1-Methyl-2,3-dihydro-1H-benzimidazole-2-selone

The title compound C8H8N2Se, is the product of the reaction of 2-chloro-1-methyl­benzimidazole with sodium hydro­selenide. The mol­ecule is almost planar (r.m.s. deviation = 0.041 Å) owing to the presence of the long chain of conjugated bonds (Se=C—NMe—C=C—C=C—C=C—NH). The C=Se bond length [1.838 (2) Å] corresponds well to those found in the close analogs and indicates its pronounced double-bond character. In the crystal, mol­ecules form helicoidal chains along the b axis by means of N—H⋯Se hydrogen bonds

1,3-Benzothia­zole-2(3H)-selone

The title compound, C7H5NSSe, is the product of the reaction of 2-chloro­benzothia­zole with sodium hydro­selenide. The mol­ecule is almost planar (r.m.s. deviation = 0.018 Å) owing to the presence of the long chain of conjugated bonds (Se=C—N—C=C—C=C—C=C). The geometrical parameters correspond well to those of the analog N-methyl­benzothia­zole-2(3H)-selone, demonstrating that the S atom does not take a significant role in the electron delocalization within the mol­ecule. In the crystal, mol­ecules form centrosymmetric dimers by means of inter­molecular N—H⋯Se hydrogen bonds. The dimers have a nonplanar ladder-like structure. Furthermore, the dimers are linked into ribbons propagating in [010] by weak attractive Se⋯S [3.7593 (4) Å] inter­actions

[Bis(pyridin-2-yl) selenide-κ2N,N′]tetrachloridotin(IV)

The title compound, [SnCl4(C10H8N2Se)], was obtained by the reaction of 2,2′-dipyridyl diselenide with tin tetrachloride. The SnIV ion is coordinated by two N atoms [Sn—N = 2.266 (2) and 2.274 (2) Å] from the bis(2-pyridyl)selenide ligand and four chloride anions [Sn—Cl = 2.3717 (6)–2.3939 (6) Å] in a distorted octahedral geometry. The central six-membered chelate ring has a boat conformation with the Se and Sn atoms deviating by 0.692 (3) and 0.855 (3) Å, respectively, from the mean plane through the remaining four ring atoms. The pyridine rings are inclined to each other by a dihedral angle of 49.62 (8)°. The crystal packing exhibits short intermolecular Se...Cl contacts [3.5417 (7) and 3.5648 (7) Å], weak C—H...Cl hydrogen bonds and π–π stacking interactions between the pyridine rings with a centroid–centroid distance of 3.683 (3) Å

Dichloridobis(pyridine-2-selenolato-κ2N,Se)tin(IV)

The title compound, [SnCl2(C5H4NSe)2], is the product of a reaction of 2,2′-dipyridyl diselenide with tin tetrachloride. The molecule is located about a twofold rotation axis. The coordination environment of the SnIV atom is a distorted octahedron, with two bidentate 2-pyridineselenolate ligands inclined to each other at an angle of 83.96 (7)°. The two Sn—Cl and two Sn—N bonds are in cis configurations, while the two Sn—Se bonds of 2.5917 (3) Å are in a trans configuration, with an Se—Sn—Se angle of 157.988 (15)°. In the crystal, π–π interactions between the pyridine rings [centroid-to-centroid distance of 3.758 (3) Å] and weak intermolecular C—H...Cl hydrogen bonds link the molecules into chains along the c axis

Bromination of bis(pyridin-2-yl) diselenide in methylene chloride: the reaction mechanism and crystal structures of 1H-pyridine-2-selenenyl dibromide and its cycloadduct with cyclopentene (3aSR,9aRS)-2,3,3a,9a-tetrahydro-1H-cyclopenta[4,5][1,3]selenazolo[3,2-a]pyridinium bromide

1H-Pyridine-2-selenenyl dibromide, C5H5NSeBr2, 1, is a product of the bromination of bis(pyridin-2-yl) diselenide in methylene chloride recrystallization from methanol. Compound 1 is essentially zwitterionic: the negative charge resides on the SeBr2 moiety and the positive charge is delocalized over the pyridinium fragment. The C—Se distance of 1.927 (3) Å is typical of a single bond. The virtually linear Br—Se—Br moiety of 178.428 (15)° has symmetrical geometry, with Se—Br bonds of 2.5761 (4) and 2.5920 (4) Å, and is twisted by 63.79 (8)° relative to the pyridinium plane. The Se atom forms an intermolecular Se...Br contact of 3.4326 (4) Å, adopting a distorted square-planar coordination. In the crystal, molecules of 1 are linked by intermolecular N—H...Br and C—H...Br hydrogen bonds, as well as by non-covalent Se...Br interactions, into a three-dimensional framework. (3aSR,(9aRS)-2,3,3a,9a-Tetrahydro-1H-cyclopenta[4,5][1,3]selenazolo[3,2-a]pyridinium-9 bromide, C10H12NSe+·Br−, 2, is a product of the cycloaddition reaction of 1 with cyclopentene. Compound 2 is a salt containing a selenazolopyridinium cation and a bromide anion. Both five-membered rings of the cation adopt envelope conformations. The dihedral angle between the basal planes of these rings is 62.45 (11)°. The Se atom of the cation forms two additional non-covalent interactions with the bromide anions at distances of 3.2715 (4) and 3.5683 (3) Å, attaining a distorted square-planar coordination. In the crystal, the cations and anions of 2 form centrosymmetric dimers by non-covalent Se...Br interactions. The dimers are linked by weak C—H...Br hydrogen bonds into double layers parallel to (001)

Novel cationic 1,2,4-selenadiazoles: synthesis via addition of 2-pyridylselenyl halides to unactivated nitriles, structures and four-center Se center dot center dot center dot N contacts (vol 50, pg 10689, 2021)

ISIC-G

Activation of Tissue Reparative Processes by Glow-Type Plasma Discharges as an Integral Part of the Therapy of Decubital Ulcers

The results of a clinical study of the complex treatment of pressure ulcers using the method of activation of reparative processes in tissues by cold plasma discharges initiated by high-frequency current are presented. Activation was carried out with a specialized device generating cold plasma discharges at frequencies of 0.11, 2.64, and 6.78 MHz. It was shown that the process of activation in the skin and muscle tissues of the bedsore zone proceeds most efficiently when using a current with a frequency of 6.78 MHz as compared to currents with a frequency of 2.64 and 0.11 MHz. For a needle electrode with a diameter of 0.3 mm, the optimal exposure parameters were power—(5.0 ± 1.5) W and time—(2.0–3.0) s. The results of the analysis of histological samples, histochemical, and bacteriological analysis confirmed the effect and showed the dynamics of the process of activation of reparative processes in the tissues of the bedsore wound under the influence of cold plasma discharges and a decrease in microbial contamination. The most pronounced effect of activation was formed during the period from 14 to 21 days. The effectiveness of therapy by the method of activation of reparative processes with cold plasma discharges, according to the criterion of the rate of wound healing, ranged from 14 to 16%, depending on the etiology of the decubitus wound. It is concluded that the activation of tissue reparative processes by glow-type plasma discharges as an integral part of the treatment of decubital ulcers is an effective link in the complex treatment of pressure sores