Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Thiosulfonate

In the 1995 edition of the Colourlndex the sulfur dyes are classified according to appHcation method and the stmcture of the intermediates, into ordinary or conventional dyes, leuco or prereduced dyes, and thiosulfonic derivatives of conventional dyes (solubilized sulfur dyes) (30). [Pg.170]

Ring contraction of 2-thiocephems has also been examined as a route to penems. Desulfurization of (82, n = 0) using triphenylphosphine gave mixtures of 5(R)- and 5(5)-penems (121). The stereochemical problem was neatiy overcome by regioselective oxidation to the thiosulfonate (82, n = 2) which underwent stereospecific thermal extmsion of sulfur dioxide (122) to give the S(R)-penem (83). [Pg.13]

Synthesis. The method of synthesis for Methylene Blue described in reference 14 is stiU the stepwise method of choice for thiazine dyes. /V,/V-Dimethy1-y-pheny1ene diamine [99-98-9], CgH22N2, reacts with sodium thiosulfate [7772-98-7] to form the thiosulfonic acid which condenses with /V, /V-dimetby1 ani1 ine [121 -69-7], CgH N, in the presence of sodium dichromate [10588-01-9] to the indamine, then with copper sulfate [18939-61 -2] and sodium dichromate to Methylene Blue (26). [Pg.423]

Three substituted 5-phenyl unsymmetrical disulfides have been prepared, i, ii, and iii —compounds i and ii by reaction of a thiol with a sulfenyl halide, compound iii from a thiol and an aiyl thiosulfonate (ArS02SAr). The disulfides are cleaved by reduction (NaBH4) or by treatment with excess thiol (HSCH2CH2OH). [Pg.303]

Thio-schwefelsaure, /. thiosulfuric acid, -sul-fatlosung, /. ihiosulfate solution. -sulfo-saure, /. thiosulfonic acid, -verbindung, /. thio compound, -zinnsaure, /. thiostannic acid. [Pg.445]

Benzopentathiepin rapidly reacts with sodium sulfinates RS02Na (R = alkyl or aryl) in ehloro-form/methanol at 20 °C to afford high yields of thiosulfonates RS02SNa.406... [Pg.493]

On the other hand, it seems to be generally agreed that combination of two sulfmyl radicals leads to thiosulfonate (RS02SR) as the final product22 the usual suggestion has been that it takes place via an initial head-to-tail combination of the radicals to give a O, S-sulfenyl sulfinate (5) which then rearranges to the thiosulfonate. [Pg.1084]

Scheme 2 summarizes the mechanism for the formation of thiosulfonate from sulfinyl radicals it is shown that the sulfinyl radicals combine to give both yic-disulfoxides and O, S-sulfenyl sulfinates, although they may rearrange to thiosulfonates either via a free radical route or via a concerted mechanism. The reader is referred to the recent review of Freeman22, who has collected and discussed the vast amount of information published on yic-disulfoxides and O, S-sulfenyl sulfinates. [Pg.1085]

Sulfinyl radicals have also been invoked in the synthetically useful reaction of alkane-and arenesulfmyl chlorides with activated zero-valent metals (Ag, Cu, Zn) to give the corresponding symmetrical thiosulfonates ... [Pg.1084]

Typically, the dithionite species disproportionates in aqueous media to afford the hydrogen sulfite and thiosulfonate nucleophiles.64 This finding suggests that sulfite esters (-0S02 ) and Bunte salts (-SS03-)65 could be formed upon iminium methide... [Pg.229]

Spiroazetidines have been ring-opened by sulfur nucleophiles to give sulfides, sulfates, or thiosulfonates (Scheme 1) <2003S288>. [Pg.1044]

Bloxham, D.P., and Cooper, C.K. (1982) Formation of a polymethylene bis(disulfide) inter-subunit crosslink between cys-281 residues in rabbit muscle glyceraldehyde-3-phosphate dehydrogenase using octamethylene bzs-(methane[35]thiosulfonate). Biochemistry 21, 1807. [Pg.1048]

Pascual, J.M., and Karlin, A. (1998) State-dependent accessibility and electrostatic potential in the channel of the acetylcholine receptor. Inferences from rates of reaction of thiosulfonates with substituted cysteines in the M2 segment of the alpha subunit./. Gen Physiol. 111(6), 717-739. [Pg.1102]

In soft cheeses, such as Brie, Camembert, and Limburger, the following sulfur compounds were implicated 3-(methylthio)propanol, MT, DMS, DMDS, DMTS, dimethyl tetrasulfide, methyl ethyl disulfide, diethyl disulfide, 2,4-dithiapentane, 3-methylthio-2,4-dithiapentane, methional, 2,4,5-trithiahex-ane, 1,1-fe-methylmercaptodisulfide, methyl thioacetate (=methanethiol acetate), benzothiazole, methylthiobenzothiazole, methyl ethyl sulfonate, methyl methane thiosulfonate, thiophene 2-aldehyde, and H2S.34 Many of these were only present in small amounts Limburger cheese was notable for 13.2% of DMDS, 0.5% of methyl thioacetate, and 0.8% of DMTS. [Pg.681]

Petrikovics I, Cannon EP, McGuinn 1995. Cyanide antagonism with carrier erythocytes and organic thiosulfonates. Fund Appl Toxicol 24 86-93. [Pg.264]

The reactions of thiosulfonates shown in general form in (167), and which constitute the majority of their chemistry, are, of course, substitution reactions at a dico-ordinate, or sulfenyl, sulfur. Substitutions of this type occur widely and with great frequency in the chemistry of all types of sulfenyl compounds. Because of their extreme importance in the chemistry of both thiolsulfonates and other sulfenyl derivatives, it is appropriate that we now review some of the major features regarding their mechanism that have emerged from the study of such reactions with various sulfenyl derivatives. [Pg.139]

As the AO with a direct nonspecific mechanism of action we have chosen Hypoxene - sodium poly(2,5-dihydroxiphenyl)-4-thiosulfonate. Besides a direct AO effect as a scavenger of free radicals it exerts an anti-hypoxic effect shunting I and II complexes of mitochondrial respiratory chain, which are inhibited as a consequence of hypoxia (Eropkin et al., 2007). Hypoxene was introduced into cell incubation media before illumination and left during cells further incubation. Hypoxene in the concentration of 40pg/ml, comparable to doses applied in vivo, completely blocked C60-induced phototoxicity (Table 7.3). Cellular viability has completely recovered to control level, which is a convincing evidence of free radical nature of cellular damage in photodynamic effect of fullerene. [Pg.149]

In wet acetonitrile, the oxidation of diaryldisuUrdes [119] and dialkyl disulfides (Aik 7 f-Bu) [120] affords the corresponding aryl and alkylthiosulfonates in good synthetic yields (Eq. 15). Thus, the oxidation of a cyclic disulfide, dibenzo(c,e)-1,2-dithiin (1,1) does not affect the S—S bond and results in a corresponding thiosulfonate, dibenzo(c,e)-l,2-dithiin-l,l-dioxide(Scheme 27) [121]. Such oxidized products can form in wet acetonitrile as well as in a dry solvent, but in the latter case this is probably a result of disproportionation of the primarily... [Pg.249]

The oxidation of sulfoxides by aliphatic peroxy acids is first order in both reactants the solvent effects have also been investigated. Thiosulfinates are oxidized by peroxy acids to thiosulfonates and not disulfoxides. It had previously been proposed that the disulfoxides are formed first but homolytically cleave and recombine to give thiosulfonates. A series of ab initio calculations were performed (at the 3-210 and 6-3IG levels) which indicate little difference in the rate of oxidation of S over S(0) in the gas phase but faster S(0) oxidation in a reaction cluster. ... [Pg.233]

Chemical/Physical. Oxidizes to the corresponding sulfoxide, sulfone, thiol, thiosulfone, and thiosulfoxide (Hartley and Kidd, 1987). Emits toxic fumes of chlorine, phosphorus, and sulfur oxides when heated to decomposition (Sax and Lewis, 1987). [Pg.1560]

Sulfenyl chlorides react with zincalkyl (or -aryl) sulfinates and also with sodium benzene sulfinate to yield the corresponding esters of thiosulfonic acid 13, 111, 161) ... [Pg.173]

Cymerman, J., u. J.B. Willis Die Ultrarotspektren und die chemische Struktur einiger Disulfide, Disulfone und Thiosulfonate. J. chem. Soc. 1951, 1332. [Pg.254]

Sulfur compounds with divalent sulfur functionalities are much more prone to dioxirane oxidation on account of their higher nucleophilicity compared to the above-presented oxygen-type nucleophiles. Examples of this type of dioxirane oxidation abound in the literature. Such a case is the oxidation of thiols, which may be quite complex and afford a complex mixture of oxidation products, e.g. sulfinic acids, sulfonic acids, disulfides, thiosulfonates and aldehydes , and is, therefore, hardly useful in synthesis. Nevertheless, the oxidation of some 9i/-purine-6-thiols in the presence of an amine nucleophile produces n >( -nucleoside analogs in useful yields (equation 19). This reaction also displays the general chemoselectivity trend that divalent sulfur functionalities are more reactive than trivalent sp -hybridized nitrogen compounds P. [Pg.1156]

Alkali acetylides react very easily with disulfides, R SSR, thiocyanates, R SC=N, and thiosulfonates, R SS02R The reactions can be carried out in liquid ammonia as well as in organic solvents and generally give excellent yields of the acetylenic sulfides, RChCSR [2,105]. Although sulfenyl halides seem suitable reagents for the introduction of alkylthio- or arylthio groups, they are seldom used for this reaction, because of their sensitivity and the... [Pg.129]


See other pages where Thiosulfonate is mentioned: [Pg.66]    [Pg.69]    [Pg.748]    [Pg.163]    [Pg.135]    [Pg.1512]    [Pg.449]    [Pg.176]    [Pg.1097]    [Pg.176]    [Pg.1097]    [Pg.256]    [Pg.1063]    [Pg.430]    [Pg.1017]    [Pg.66]    [Pg.249]    [Pg.378]    [Pg.199]    [Pg.8]    [Pg.1032]    [Pg.701]   
See also in sourсe #XX -- [ Pg.39 ]




SEARCH



Alanine thiosulfonate

Alanine thiosulfonate Volume

Bis-thiosulfonates

Disulfide thiosulfonates

Disulfides thiosulfonates

Ethyl thiosulfonate

Methane thiosulfonate

Propyl propane-thiosulfonate

Sulfate thiosulfonate

Thiosulfinates thiosulfonates

Thiosulfonate reductase

Thiosulfonate reductase Chlorella

Thiosulfonate synthesis

Thiosulfonates

Thiosulfonates

Thiosulfonates synthesis

Thiosulfonic

Thiosulfonic

Thiosulfonic Esters

Thiosulfonic acid, 5-

Thiosulfonic acids, esters

© 2024 chempedia.info