- Tuning the Optical Properties of Sulfonylaniline Derivatives: Degeneracy Breaking of Benzene Orbitals and Linkage through Nodal Planes
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The orbital degeneracy of benzene rings is resolved by an asymmetric push-pull system in 2,6-bis(methylsulfonyl)aniline (BMeSA), in which the highest occupied molecular orbital (HOMO) is located at the 4-position, while the lowest unoccupied molecular orbital (LUMO) is located at a different position and has a nodal plane through the carbon atoms at the 1- and 4-positions. Therefore, the π-extension of BMeSA at the 4-position reveals a strong overlap in the HOMO and a minimal overlap in the LUMO. Consequently, π-extended BMeSA derivatives exhibit longer absorbance and emission wavelengths in the order of the electron-donating abilities of their substituents at the 4-position, which is based on a decrease in an absolute HOMO-level-dependent HOMO-LUMO gap in accordance with the nodal arrangement. Positive fluorescent solvatochromism with polarity-dependent decrease in fluorescent intensity was also observed. The biaryls exhibited more planar geometries in the excited state than in the ground state. The charge transfer mechanism, which can be described as node-induced intramolecular charge transfer (NICT), differs from the planar intramolecular charge transfer (PICT) and twisted intramolecular charge transfer (TICT).
- Kudo, Shoh,Hoshino, Nanami,Beppu, Teruo,Katagiri, Hiroshi
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Read Online
- Antioxidant activity of two edible isothiocyanates: Sulforaphane and erucin is due to their thermal decomposition to sulfenic acids and methylsulfinyl radicals
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Sulforaphane (SFN) and erucin (ERN) are isothiocyanates (ITCs) bearing, respectively, methylsulfinyl and methylsulfanyl groups. Their chemopreventive and anticancer activity is attributed to ability to modulate cellular redox status due to induction of Phase 2 cytoprotective enzymes (indirect antioxidant action) but many attempts to connect the bioactivity of ITCs with their radical trapping activity failed. Both ITCs are evolved from their glucosinolates during food processing of Cruciferous vegetables, therefore, we studied antioxidant behaviour of SFN/ERN at elevated temperature in two lipid systems. Neither ERN nor SFN inhibit the oxidation of bulk linolenic acid (below 100 °C) but both ITCs increase oxidative stability of soy lecithin (above 150 °C). On the basis of GC-MS analysis we verified our preliminary hypothesis (Antioxidants 2020, 9, 1090) about participation of sulfenic acids and methylsulfinyl radicals as radical trapping agents responsible for the antioxidant effect of edible ITCs during thermal oxidation of lipids at elevated temperatures (above 140 °C).
- Cedrowski, Jakub,D?browa, Kajetan,Przybylski, Pawe?,Krogul-Sobczak, Agnieszka,Litwinienko, Grzegorz
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- Synthesis and reactivity of thiolate-bridged multi-iron complexes supported by cyclic (alkyl)(amino)carbene
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The combined utilization of Me2-cAAC (Me2-cAAC =:C(CH2)(CMe2)2N-2,6-iPr2C6H3) and thiolates as supporting ligands enables the access of unprecedented carbene coordinated thiolate-bridged diiron(ii) complexes [(Me2-cAAC)Fe(μ-SR)(Br)]2 (R = Me, 3; R = Et, 4). The coordination environment of each tetrahedral iron(ii) center in complexes 3 and 4 is composed of one terminal bromide atom, one carbene carbon atom and two thiolate sulfur atoms, which is similar to the carbide-containing sulfur-rich environment of iron centers in the belt region of the FeMo-cofactor. Interestingly, when NaSCPh3 was chosen as the thiolate ligand, C-S bond homolysis occurred to form a rare [3:1] site-differentiated cubane-type cluster [(Me2-cAAC)Fe4S4(Br)3][Me2-cAACH] (5). Furthermore, complexes 3 and 4 exhibit good exchange reactivity toward the azide anion to give novel thiolate-bridged diiron complexes with two azido ligands in a trans arrangement.
- Zhang, Yanpeng,Mei, Tao,Yang, Dawei,Zhang, Yixin,Wang, Baomin,Qu, Jingping
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p. 15888 - 15896
(2017/12/02)
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- METHOD FOR PRODUCING 1,2-BENZISOTHIAZOL-3-ONE COMPOUND
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The present invention provides a method for producing a 1,2-benzisothiazol-3-one compound by reacting a 2-(alkylthio)benzonitrile compound with a halogenating agent in the presence of water, wherein an alkyl halide that is generated as by-product is reacted with a sulfide to form an alkylthiol, which is converted into an alkali metal salt, and then the resulting alkali metal salt is reacted with a 2-halobenzonitrile compound to be converted into a 2-(alkylthio)benzonitrile compound and reused as a starting material for the production of a 1,2-benzisothiazol-3-one compound. By means of the present invention, it is possible to efficiently use the by-product that is generated during the production of a 1,2-benzisothiazol-3-one compound and economically produce a 1,2-benzisothiazol-3-one compound without placing a burden on the environment.
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Paragraph 0068; 0069; 0070
(2014/02/15)
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- USE OF 3-SUBSTITUTED THIOPHENES AS ODORANTS AND FLAVOURINGS
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The use is described of a compound of formula (I) wherein R represents a C1 - C4 alkyl or a C1 - C5 acyl residue as an odorant or flavouring or as a flavour enhancer.
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Page/Page column 13
(2008/06/13)
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- Process to prepare alkyl-ureas from O,S-dimethyl dithiocarbonate
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The present invention relates to the preparation of alkyl-ureas, starting from O,S-dimethyl dithiocarbonate, which provides the following steps: A) causing the O,S-dimethyl dithiocarbonate to react with a primary amine of general formula R1NH2in order to obtain an O-methyl thiocarbamate; B) isomerising the O-methyl thiocarbamate in order to obtain an S-methyl thiocarbamate; C) causing the S-methyl thiocarbamate with a compound of general formula R′R″NH, wherein R′ and R″ may be equal or different one in respect of the other and of R1and may be H, R2or R3, in order to obtain one of the alkyl-ureas of formula (4), (5) or (6).
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Page column 10
(2010/02/06)
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- Sulfur containing compounds
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This invention is directed to novel and known stufur containing compounds and pharmaceutically acceptable salts thereof that have utility as antifungals and as antiproliferative agents against mammalian cells, in particular cancer cells and most particularly leukemia-derived cells. The invention provides a method for synthesizing certain of the sulfur containing compounds that is more efficient than previously known methods.
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Page/Page column 26; 28; 29
(2010/11/30)
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- 4-phenyl-4-oxo-butanoic acid derivatives with kynurenine-3-hydroxylase inhibiting activity
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4-phenyl-4-oxo-butanoic acid derivatives for use in the treatment of the human or animal body by therepy; particularly as kynurenine-3-hydroxylase inhibitors, in the prevention and/or treatment of a neurodegenerative disease wherein the inhibition of such an enyzme is needed. The present invention further comprises a selected class of the above mentioned 4-phenyl-4-oxo-butanoic acid derivatives, their pharmaceutically acceptable salts, a process for their preparation and pharmaceutical compositions containing them.
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- Preparation and Characterisation of 2,2'-Bipyridine-4,4'-disulphonic and -5-sulphonic Acids and their Ruthenium(II) Complexes. Excited-state Properties and Excited-state Electron-transfer Reactions of Ruthenium(II) Complexes containing 2,2'-Bipyridine-4,4'-disulphonic Acid or 2,2'-Bipy..
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We report the syntheses of 2,2'-bipyridine-4,4'-disulphonic acid (H2bp-4,4'-ds) and 2,2'-bipyridine-5-sulphonic acid (Hbp-5-s), and several ruthenium(II) complexes derived therefrom, including 4-, 2- (bipy=2,2'-bipyridine), , and - and their 2,2'-bipyridine-4,4'-dicarboxylic acid (H2bpdc) analogues, viz. 4-, 2-, and .Some novel thioalkyl derivatives of 2,2'-bipyridine, including 4,4'-di(methylthio)-2,2'-bipyridine, 4,4'-di(ethylthio)-2,2'-bipyridine, and 4,4',6,6'-tetra(methylthio)-2,2'-bipyridine, were also prepared and characterised during the course of this investigation.The luminescent states of the complexes 4-, 2-, 4-, 2-, and were studied using variable-temperature lifetime measurements.Studies of the quenching of 2+>*, >*, 2->*, and 4->* by 1,1'-dimethyl-4,4'-bipyridinium bromide (methyl viologen) in aqueous solution as a function of ionic strength have demonstrated that the effects of charge in these electron-transfer reactions can be understood in terms of conventional theories of ionic reactions whilst, at the same time, confirming the effective charges of the ruthenium(II) complex ions.The rate constants for the quenching of 4->* and 2->* by copper(II) ions in neutral aqueous solution show unusual (non-Arrhenius) temperature dependences.A novel kinetic scheme involving parallel inner- and outer-sphere quenching mechanisms has been proposed to account for the observed behaviour.The luminescence decay of >* in the presence of aqueous copper(II) ions at pH 3.5 is non-exponential.This is interpreted in terms of a combination of static and dynamic quenching effects.
- Anderson, Susan,Constable, Edwin C.,Seddon, Kenneth R.,Turp, Janet E.,Baggott, James E.,Pilling, Michael J.
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p. 2247 - 2262
(2007/10/02)
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- Reactions of Co-ordinated Ligands. Part 32. The Reaction of Sulphur Nucleophiles with Cationic Molybdenum Alkyne Complexes: Alkyne Rotation and the Molecular Structures of the Complexes (η2-MeC2Me)(η-C5H5)> and 2-MeC2Me)(η-C5H5)>
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Treatment of 2(η2-MeC2Me)(η-C5H5)> with NaSR (R = Me, p-NH2C6H4, p-MeOC6H4, p-MeC6H4, C6H5, or p-NO2C6H4) leads to displacement of P(OMe)3 and formation of (η2-MeC2Me)(η-C5H5)>.Similar reactions afforded (η2-MeC2Me)(η-C5H5)> and (η2-ButC2H)(η-C5H5)>.Barriers to rotation of the but-2-yne ligand present in these complexes are related to electronic effects of the substituents on the thiolate ligand.The molecular structure of (η2-MeC2Me)(η-C5H5)> has been established by single-crystal X-ray crystallography.Crystals are monoclinic, space group P21/n with a = 8.968(3), b = 20.104(9), c = 11.452(5) Angstroem, β = 95.77(3), and Z = 4.Using 3601 reflections measured on a four-circle diffractometer at 200 deg K, the structure has been refined to R 0.028, R' 0.032.The molecule adopts the familiar three-legged piano stool geometry, in which the but-2-yne ligand is orientated such that the central C-C bond lies approximately parallel to the Mo-P vector.In contrast, 2-MeC2Me)2(η-C5H5)> reacts with NaSMe to give the complexes 2-MeC2Me)(η-C5H5)> and , whereas the corresponding reaction with 2-MeC2Me)2(η-C5H5)> affords 2-MeC2Me)(η-C5H5)>.Reaction of sodium dimethyldithiocarbamate with 1C2R2)2(η-C5H5)> (R1 = R2 = Me or R1 = But, R2 = H) gives the monoalkyne complexes 2-R1C2R2)(η-C5H5)>.In contrast the anion (1-) affords a separable mixture of 2-R1C2R2)2(η-C5H5)> and .Reaction of the S,S'-bidentate species with carbon monoxide gives 2-MeC2Me)(η-C5H5)>, which was structurally identified by X-ray crystallography.Crystals are orthorhombic, space group P212121 (no. 19) with Z = 4 in a unit cell of dimensions a = 9.852(3), b = 11.486(4), and c = 18.476(6) Angstroem.From 1714 independent intensities measured at 292 deg K the structure has been refined to R 0.059, R' 0.041.The molecule adopts a piano stool geometry with the but-2-yne lying parallel to the Mo-CO vector.The dithioaryl ligand is monodentate.
- Allen, Stephen R.,Glauert, Timothy H.,Green, Michael,Mead, Kevin A.,Norman, Nicholas C.,et al.
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p. 2747 - 2756
(2007/10/02)
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- Tetraphenylarsonium 1,2,3,4,5-Pentakis(methylmercapto)cyclopentadienide
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The title compound was prepared by reaction of stoichiometric amounts of sodium hydride, cyclopentadiene, and methyl disulfide in tetrahydrofuran.The title compound was characterized by NMR, IR, and cyclic voltammetry measurements.A three-dimensional crystal and molecular structure of has been determined by an X-ray diffraction study.The compound crystallizes in the centrosymmetric monoclinic space group P21/c 52h, No. 14> with a = 12.568 (2) Angstroem, b = 15.948(3) Angstroem, c = 17.523(3) Angstroem, β = 106.98 (1) deg, V = 3359.21 (10) Angstroem3, and ρcalcd = 1.342 g cm-3 for Z = 4.The structure was solved via the tangent formula and standard Fourier techniques and was refined by using full-matrix least-squares refinement to conventional discrepancy indices of RF = 8.65percent and RwF = 15.76percent for the 2652 independent data with ΔF/?(F0) 0 >= ?(Fo).All atoms with the exception of methyl hydrogens were located.The crystal consists of formula units of , cations and anions being separated by normal van der Waals distances, as are formula units from each other.All distances and angles within the tetraphenylarsonium cation are normal.The methylmercapto groups of the 1,2,3,4,5-pentakis(methylmercapto)cyclopentadienide anion have their configurations relative to the cyclopentadienyl ring fixed by packing forces within the crystal.Distances and angles within the cyclopentadienyl ring are normal.The S-C distances within the anion are reduced from the sum of the covalent radii for sulfur and sp2-hybridized carbon which may indicate the possibility of multiple bonding.
- Wudl, F.,Nalewajek, D.,Rotella, F. J.,Gebert, E.
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p. 5885 - 5890
(2007/10/02)
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- Quinones. Part 9. Side-chain Alkylthiolation of Methyl-1,4-naphthoquinones
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2-Methyl-1,4-naphthoquinones react with an excess of sodium methanethiolate to give methylthiomethyl derivatives.Corresponding products were obtained, but in lower yield, using α-toluene- and toluene-p-thiolates.With 3-chloro-2-methyl-1,4-naphthoquinone and methanethiolate, replacement of chlorine occurs before reaction with the side chain, while the minor products formed provide evidence that the side-chain alkylation proceeds by addition of thiolate to the tautomeric quinone methide form of the methylquinone.
- Thomson, Ronald H.,Worthington, Roger D.
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p. 282 - 288
(2007/10/02)
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- 6-N-Propyl-8-methoxymethyl or methylmercaptomethylergolines and related compounds
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6-n-Propyl (ethyl or allyl)-8β-methoxy-(methylsulfinyl, methylsulfonyl, or methylmercapto) methylergolines, 8-ergolenes or 9-ergolenes, useful as prolactin inhibitors and in the treatment of Parkinsonism.
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- 4-Nitro-5-cyanoimidazoles as coccidiostats
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4-Nitro-5-cyanoimidazoles substituted with a 1-loweralkyl group and variously substituted at the 2-position are useful as antiparasitic agents particularly as coccidiostats. The 4-nitro-5-cyanoimidazole coccidiostats are included in compositions useful for administration to poultry as treatment for coccidiosis.
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- 4-Methylthio-2-trifluoromethylmethanesulfonanilide and derivatives thereof
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2-(Trifluoromethyl)methanesulfonanilides substituted in the para position by methylthio, methylsulfinyl or methylsulfonyl groups and horticulturally acceptable salts thereof and composition containing these compounds are useful herbicides.
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