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Mercapto salts

Mercapto- or 4-alkylidenethia2oIium hydroxide inner salts (1) (X = S or CRR ) have not been described. [Pg.8]

Mercapto-imida2oliuin inner salts have been reported to rearrange under the influence of hydrochloric acid, producing S-aminothiazolium chlorides (Scheme 25) (36). Their N-acylated derivatives are obtained by cyclization of N-thiobenzoyl alkylaminoacetonitriles, effected with acyl or sulfonyl halides (Scheme 26) (34, 35). [Pg.13]

Salts are formed as with oxygen-containing compounds. For example, C2H5 — S—Na is named either sodium ethanethiolate or sodium ethyl sulfide. If mercapto- has been used as a prefix, the salt is named by use of the prefix sulfido- for —S . [Pg.38]

Hydrogen Sulfide andMercaptans. Hydrogen sulfide and propylene oxide react to produce l-mercapto-2-propanol and bis(2-hydroxypropyl) sulfide (69,70). Reaction of the epoxide with mercaptans yields 1-aLkylthio- or l-arylthio-2-propanol when basic catalysis is used (71). Acid catalysts produce a mixture of primary and secondary hydroxy products, but ia low yield (72). Suitable catalysts iaclude sodium hydroxide, sodium salts of the mercaptan, tetraaLkylammonium hydroxide, acidic 2eohtes, and sodium salts of an alkoxylated alcohol or mercaptan (26,69,70,73,74). [Pg.135]

When thiourea or thiosemicarbazide are used for substitution of a chlorine atom with a mercapto group, thiouronium salts are formed first, and they are hydrolysed by aqueous base. Other groups, such as alkoxy, alkyl, amino and cyano, if present, are usually not... [Pg.26]

Thiazolylium hydroxide, 5-mercapto-inner salt synthesis, 6, 305... [Pg.878]

Azauridine was also synthesized using the knowledge of the course of alkylation of 6-azauracil 2-methylmercapto derivatives (e.g., Section II,B,4,b). The 1-ribofuranosyl derivative obtained by reaction of the mercury salt of the 2-methylmercapto derivative with tri-O-benzoyl-jS-D-ribofuranosyl chloride on removal of the methyl-mercapto and then benzoyl groups yielded crystalline 6-azauridine, The main difference between uracil and 6-azauracil nucleosides consists in the preparation of cyclic nucleosides. It is known that uridine can be readily converted to cyclic nucleosides by the reaction of 2 (50-O-mesyl derivatives with nucleophilic agents, Analogous... [Pg.216]

N-(m-methylmercapto-phenyl)-aniline (MP 59° to 61°C) is prepared by condensing m-methyl-mercapto-aniline (BP 163° to 165°C/16 mm Hg) with the potassium salt of o-chloro-benzoic acid and decarboxylating the resultant N-(m-methylmercapto-phenyl)-anthranilic acid (MP 139° to 141°C) by heating, and then distilling. [Pg.1470]

N 24.12% brick red solid mp, decomps when heated over 300°. Insol in w and the usual organic solvents as well as weak acids and alkalies. Comm prepn (Ref 3) is from thiocyanic acid and/or thiocyanates either by anodic oxidation or by interaction with hydrogen peroxide or halogens. The yield is impure because it contains both H and O. The S content varies between 45 and 55%. Lab prepn of the pure polymer is by reacting the Na salt of 5-chlor-3-mercapto 1,2,4-thiodiazols with either acet, ethanol or w (Refs 1 2)... [Pg.829]

Yildirir and Okay (1991) recently described the mercapto-de-diazoniation of arene-diazonium salts by thioglycolic acid (HSCH2COOH) forming arylthioglycolic acids (Ar — SCH2COOH). [Pg.227]

Ferricyanide oxidation of 1,5-disubstituted thiocarbazones (116) give the mesoionic tetrazolium salts (117) under mild conditions (Eq. 21).190 This is in contrast to the strongly alkaline oxidation of carbazides leading to mercapto formazans as shown in Eq. 8 (Section 7.3.1.4). The heterocyclic triazine (118), obtained by the action of a diazonium salt on 2-... [Pg.235]

Thus, 5-amino-2-mercapto-l-methylimidazole (96 R = Me, R2 = SH) (65%) was obtained (48JCS2028) from 5-amino-2-methylaminothiazole (113 R1 = Me) on treatment with aqueous sodium carbonate. The aminoim-idazole (96 R1 = Me, R2 = SH) was found to be unstable in air, but gave a stable hydrochloride salt and on treatment with Raney nickel was desulfurized to give 5-amino-1-methylimidazole (96 R = Me, R2 = H) (58%), which was also unstable in air and was characterized as its picrate salt. [Pg.28]

The sulfide groups in mesoionic 1,3,4-thiadiazolium salts are activated toward nucleophilic substitution. The mercapto substituent of the thiadiazolium salt 117 can be displaced by cyclohexylamine to afford the 2//-thiadiazol-imine 118 (Equation 37) <2004BML4607>. [Pg.588]

Arene-l,2-dichalcogenolene ligands are generally stable as 1,2-dichalcogenols or 1,2-dichalcogenolato sodium salts.55,56 Aromatic 1,2-dithiolates can be prepared by following two different synthetic approaches, shown for bdt2- in Scheme 6, which start either from dihalo-substituted arenes or from mercapto-or vicinal dimercapto- arenes.57 62... [Pg.803]

A number of water-soluble calcium salts provide convenient vehicles for the administration of therapeutic anions. Probably the most widely encountered is the acetylsalicylate of soluble aspirin (patented 1935) the urea complex of calcium acetylsalicylate (water-solubility 231 gdm-3 at 310K, pH 4.8 (717)) is also widely used. Other examples include calcium bromide and bromolactobionate (sedatives), calcium 2-hydroxy-3-mercapto-l-propanesulfonateaurate(III) (chrysanol, antiarthritic), and calcium Af-carbamoylaspartate (tranquillizer). Calcium iron(II) citrate has been used to remedy iron deficiency - it has the advantage of being stable to air oxidation of the iron(II). The cyclamate anion is certainly not therapeutic, but is relevant here. [Pg.329]

Two approaches have been applied for the synthesis of imidazo[2,l + thia/,ole ring systems. Reaction of 2-mercapto-benzimidazole with perfluoro-2-methylpent-2-ene in the presence of triethylamine gave compound 419 (Equation 192), and cyclocondensation of 2-imidazolidinethione with the alkynyl(phenyl)iodonium salt 420 afforded product 421 (Equation 193) <2001RCB1446, 2003JCM715>. [Pg.181]

Glutamic acid and its salts (especially the sodium salt) enhance the flavour of many convenience foods. Bejaars et al. (1996) described the determination of free glutamic acid in soups, meat products and Chinese food. The method involves hot water extraction of test portions followed by filtration and dilution. The extracts were treated with N,N-dimethyl-2-mercapto-ethyl-ammonium chloride and o-phtaldialdehyde to convert glutamic acid into a stable fluorescent, l-alkylthio-2-alkyhsoindole. Homocysteic acid was used as the internal standard. Separation was made on a Ci8 column, eluted with... [Pg.117]


See other pages where Mercapto salts is mentioned: [Pg.413]    [Pg.8]    [Pg.11]    [Pg.115]    [Pg.300]    [Pg.126]    [Pg.160]    [Pg.161]    [Pg.557]    [Pg.619]    [Pg.865]    [Pg.155]    [Pg.231]    [Pg.255]    [Pg.229]    [Pg.170]    [Pg.265]    [Pg.265]    [Pg.80]    [Pg.217]    [Pg.222]    [Pg.2051]    [Pg.217]    [Pg.1225]    [Pg.53]    [Pg.83]    [Pg.497]    [Pg.412]    [Pg.413]   
See also in sourсe #XX -- [ Pg.3101 , Pg.3102 ]




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Mercapto

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