- Palladium-Catalyzed Decarboxylative Asymmetric Allylic Alkylation of Thietane 1,1-Dioxides
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A palladium-catalyzed decarboxylative asymmetric allylic alkylation of thietane 1,1-dioxides via linear enolate intermediates from racemic starting materials has been developed. This process installs an α-sulfonyl tetrasubstituted stereogenic center with high enantioselectivity. The potential to transform the alkylated products to novel types of enantioenriched spirocycles for medicinal chemistry applications has also been demonstrated.
- Laidlaw, Gillian,Franckevi?ius, Vilius
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supporting information
p. 400 - 405
(2022/01/04)
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- COMPOUNDS AS GLP-1R AGONISTS
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The present application provides compounds that may be used as a glucagon-like peptide-1 receptors (GLP-1R) agonist, or stereoisomers, tautomers, or pharmaceutically acceptable salts of any of the foregoing. Also provided are pharmaceutical compositions containing such compounds, or stereoisomers, tautomers, or pharmaceutically acceptable salts of any of the foregoing. Methods of prepare these compounds and compositions and method of using them to treat or present a disease or a condition mediated by GLP-1R.
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Paragraph 0712
(2022/03/07)
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- Synthesis method of thiocyclobutane-1,1-dioxide
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The invention discloses a thietane-1,1-dioxide synthesis method, and belongs to the technical field of battery electrolytic solutions. The method comprises: taking 1,3-epoxypropane and hydrogen sulfide as raw materials, adding Pt/Al2O3 and a molecular sieve, reacting for 3 to 4 h under the condition of 350 to 450 DEG C, putting the reaction product into a high-pressure reaction kettle, adding acetone, Pt/Al2O3 and a molecular sieve, introducing ozone under the protection of nitrogen, controlling the temperature of the high-pressure reaction kettle to be 40-80 DEG C and the pressure to be 0.1-0.8 MPa, and reacting for 1-5 hours to obtain thietane-1,1-dioxide. The synthesis method disclosed by the invention is simple, and the obtained thietane-1,1-dioxide is high in yield, high in purity andless in moisture.
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Paragraph 0015-0029
(2020/07/15)
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- A kinetic investigation, supported by theoretical calculations, of steric and ring strain effects on the oxidation of sulfides and sulfoxides by dimethyldioxirane in acetone
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The oxidations of alkyl 4-nitrophenyl, and dialkyl, sulfides and sulfoxides by dimethyldioxirane in acetone occur by concerted mechanisms but the sulfides respond differently from the sulfoxides to variation in the alkyl group. The reactions of the sulfides are inhibited by the steric effects of alkyl groups and these predominate over their inductive effects. By contrast, the reactions of these limited sets of sulfoxides are insensitive to alkyl steric effects but there is an indication of steric acceleration when a broader set of sulfoxides is considered. This behaviour is rationalised in terms of the differences in dipolar charge and its solvation between the ground state and transition state for the two types of substrate. The oxidations of cyclic sulfides and sulfoxides also exhibit contrasting behaviour. The reactivity of the sulfides is insensitive to ring strain but is explicable in frontier orbital terms whereas that of the sulfoxides is partly dependent upon the change in ring strain between reactant and product on oxidation, a difference rationalised in terms of the relative positions of the transition states in the reaction coordinates of the two oxidations. The reactivity of 4-, 5- and 6-membered cyclic sulfoxides is also dependent on a ring-size related property of the transition state. Calculations at the B3-LYP/6-31G* level of density functional theory on both ground states and transition states, including simulation of solvation by acetone, strongly support the mechanistic conclusions reached in this and earlier work.
- Hanson, Peter,Hendrickx, Ramon A. A. J.,Lindsay Smith, John R.
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scheme or table
p. 65 - 84
(2011/01/07)
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- Observed and calculated 1Hand 13C chemical shifts induced by the in situ oxidation ofmodel sulfides to sulfoxides and sulfones
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A series of model sulfides was oxidized in the NMR sample tube to sulfoxides and sulfones by the stepwise addition of meta-chloroperbenzoic acid in deuterochloroform. Various methods of quantum chemical calculations have been tested to reproduce the observed 1H and 13C chemical shifts of the starting sulfides and their oxidation products. It has been shown that the determination of the energy-minimized conformation is a very important condition for obtaining realistic data in the subsequent calculation of the NMR chemical shifts. The correlation between calculated and observed chemical shifts is very good for carbon atoms (even for the 'cheap' DFT B3LYP/6-31G* method) and somewhat less satisfactory for hydrogen atoms. The calculated chemical shifts induced by oxidation (the δd values) agree even better with the experimental values and can also be used to determine the oxidation state of the sulfur atom (-S-, -SO-, -SO2 -). Copyright
- Dracinsky, Martin,Pohl, Radek,Slavetinska, Lenka,Budesinsky, Milos
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experimental part
p. 718 - 726
(2011/05/15)
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- Synthesis of 2-alkyl(aryl)thietanes
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Thietane and its 2-substituted derivatives were synthesized. A general preparation procedure for the synthesis of thietanes bearing alkyl and aryl substituents in the α-position was developed. Using this procedure, 2-substituted thietanes can be obtained from cheap and easily accessible raw materials in three steps. 2-R-Thietanes (where R = H, CH3, C 4H9, C5H11, C6H 13, C6H5) and the corresponding sulfoxides and sulfones were synthesized and examined. Intermediate and by-products of the synthesis were studied. Nauka/Interperiodica 2007.
- Volynskii,Shevchenko
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p. 109 - 117
(2008/02/03)
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- SULFUR COMPOUNDS AS INHIBITORS OF HEPATITIS C VIRUS NS3 SERINE PROTEASE
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The present invention discloses novel compounds which have HCV protease inhibitory activity as well as methods for preparing such compounds. In another embodiment, the invention discloses pharmaceutical compositions comprising such compounds as well as methods of using them to treat disorders associated with the HCV protease.
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Page/Page column 344-345
(2010/02/14)
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- Reaction of singlet oxygen with thietane. A novel example of a self-catalyzed reaction which provides evidence for a thiadioxirane intermediate
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Singlet oxygen reacts with thietane, 1, to give the sulfoxide, 1SO, and a trace of sulfone, 1SO2. A mechanism which involves a novel substrate catalyzed interconversion of a persulfoxide and thiadioxirane intermediate is proposed. The data whic
- Clennan, Edward L.,Dobrowolski, Piotr,Greer, Alexander
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p. 9800 - 9803
(2007/10/03)
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- Reactions of 3-Chloro-2H-thiete 1,1-Dioxide
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3-Chloro-2H-thiete 1,1-dioxide, prepared by dichlorination of thietane 1,1-dioxide followed by dehydrochlorination, reacts with carbanions, amines, alcohols, and thiols to give 3-substituted thietane or 2H-thiete 1,1-dioxides.For example, reaction with the anion of dimethyl or diethyl malonate gives 3-thietane 1,1-dioxide. 3-Chloro-2H-thiete 1,1-dioxide also undergoes Diels-Ader reactions with butadiene and 1,3-diphenylisobenzofuran. 2,3-Dibromothietane 1,1-dioxide, 2,3-dibromo-3-chlorothietane 1,1-dioxide, 2-bromo-2H-thiete 1,1-dioxide, and 2-bromo-3-chloro-2H-thiete 1,1-dioxide also have been prepared.
- Sedergran, Thomas C.,Yokoyama, Masataka,Dittmer, Donald C.
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p. 2408 - 2412
(2007/10/02)
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- Oxygen-17 Nuclear Magnetic Resonance Spectroscopy of Sulfoxides and Sulfones. Alkyl Substituent Induced Chemical Shift Effects.
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Oxygen-17 NMR chemical shifts have been determined for a number of cyclic and acyclic as well as aliphatic, olefinic, and aryl sulfoxides and sulfones.The (17)O NMR chemical shifts for the acyclic, aliphatic, and aromatic sulfoxides reported here absorb in the narrow range between δ -20 and +20, while the cyclic, aliphatic sulfoxides absorb between δ -13 and +66 relative to external (but naturally abundant) H2(17)O.The sulfonyl oxygens are deshielded relative to sulfinyl oxygens, exhibiting chemical shifts for acyclic and cyclic sulfonyl oxygens between δ 120 and 183 for the sulfones reported here.Diastereotopic sulfonyl oxygens exhibit chemical shift nonequivalence.Substituent-induced chemical shift effects by a methyl or methylene group on the sulfinyl and sulfonyl oxygens are discussed.
- Dyer, John C.,Harris, David L.,Evans, Slayton A.
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p. 3660 - 3664
(2007/10/02)
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- Carbon-13 Chemical Shifts of 3-Substituted Thietanes, Thietane 1-Oxides and Thietane 1,1-Dioxides
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Carbon-13 chemical shifts of the α- and β-carbon atoms for 12 thietane 1,1-dioxides, 9 thietane 1-oxides and 7 thietanes with a variety of 3-substituents are correlated according to the nat
- Dittmer, Donald C.,Patwardhan, Bhalchandra H.,Bartholomew, John T.
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