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A convenient synthesis of new 8-oxa-2-azaspiro[4.5]decane from commercially available reagents based on tetrahydropyran-4-carbonitrile and 1-bromo-2-fluoroethane has been developed. This compound is promising for the production of important biologically active compounds. [ABSTRACT FROM AUTHOR]

Investigations of bromination of naphtho[2,3-c][1,2,5]thiadiazole-4,9-dione revealed that the reaction proceeded most efficiently with N-bromosuccinimide in sulfuric acid and depending on the reaction conditions, can give mono-, di-, tri- and tetrabromo derivatives of naphtho[2,3-c][1,2,5]thiadiazole-4,9-dione. A series of the major isomers was isolated, and their structure was proven using heteronuclear multiple bond correlation NMR spectroscopy and high-resolution mass spectrometry. [ABSTRACT FROM AUTHOR]

Two new dyes were obtained; their D—A—π—A′ structure included benzo[d][1,2,3]-thiadiazole as an internal acceptor (A), a cyanoacrylic acid residue as a terminal anchor acceptor (A′), a 4H-cyclopenta[2,1-b:3,4-b′]dithiophene π-spacer with branched alkyl groups, and 2,3-dihydroindole condensed with carbocycles as a donor. The optical and electrochemical characteristics of the obtained dyes were determined, and solar cells based on them were assembled. The power conversion efficiency reached 3.05% for a device based on the dye containing a 2,3,4,4a,9,9a-hexahydro-1H-carbazole donor moiety. The relatively low value of photovoltaic efficiency is likely due to excessive steric effects that are demonstrated by the branched alkyl groups when the dyes are sorbed onto the TiO2 surface, which leads to an insufficient concentration of the dye on the electrode surface, resulting in a decrease in the quantity of absorbed photons. [ABSTRACT FROM AUTHOR]

Cyclization of 3,4-diaminopyridine-2,5-dicarbonitrile with thionyl chloride and selenium dioxide afforded [1,2,5]thia- and [1,2,5]selenadiazolo[3,4-c]pyridine-4,7-dicarbonitrile, respectively. Both compounds were electrochemically reduced to the corresponding radical anions. [ABSTRACT FROM AUTHOR]

Dyes of various structural complexity, based on the fragments of 4-(2-ethylhexyl)-1,2,3,3a,4,8b-hexahydrocyclopenta[b]indole and cyanoacrylic acid, were obtained. Solar cells sensitized with these dyes were developed, and their key photophysical characteristics were determined. The power conversion efficiency reached 4.64% for the most optimal devices based on a dye with an average structural complexity containing donor and acceptor fragments linked via a thiophene bridge. This value is comparable to the values obtained in the case of solar cells based on dyes of more complex structural types. [ABSTRACT FROM AUTHOR]

Review: 97 refs. [ABSTRACT FROM AUTHOR]

Benzo- and pyridoannulated 1,2-dithiole-3-thiones react with compounds containing an activated methyl group such as 1-methyl-3,4-dihydropyrrolo[1,2- a]pyrazine and 2-methylpyridines to furnish substituted 1,2-dithiol-3-ylidenes. [ABSTRACT FROM AUTHOR]

Data on the synthesis and reactions of 1,3,2-dithiazoles over the last 30 years are reviewed and classified. [ABSTRACT FROM AUTHOR]

Nucleophilic substitution of the chlorine atom in 4,5-dichloro-1,2-dithiol-3-one using 1-thio-β-d-glucopyranose and its 2,3,4,6-tetra-O-acetyl derivative in acetonitrile resulted in two new 5-thioglucoside conjugates of 4-chloro-1,2-dithiol-3-one. The obtained thioglucosides showed cancer-preventive properties in a model of mouse epidermal JB6Cl41 P+ cells in soft agar, while one of them manifested antitumor activity in in vivo experiments in CD1 mice on a model of solid Ehrlich carcinoma. Both compounds were shown to inhibit basic AP-1-dependent transcriptional activity in murine JB6 Cl41 luc-AP-1 cells. [ABSTRACT FROM AUTHOR]

Nucleophilic substitution of a chlorine atom in 4,5 dichloro-1,2-dithiole-3-thione with per-O-acetyl-1-mercaptho derivatives of d-glucose, d-galactose, d-mannose, d-xylose, l-arabinose, and d-maltose gave six new acetylthioglycoside conjugates of 4-chloro-1,2-dithiole-3-thione. These thioglycosides were shown to possess cancer preventive activity on the models of JB6 Cl41 P+ mouse epidermal cells and THP-1 human leukemia cells in soft agar, as well as to inhibit the AP-1-dependent transcriptional activity in JB6 Cl41 luc-AP-1 cells, which suggests the possibility of using the new compounds as potential cancer preventive drugs. [ABSTRACT FROM AUTHOR]

The reaction of 4,7-dibromo[1,2,5]thiadiazolo[3,4-d]pyridazine with alcohols and sodium alkoxides was evaluated under various conditions. Depending on the reaction conditions, either alkoxy or hydroxy derivatives of [1,2,5]thiadiazolo[3,4-d]pyridazine can be obtained. 4,7-Di-(dodecyloxy)- and 4,7-di(hexyloxy)[1,2,5]thiadiazolo[3,4-d]pyridazines, which may be of interest as the compounds exhibiting liquid crystalline properties, were synthesized for the first time. [ABSTRACT FROM AUTHOR]

Treatment of 4-phenyl-5H-1,2,3-dithiazole-5-thione with iodine in acetonitrile yielded crystalline product with thione-iodonium three-center halogen bond and triiodide anion bound with two iodine molecules by the typical halogen bonds. At the level of a theoretical study of electron density and its gradients, the similarity of electronic properties of the central iodine atom in bridged moiety [S−I−S]+ and in triiodide anion [I−I−I]− has been illustrated. The experimental and theoretical Raman spectra of iodonium salt are discussed: the assignment of the bands corresponding to the iodonium bridged fragment vibrations has been made on the basis of calculated ab initio data. [ABSTRACT FROM AUTHOR]

The oxidation of hexane-2,3,4,5-tetraone tetraoxime with dinitrogen tetroxide was studied in different solvents. The primary furoxan ring closure was found to occur involving either two central or two terminal oxime groups to form 4,7-dimethyl[1,2,5]oxadiazolo[3,4-d]pyridazine 1,5,6-trioxide and the previously unknown 4,4′-dimethyl-[3,3′-bi(1,2,5-oxadiazole)] 5,5′-dioxide. The structure of the latter compound was established by X-ray diffraction. [ABSTRACT FROM AUTHOR]

A convenient one-pot synthesis of nitro derivatives of 2,1,3-benzothiadiazole 1-oxides by the reaction of o-nitroanilines with sulfur monochloride was developed. The structural features of 4-nitrobenzothiadiazole and its N-oxide were considered. High in vitro release of nitric oxide (69%) was found for a 6-nitro-2,1,3-benzothiadiazole sample by the Griess assay, which indicated good prospects for this class of compounds. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented regarding the reaction of 3H-1,2-dithiol-3-imines 1 with isonitriles 2.

The article discusses a research based on the synthesis of thiete-2-thione by the reaction of 1, 2-dithiole-3-thione with a number of sulfur-abstracting agents. It mentions that the reaction proceeds rapidly with sodium cyanide and triphenylphosphine at room temperature, and it is also accompanied by deep resinification. It also includes that the use of trimethyl phosphite in acetonitrile indicates optimum conditions, affording thiete-2-thione in 92 percent yield of the product.

A versatile one-pot synthesis of 4-substituted 3-(nitrooxyalkyl)furoxans by the reaction of 3-alkylfuroxans with a mixture of nitric and sulfuric acids was developed. A plausible mechanism of this unusual transformation was explained in terms of a new Grob-type fragmentation. [ABSTRACT FROM AUTHOR]

One-pot synthesis of 3-chloro-1,2,5-thiadiazoles from monosubstituted glyoximes and sulfur monochloride was developed. [ABSTRACT FROM AUTHOR]

The study concerns molecular design and theoretical study of novel prospective organic sensitizers based on D–A–π–A concept. A modification of the concept (DA–π–A) and new ways for design of organic sensitizers are proposed. The study shows that π-block plays a key role for the wavelength shift in UV-Vis spectra. An existence of element of higher periods in the π-block provides a noticeable bathochromic shift. The thienyl bridge in A-block provides a red shift with respect to phenyl bridge for [1,2,5]oxadiazolo[3,4-c]pyridines while the phenyl bridge provides a red shift with respect to thienyl bridge for [1,2,5]selenadiazolo[3,4-c]pyridines. The maximal wavelengths are observed for DA-blocks with aliphatic/alicyclic fragments we proposed. An influence of enthalpy of formation and polarity of DA-blocks on bathochromic shift is shown. The quantitative dependencies of wavelengths on the enthalpies and dipole moments are determined. The maximal oscillator strengths are observed for the planar DA-block. Therefore, the conditions for design of compounds possessing the maximal wavelengths and oscillator strengths are different: the latter presupposes the planar structure of DA-block while the first presupposes an existence of nonplanar aliphatic/alicyclic fragments. Thus, the further design of organic sensitizers should include some combination of these concepts. [ABSTRACT FROM AUTHOR]

number of 5-(1,2,5-oxadiazol-3-yl)-1 H-tetrazoles were obtained in high yields by reactions of 3-cyano-1,2,5-oxadiazoles with sodium azide or by nitrosation of furazan-based amidrazones, which are easily prepared from the same starting reagents. [ABSTRACT FROM AUTHOR]

A number of 3-methyl-4-(5-R-1 H-1,2,4-triazol-3-yl)-1,2,5-oxadiazoles were obtained in high yields by thermal dehydration of acylated 4-methyl-1,2,5-oxadiazole-3-carboxamide hydrazones. [ABSTRACT FROM AUTHOR]

The article discusses a study regarding the reactions of 1,2,5-oxadiazoles synthesized with sulfur monochloride as a heterocyclic material. The study uses various methods which include nuclear magnetic resonance (NMR) spectroscopy, elemental analysis, and mass spectroscopy. Result shows that N-ethyl and N-isopropyl groups can interact with sulfur monochloride.