- Influence of Lewis acid charge and proximity in MoMo?M linear chain compounds with M = Na+, Ca2+, Sr2+, and Y3+
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The syntheses, X-ray structural characterizations, and electrochemical properties of four new paddlewheel [MMo2(SNO5)4Cl](n-1)+ (Mn+ = Na+, Ca2+, Sr2+, Y3+; HSNO5 = monothiosuccinimide) compounds are described here. By changing the Mn+ cation charge and size, we demonstrate a method for easily tuning the Lewis acidity of the MoMo quadruple bond and the [Mo2]4+/5+ redox potential. As the charge of the Mn+ cation is increased, the distal Mo atom becomes more Lewis acidic, leading to a shorter Mo2-Cl bond distance, and the [Mo2]4+/5+ redox couple becomes less accessible. As the Mn+ Mo2 distance is increased, the distal Mo atom becomes less Lewis acidic, leading to a longer Mo2-Cl bond distance.
- Dolinar, Brian S.,Berry, John F.
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- Lewis acid enhanced axial ligation of [Mo2]4+ complexes
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We report here the syntheses, X-ray crystal structures, electrochemistry, and density functional theory (DFT) single-point calculations of three new complexes: tetrakis(monothiosuccinimidato)dimolybdenum(II) [Mo 2(SNO5)4, 1a], tetrakis(6-thioxo-2-piperidinonato) dimolybdenum(II) [Mo2(SNO6)4, 1b], and chlorotetrakis(monothiosuccinimidato)pyridinelithiumdimolybdenum(II) [pyLiMo2(SNO5)4Cl, 2-py]. X-ray crystallography shows unusually short axial Mo2-Cl bond lengths in 2-py, 2.6533(6) A, and dimeric 2-dim, 2.644(1) A, which we propose result from an increased Lewis acidity of the Mo2 unit in the presence of the proximal Li + ion. When 2-py is dissolved in MeCN, the lithium reversibly dissociates, forming an equilibrium mixture of (MeCNLiMo2(SNO5) 4Cl) (2-MeCN) and [Li(MeCN)4]+[Mo 2(SNO5)4Cl]- (3). Cyclic voltammetry was used to determine the equilibrium lithium binding constant (room temperature, K eq = 95 ± 1). From analysis of the temperature dependence of the equilibrium constant, thermodynamic parameters for the formation of 2-MeCN from 3 (ΔH = -6.96 ± 0.93 kJ mol-1 and ΔS = 13.9 ± 3.5 J mol-1 K-1) were extracted. DFT calculations indicate that Li+ affects the Mo-Cl bond length through polarization of metal-metal bonding/antibonding molecular orbitals when lithium and chloride are added to the dimolybdenum core.
- Dolinar, Brian S.,Berry, John F.
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p. 4658 - 4667
(2013/05/22)
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- ARYLOXY-SUBSTITUTED BENZIMIDAZOLE DERIVATIVES
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A glucokinase activator is provided; and a treatment and/or a preventive for diabetes, or a treatment and/or a preventive for diabetes such as retinopathy, nephropathy, neurosis, ischemic cardiopathy, arteriosclerosis, and further a treatment and/or a preventive for obesity are provided. The invention relates to a compound of a formula (I): [wherein R1 and R2 represent a hydrogen, etc.; R3 represents a hydrogen atom, a halogen atom, etc.; R4 each independently represents a hydrogen atom, a lower alkyl group, etc.; Q represents a carbon atom, a nitrogen atom or a sulfur atom (the sulfur atom may be mono- or di-substituted with an oxo group); R5 and R6 each represent a hydrogen atom, a lower alkyl group, etc.; X1, X2, X3 and X4 each independently represent a carbon atom or a nitrogen atom; Z represents an oxygen atom, a sulfur atom or a nitrogen atom; Ar represents an aryl or heteroaryl group optionally mono to tri-substituted with a group selected from the substituent group β; ring A represents a 5- or 6-membered nitrogen-containing heteroaromatic group; m indicates an integer of from 1 to 6; n indicates an integer of from 0 to 3; p indicates an integer of from 0 to 2 (provided that at least two of X1 to X4 are carbon atoms); q indicates 0 or 1] or its pharmaceutically-acceptable salt, which has an effect of glucokinase activation and is useful as a treatment for diabetes.
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Page/Page column 39-40
(2010/11/28)
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- PHOTOREACTION OF 1- AND 3-ARALKYL ALICYCLIC THIOIMIDES: FACILE SYNTHESES OF VARIOUS AZABICYCLOALKANES VIA NORRISH TYPE II PROCESS
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Photolysis of the 1-(ω-aralkyl)cyclic thioimides (1 b,e,g,h) gave a pair of stereoisomers of 1-azabicycloalkanes (2, 3) in moderate yields.Similarly, in 3-(ω-phenylalkyl)cyclic thioimides (5a-e), a pair of stereoisomers of 2-azabicycloalkanes (6, 7) were
- Oda, Kazuaki,Fukuzawa, Yuichi,Ohno, Kosei,Machida, Minoru,Kanaoka, Yuichi
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- Synthesis and Characterization of Monothiosuccinimides
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The synthesis and characterization are described of a series of monothiosuccinimides.These imides are potentially valuable synthetic intermediates, particularly for the preparation of a bile pigments.Also described are the synthesis and unusual chemical and spectral behavior of a monothiomaleimide derivative, whose X-ray crystallographic structure was determined.
- Bishop, John E.,Dagam, Shekhar A.,Rapoport, Henry
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p. 1876 - 1883
(2007/10/02)
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- STUDIES ON ORGANOPHOSPHORUS COMPOUNDS XLVII PREPARATION OF THIATED SYNTHONS OF AMIDES, LACTAMS AND IMIDES BY USE OF SOME NEW P,S-CONTAINING REAGENTS
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The thionation properties of 2,4-bismethylthio-1,3,2,4-dithiadiphosphetane 2,4-disulfide, 1, 2,4-bis(4-phenoxyphenyl)-1,3,2,4-dithiaphosphetane 2,4-disulfide, 2, 2,4-bis(4-phenylthiophenyl)-1,3,2,4-dithiaphosphetane 2,4-disulfide, 3, and 2,4-bis(4-methoxyphenyl)-1,3,2,4-dithiaphosphetane 2,4-disulfide (LR), 4, have been investigated on a series of amides, lactams and imides.The most remarkable feature is that 2, 3 and 4 thionate most amides and lactams in THF at room temperature (reaction time 5 min) to give the corresponding thionated compounds.Imides are easily thionated by 2, 3 and 4 in DME at 60 oC.The reactions of 1 with amides, imides and most lactams are run at 60 oC to give good yields of the corresponding thionated compounds.
- Yde, B.,Yousif, N. M.,Pedersen, U.,Thomsen, I.,Lawesson, S. -O.
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p. 2047 - 2052
(2007/10/02)
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- Diazaestrones and analogs. I. Pharmacological study and synthesis of heterosteroid analogs to establish structure-analgesic activity relationships
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With the intention of showing the effect, about pharmacological properties, in replacing two estron asymetric carbon by nitrogen atoms and removal of angular methyl from steroid, stereospecific synthesis of 8,13-diazaestron and several substituted similar compounds was realized from β-1-(succinimidoethyl)-dihydroisoquinolines, precursors of a C open ring synthesis. The splitting of the 2-methoxydiazaestron methyl ester was carried out by mean of binaphthylphosphoric acid, and synthesis of several modified analogs of heterosteroid, was carried out to determine the effect of aromatic ring reduction, lactamic carbonyl reduction, and distance between 8 and 13 nitrogen atoms, about pharmacological activity. Hormonal, spasmolytic and analgesic activities were studied, good results were observed in analgesic activity.
- Hocquaux,Marcot,Redeuilh,et al.
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p. 319 - 329
(2007/10/02)
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