals on Ce ion concentration is detected. For the crystal of composition Ce:Sc:Ca:Y:LFS, it was found that its optical transmission (OT) and pulsed cathodoluminescence (PCL) spectra before irradiation do not differ from the spectra measured after irradiation with a dose of 45 Mrad within experimental error. The nature of the radiation resistance of rare-earth lutetium oxyorthosilicates (LFS) is discussed.