Metallation of N-vinylpyrroles and -indoles with Hg(OAc)2: N-vinyl vs. pyrrole nucleophilic sites

N-Vinylpyrroles and -indoles bearing electron-withdrawing substituents at the pyrrole ring are mercurated, with 1 equivalent of Hg(OAc)(2) in dry MeCN (20-80 °C), regioselectively at the vinyl group (yields are almost quantitative), while their congeners without electron-withdrawing functions are mercurated both at the N-vinyl group and the pyrrole ring.     

Arbuzov chemistry with chlorofullerene C(60)Cl(6): a powerful method for selective synthesis of highly functionalized [60]fullerene derivatives

We report Arbuzov-type reactions of chlorofullerene C(60)Cl(6) with trialkyl phosphites producing highly functionalized fullerene derivatives C(60)[P(O)(OR)(2)](5)H with high yields. The designed family of [60]fullerene phosphonic acids and their esters showed unusual properties which might find valuable material science applications.     

Magnetization-induced third-harmonic generation in nanostructures and thin films

This paper reports on the results of research into low-dimensional magnetic structures that have been intensively studied over previous decades due to the discovery of novel effects that are exhibited by these structures but not observed in bulk magnetic materials. A nonlinear optical analog of the magnetooptical Kerr effect is revealed in the optical third-harmonic generation in thin magnetic metallic films and nanogranular structures. It is shown that the magnetic nonlinear optical Kerr effect observed in the third harmonic exceeds the magnetooptical analog by more than one order of magnitude.     

Interrelation between optical and magneto-optical properties of MnSbBi(Pt,Co) films

Results of the study of optical and magneto-optical properties of MnSbBi(Pt, Co) films in a spectral region of 360–820 nm are reported. It is shown that the multilayer MnSbBi(Pt, Co) films obtained by magnetron sputtering possess considerable optical rotation in the geometry of the polar Kerr effect, which is as large as 0.5°–0.7° upon 5-h annealing of the films at 350°C. The spectral dependences measured for the magnitude of the polar Kerr effect showed that these films may be used for laser data recording in the short-wavelength spectral region, which substantially increases the recording density. Studies of the film structure by X-ray and electron diffraction analysis showed that the films have a polycrystalline structure, with granules 15–40 nm in size. Possible causes of a large magnitude of Kerr effect are analyzed.     

Neuronal store-operated calcium entry pathway as a novel therapeutic target for Huntington's disease treatment

Huntington's disease (HD) is a neurodegenerative disorder caused by a polyglutamine expansion within Huntingtin (Htt) protein. In the phenotypic screen we identified a class of quinazoline-derived compounds that delayed a progression of a motor phenotype in transgenic Drosophila HD flies. We found that the store-operated calcium (Ca(2+)) entry (SOC) pathway activity is enhanced in neuronal cells expressing mutant Htt and that the identified compounds inhibit SOC pathway in HD neurons. The same compounds exerted neuroprotective effects in glutamate-toxicity assays with YAC128 medium spiny neurons primary cultures. We demonstrated a key role of TRPC1 channels in supporting SOC pathway in HD neurons. We concluded that the TRPC1-mediated neuronal SOC pathway constitutes a novel target for HD treatment and that the identified compounds represent a novel class of therapeutic agents for treatment of HD and possibly other neurodegenerative disorders.     

From 4,5,6,7-tetrahydroindole to functionalized furan-2-one-4,5,6,7-tetrahydroindole-cyclobutene sequence in two steps

Ethyl 3-(4,5,6,7-tetrahydroindol-2-yl)propynoate, readily available from 4,5,6,7-tetrahydroindole and ethyl bromopropynoate, when treated with dichlorodicyanobenzoquinone (DDQ) in methanol affords furan-2-one-4,5,6,7-tetrahydroindole-cyclobutene sequence in a 52% yield. As kinetic and minor products, a furan-2-one isomer along with bicycloheptadienone have been either isolated or identified. The reaction has been shown to proceed via the isolable intermediate the [2+2]-cycloadduct of ethyl 3-(4,5,6,7-tetrahydroindol-2-yl)propynoate with DDQ. Other alcohols react with the [2+2]-cycloadduct in a similar way. The effect of the alcohol structure on the products ratio has been analyzed. All the intermediates and products are formed as single diastereomer, thus indicating a concerted character of the rearrangement.     

Synthesis of water and molecular oxygen highly enriched in <Superscript>17</Superscript>O and <Superscript>18</Superscript>O isotopes from carbon oxides

The reaction of carbon oxides and hydrogen in the presence of the Raney nickel catalyst has been used for water synthesis. A procedure has been developed for the recovery and collection of the synthesized water with minimal losses and without deteriorating the ¹⁷O or ¹⁸O isotope enrichment as compared to the initial CO₂ and CO. The recovery of oxygen with high concentrations of ¹⁷O and ¹⁸O isotopes is based on the reaction of xenon difluoride with water. The yield based on oxygen achieves 99% without reduction of isotope enrichment, which is confirmed by mass-spectral measurements of oxygen isotope concentrations in the initial reagents and final reaction products.     

Thiophosphorylation of Pharmacophoric Phenols,Diols, and Triols

Abstract

Novel organyldithiophosphonic and bis(aryldithiophosphonic) acids were obtained by the reaction of 2,4-diorganyl 1,3,2,4-dithiadiphosphetane-2,4-disulfides with paracetamol, 4-(1H-pyrrol-1-yl)phenol, ethambutol dihydrochloride, vitamin B₆, and its acetonide derivatives.     

On the approximation of solutions of stochastic differential inclusions

A sequence of approximating equations is constructed for stochastic differential inclusions, and the properties of the measures corresponding to solutions of the approximating equations are studied for the class of stochastic differential inclusions.Translated fromTeoriya Sluchaínykh Protsessov, Vol. 14, pp. 43–48, 1986.