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Sulfoxide
Kinds of Sulfoxide Terms modified by Sulfoxide Selected AbstractsAsymmetric Cyclopropanation of Optically Active (1-Diethoxyphosphoryl)vinyl p -Tolyl Sulfoxide with Sulfur Ylides: A Rationale for DiastereoselectivityEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 4 2005Wanda H. Midura Abstract The title sulfoxide (S)-(+)- 1a was found to react with sulfur ylides affording the corresponding cyclopropanes in high yields. With fully deuterated dimethyl(oxo)sulfonium methylide, (CD3)2S(O)CD2, the cyclopropanation reaction occurred in a highly diastereoselective manner producing the cyclopropane 4a - d2 as a major diastereomer in which the newly formed quaternary ,-carbon atom is chiral due to isotopic substitution (CH2 vs. CD2). The diastereomer 4b - d2, having the opposite configuration at the ,-carbon atom, was obtained starting form the 2,2-dideuterio substituted vinyl sulfoxide, (S)-(+)- 1a - d2, and the nondeuterated ylide. The diastereomeric ratio in both reactions was found to be ca. 10:1. The reaction of (S)-(+)- 1a with diphenylsulfonium isopropylide yielded the cyclopropane (+)- 7 as a single diastereomer. X-ray structural studies of the crystalline 1-phosphorylvinyl sulfoxide 9 as well as density functional calculations (B3LYP/6-31G*) on (1-phosphoryl)vinyl sulfoxides revealed the origin of the experimentally observed diastereoselectivities and allowed us to propose a transition state model for the cyclopropanation reaction of chiral 1-phosphorylvinyl sulfoxides. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] Agarose Sols and Gels RevisitedMACROMOLECULAR SYMPOSIA, Issue 1 2006Jean-Michel Guenet Abstract Agarose sols have been seen for long as solutions of flexible chains that, on cooling, produce thermoreversible gels through double-helix formation. Investigations of the chain conformation in the sol state by small-angle neutron scattering reveals instead a rigid chain with a very large persistence length (lp,>,9 nm). The chain cross-section radius and mass per unit length correspond to characteristics of helices as those described by Foord and Atkins. These results lead one to a reappraisal of the occurrence of double helices in the gelation process, as they rather suggest a transition of the type loose-single helix,tight single helix. Studies of gels from agarose/water/cosolvent where the cosolvent is Dimethyl Sulfoxide (DMSO), Dimethyl Formamide (DMF), and Methyl Formamide (MF) have led one to conclude on the formation of agarose/water/ cosolvent ternary complexes. The contrast variation method by neutron scattering gives further support to this assumption. Finally, determination of the gel nanostructure allows one to account for the two regimes observed for the variation of the elastic modulus vs concentration. [source] Transient Osmotic Absorption of Fluid in Microvessels Exposed to Low Concentrations of Dimethyl SulfoxideMICROCIRCULATION, Issue 1 2006CATHERINE A. GLASS ABSTRACT Dimethyl Sulfoxide (DMSO) is a common solvent for pharmacological agents. It is a small, lipophilic molecule thought to be relatively highly permeable through the cell membrane. While measuring the effect of low concentrations of DMSO (0.05,0.5% v/v) on capillary hydraulic conductivity as a vehicle control for pharmacological agents, the authors noticed what appeared to be an unusual transient absorption of fluid across the vessel wall. This absorption occurred during occlusion of the vessel, but dissipated quickly (1.7,8.6 s). The transient reabsorption reappeared upon each successive occlusion. To determine the nature of this transient absorption, the authors have measured the effect of increasing the pressure of the perfusing solution, of the concentration and time of perfusion of DMSO, and of superfusing the DMSO. They found that the absorption rate, but not the filtration rate, was concentration dependent, and was significantly correlated with the osmotic pressure of the DMSO. Moreover, the time taken for completion of the transient, i.e., time to reversal of flow, was inversely proportional to the hydraulic conductivity of the vessel. Furthermore, the transient absorption could be reduced and eventually abolished by increasing the hydrostatic pressure. These results strongly suggested that perfusion with low concentrations of DMSO could set up a significant osmotic pressure gradient across the vessel wall. This proposed mechanism for the absorption was confirmed by the measurement of a significant osmotic reflection coefficient of the vessel wall to DMSO (0.11 ± 0.01). Relatively low concentrations (0.05,0.5%) of DMSO were therefore able to stimulate a significant osmotic transient across the blood vessel walls. [source] S -Allyl- L -Cysteine Sulfoxide Inhibits Tumor Necrosis Factor-Alpha Induced Monocyte Adhesion and Intercellular Cell Adhesion Molecule-1 Expression in Human Umbilical Vein Endothelial CellsTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 3 2010Chai Hui Abstract Garlic and its water-soluble allyl sulfur-containing compound, S -Allyl- L -cysteine Sulfoxide (ACSO), have shown antioxidant and anti-inflammatory activities, inhibiting the development of atherosclerosis. However, little is known about the mechanism(s) underlying the therapeutic effect of ACSO in inhibiting the formation of atherosclerostic lesion. This study aimed to investigate whether ACSO could modulate tumor necrosis factor-alpha (TNF-,)-induced expression of intercellular cell adhesion molecule-1, monocyte adhesion and TNF-,-mediated signaling in human umbilical vein endothelial cells. While TNF-, promoted the intercellular cell adhesion molecule-1 mRNA transcription in a dose- and time-dependent manner, ACSO treatment significantly reduced the levels of TNF-,-induced intercellular cell adhesion molecule-1 mRNA transcripts (P < 0.01). Furthermore, ACSO dramatically inhibited TNF-, triggered adhesion of THP-1 monocytes to endothelial cells and porcine coronary artery rings. Moreover, ACSO mitigated TNF-, induced depolarization of mitochondrial membrane potential and overproduction of superoxide anion, associated with the inhibition of NOX4, a subunit of nicotinamide adenine dinucleotide phosphate-oxidase, mRNA transcription. In addition, ACSO also inhibited TNF-,-induced phosphorylation of JNK, ERK1/2 and I,B, but not p38. Apparently, ACSO inhibited proinflammatory cytokine-induced adhesion of monocytes to endothelial cells by inhibiting the mitogen-activated protein kinase signaling and related intercellular cell adhesion molecule-1 expression, maintaining mitochondrial membrane potential, and suppressing the overproduction of superoxide anion in endothelial cells. Therefore, our findings may provide new insights into ACSO on controlling TNF-,-mediated inflammation and vascular disease. Anat Rec, 2010. © 2010 Wiley-Liss, Inc. [source] ChemInform Abstract: Synthesis of Conjugated Enynes by Assembly of Three Components, Ketones, Chloromethyl p-Tolyl Sulfoxide, and Acetylenes, with the Magnesium Carbenoid 1,2-CC Insertion as the Key Reaction.CHEMINFORM, Issue 18 2010Hideki Saitoh Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Double Michael Addition of Dithiols to Acetylenic Carbonyl Compounds under the Influence of Molecular Sieve and Dimethyl Sulfoxide.CHEMINFORM, Issue 17 2010Tomoko Kakinuma Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Chemoselective Etherification of Benzyl Alcohols Using 2,4,6-Trichloro-1,3,5-triazine and Methanol or Ethanol Catalyzed by Dimethyl Sulfoxide.CHEMINFORM, Issue 11 2009Lili Sun Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Nucleophilic (Phenylsulfinyl)difluoromethylation of Carbonyl Compounds with Difluoromethyl Phenyl Sulfoxide.CHEMINFORM, Issue 6 2008Lingui Zhu Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: A New Synthesis of ,,,-Unsaturated Esters from Three Components, Aldehydes, Chloromethyl p-Tolyl Sulfoxide, and tert-Butyl Acetate, via Magnesium Carbenoid 1,2-CH and 1,2-CC Insertion as the Key Reaction.CHEMINFORM, Issue 2 2008Tsuyoshi Satoh Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Dimethyl Sulfoxide Mediated Elimination Reactions in 3-Aryl 2,3-Dihalopropanoates: Scope and Mechanistic Insights.CHEMINFORM, Issue 50 2007Wei Li Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Synthesis of Tetracene Sulfoxide and Tetracene Sulfone via a Cascade Cyclization Reaction.CHEMINFORM, Issue 40 2007Yi-Chun Lin Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] A New Process for the Synthesis of Aurones by Using Mercury (II) Acetate in Pyridine and Cupric Bromide in Dimethyl Sulfoxide.CHEMINFORM, Issue 39 2006Nitin N. Agrawal Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Diastereoselective Ni(0)-Catalyzed Carbocyclization to Chiral Vinylic Sulfoxide.CHEMINFORM, Issue 51 2005Naoyoshi Maezaki Abstract For Abstract see ChemInform Abstract in Full Text. [source] The Deoxygenation of Sulfoxide Mediated by the Ph3P/Lewis Acid Combination and the Application to the Kinetic Resolution of Racemic Phosphines Using Optically Active Sulfoxide.CHEMINFORM, Issue 33 2005Satoshi Kikuchi Abstract For Abstract see ChemInform Abstract in Full Text. [source] Synthesis of 2-Benzyl-1,10-phenanthrolines Substituted by Sulfoxide or Sulfone Groups as Potential Photochromic Compounds.CHEMINFORM, Issue 3 2003Arnault Heynderickx Abstract For Abstract see ChemInform Abstract in Full Text. [source] ChemInform Abstract: A New Method for Synthesis of Allenes, Including an Optically Active Form, from Aldehydes and Alkenyl Aryl Sulfoxides by Sulfoxide,Metal Exchange as the Key Reaction and an Application to a Total Synthesis of Male Bean Weevil Sex Attractant (XXV).CHEMINFORM, Issue 32 2002Tsuyoshi Satoh Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Optimum Conformational Flexibility of Subtilisin to Maximize the Enantioselectivity for Subtilisin-Catalyzed Transesterification in an Organic Solvent with an Addition of Dimethyl Sulfoxide.CHEMINFORM, Issue 44 2001Keiichi Watanabe Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Structure and Dynamics of Water Confined in Dimethyl SulfoxideCHEMPHYSCHEM, Issue 1 2006A. Wulf Abstract We study the structure and dynamics of hydrogen-bonded complexes of H2O/D2O and dimethyl sulfoxide (DMSO) by infrared spectroscopy, NMR spectroscopy and ab initio calculations. We find that single water molecules occur in two configurations. For one half of the water monomers both OH/OD groups form strong hydrogen bonds to DMSO molecules, whereas for the other half only one of the two OH/OD groups is hydrogen-bonded to a solvent molecule. The H-bond strength between water and DMSO is in the order of that in bulk water. NMR deuteron relaxation rates and calculated deuteron quadrupole coupling constants yield rotational correlation times of water. The molecular reorientation of water monomers in DMSO is two-and-a-half times slower than in bulk water. This result can be explained by local structure behavior. [source] Electroenzymatic Synthesis of Chiral SulfoxidesENGINEERING IN LIFE SCIENCES (ELECTRONIC), Issue 2 2006C. Kohlmann Abstract Chloroperoxidase (CPO) from Caldariomyces fumago (E.C.,1.11.1.10) is able to enantioselectively oxidize various sulfides to the corresponding (R)-enantiomer of the sulfoxides. For these oxidations the enzyme requires an oxidant. Most commonly, tert -butyl hydroperoxide (TBHP) and hydrogen peroxide are used. As it is known that these oxidants inactivate the enzyme, the enzymatic reaction was combined with the electrochemical in situ generation of hydrogen peroxide. As substrates for this combination of an enzymatic and an electrochemical reaction methyl p-tolyl sulfide, 1-methoxy-4-(methylthio)benzene and N-MOC- L -methionine methyl ester were used to carry out batch experiments. [source] Aromatic and Benzylic C,H Bond Functionalization Upon Reaction between Nitriles and Perfluoroalkyl SulfoxidesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 31 2009Yohan Macé Abstract We studied the thermal behavior of some intermediates formed by reaction of nitriles with perfluoroalkyl sulfoxides upon trifluoromethanesulfonic anhydride activation. Bistriflate ketal 3, precursor of sulfilimine 1, may undergo a rearrangement to sulfanyl nitrile 5 after triflic acid elimination under thermal conditions. With p -tolyl trifluoromethyl sulfoxide, remote triflic acid elimination from intermediate 4 leads to benzamide 8 formation. These reactions involve, respectively, selective functionalization of the aromatic ortho C,H bond or the benzylic C,H bond para to the sulfoxide group. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Sulfilimines and Sulfoximines by Reaction of Nitriles with Perfluoroalkyl SulfoxidesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 19 2009Yohan Macé Abstract The species obtained by activation of perfluoroalkylated sulfoxides with trifluoromethanesulfonic anhydride behaves as highly electrophilic entities. Their reaction with nitriles allows a Ritter-like process leading to the new fluorinated acylsulfilimines 1,21 after hydrolysis. This flexible methodology allows some variation of both the sulfoxide and nitrile components. Derived acylsulfoximines 22,25 or free sulfoximines 26,28 could be selectively obtained, as needed, by further controlled oxidation with the cheap and nontoxic potassium permanganate. This oxidation may be performed either after isolation of the intermediate sulfilimine, or more conveniently in a one-pot process directly from fluorinated sulfoxides. This versatile, solvent and metal free, reaction is thus an opening way through the synthesis of new ligands or electrophilic trifluoromethylating reagents.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Diastereoselective Synthesis of -Hydroxy Sulfoxides: Enzymatic and Biomimetic ApproachesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 2 2007Stefano Colonna Abstract Stereoselectivities of up to 98,% have been found in the enzymatic synthesis of ,-hydroxy sulfoxides catalyzed by cyclohexanone monooxygenase (CHMO). The diastereoselectivity of the "one-pot" preparation of the title compounds in the presence of bovine serum albumin has also been investigated. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Applications of Catalytic Asymmetric Sulfide Oxidations to the Syntheses of Biologically Active SulfoxidesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 1 2005Julien Legros Abstract Optically active sulfoxides are important compounds for medicinal and pharmaceutical chemistry. Driven by the increasing demand for efficient, selective and environmentally friendly industrial processes, several catalytic methodologies have been developed in recent years for the stereoselective oxidation of sulfides for the preparation of biologically active sulfoxides. Both small-scale approaches to the problem as well as some large-scale applications that are already in industrial use are described in this review. [source] ChemInform Abstract: Guanidinium Nitrate/Silica Sulfuric Acid/Ammonium Bromide as an Effective, Viable and Metal-Free Catalytic Media for the Selective Oxidation of Sulfides to the Sulfoxides.CHEMINFORM, Issue 19 2010Mohsen Nikoorazm Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: o-Nitrophenyl Sulfoxides: Efficient Precursors for the Mild Preparation of Alkenes.CHEMINFORM, Issue 18 2010Xiao Lu Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Highly Efficient and Chemoselective Reduction of Sulfoxides Using the System Silane/Oxo-Rhenium Complexes.CHEMINFORM, Issue 11 2010Sara C. A. Sousa Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Rapid and Mild Deoxygenation of Sulfoxides with MoCl5/Gallium System under Ultrasonication.CHEMINFORM, Issue 7 2010Byung Woo Yoo Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Iron(II) Triflate as an Efficient Catalyst for the Imination of Sulfoxides.CHEMINFORM, Issue 44 2009Olga Garcia Mancheno Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Gold Catalysis and Chiral Sulfoxides: Enantioselective Synthesis of Dihydroisoindol-4-ols.CHEMINFORM, Issue 7 2009A. Stephen K. Hashmi Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: An Asymmetric Synthesis of Esters and ,-Lactones with Simultaneous Construction of Vicinal Stereogenic Carbons at the ,- and ,-Position Starting from Optically Active 1-Chlorovinyl p-Tolyl Sulfoxides.CHEMINFORM, Issue 37 2008Shimpei Sugiyama Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] | ||||||||||||||||||||||||||||||||||||||||