- Conversion of thiols into sulfonyl halogenides under aerobic and metal-free conditions
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An environmentally benign, metal-free synthesis of sulfonyl chlorides and bromides from thiols in the presence of ammonium nitrate, an aqueous solution of HCl and HBr and oxygen as a terminal oxidant was developed. The reactivity of various substituted thiophenols, benzylic-, aliphatic- and heteroaromatic thiols was examined. Ammonium nitrate served as a source of nitrogen oxides (NO/NO2), which are the crucial players in a redox-catalytic cycle. Sulfonyl chlorides and bromides were isolated without extraction and "filtered" over a short pad of silica gel; the use of solvents was greatly reduced in comparison with traditional isolation and purification. A "one-pot" protocol for the conversion of thiol into sulfonamide is also demonstrated. Scale-up experiments on the preparation of sulfonyl chloride and bromide are shown. A possible reaction pathway is discussed.
- Jereb, Marjan,Hribernik, Luka
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supporting information
p. 2286 - 2295
(2017/07/24)
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- Substituted Disulfonamide Compounds
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Substituted disulfonamide compounds corresponding to formula I: In which R1, R2, R3, R4a, R4b, R5a, R5b, R8, R9a, R9b, R10, R11, a, b, s, t and A have defined meanings, pharmaceutical compositions containing one or more such compounds, processes for preparing such compounds, and a method of using such compounds for the treatment or inhibition of pain and/or other conditions mediated by the bradykinin receptor 1 (BR1).
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Page/Page column 43
(2010/06/22)
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- Phenylenediamine urotensin-II receptor antagonists and CCR-9 antagonists
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The present invention relates to urotensin II receptor antagonists, CCR-9 antagonists, pharmaceutical compositions containing them and their use.
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- DISSOCIATION OF SUBSTITUTED BENZENESULPHONAMIDES IN WATER, METHANOL AND ETHANOL
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Thirteen monosubstituted arylsulphonamides (XC6H4SO2NH2) and two 3,4-disubstituted arylsulphonamides (X2C6H3SO2NH2) have been synthetized and their dissociation constants have been measured by potentiometric titration in water, methanol, and ethanol.The Hammett substitution dependences have been calculated for all the media, and changes in the reaction constants due to transition from water to alcohols are discussed in confrontation with analogous dependences of benzoic acids.The reaction constant ρ found in methanol is lower than that in water.The dissociation constants have been treated by the method of the principal components and by multiple linear regression.
- Ludwig, Miroslav,Pytela, Oldrich,Kalfus, Karel,Vecera, Miroslav
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p. 1182 - 1192
(2007/10/02)
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