Dithiodiglycolic acid

ThioglycoHc acid can be identified by its in spectmm or by gas chromatography. Most of the by-products and self-esterification products are also detected by liquid chromatography, eg, thiodiglycolic acid, dithiodiglycolic acid, linear dimers, and polymers. Iron content can be assayed by the red sensitive complex of 1,10-phenanthroline [66-71-7] and ferrous ion of a mineralised sample. Ferric ion turns an aqueous ammonia solution deep red-violet. 

Phenylglyozel (15, 67) In 40 per cent yield by the action of alkali on diphenyl-dithiodiglycolic acid. Schoberl, Beminger, and Barren, Ber. 67, 1545 (1934). 

The resulting polymers always have the same functional group X at both chain ends. Therefore, telechelic polymers can be readily synthesized by the two-component iniferter system. An example is the polymerization of several monomers with 4,4J-azobiscyanovaleric acid (16) and dithiodiglycolic acid (17) as the initiator and the chain transfer agent, respectively, to synthesize the polymers having carboxyl groups at both chain ends [69]. 

The coupling reaction of dithiodiglycolic acid 398 and iV-hydroxysuccinimide 399, followed by the addition of methyl (4-aminomethyl)benzoate hydrochloride in the presence of Et3N, afforded an unexpected seven-membered 1,4,5-oxadithiepine 70 (Scheme 83) <2002TL4861>. 

Tang, F. and Hughes, J.A. (1999) Use of dithiodiglycolic acid as a tether for cationic lipids decreases the cytotoxicity and increases transgene expression of plasmid DNA in vitro. Bioconjug. Chem., 10, 791-796. 

Fig. 3.6. Partial (10%) neutralization of colloidal CaC03with dithiodiglycolic acid leading to comicellized calcium carbonate and calcium dithiodiglycolic carboxylate...

Disulfides are easily reducible to mercaptans a high yield of thioglycolic acid [222] from dithiodiglycolic acid was obtained by reduction of 2 A sulfuric acid at a lead cathode at —0.55 V (SCE). This reduction is one of the few examples of a controlled potential reduction prior to the invention of potentiostats. 

Trace quantities (less than lOpmol/g) of thioacetylated lysine and sorbed thioglycolic acid have also been reported in human hair treated by cold-waving reagents [1], Small quantities of mixed disulfide [5], sorbed dithiodiglycolic acid [57], and methionine sulfone [10] have also been found in hydrolyzates of hair treated by the thioglycolate cold-waving process. 

Athey, Mosher and Weston (19. 20) studied the use of S3ra net-rical difunctional chain transfer agents for synthesis of tele-chelic polymers. Dithiodiglycolic acid (DTDGA, II) was selected in the present work as a chain transfer agent to Increase the functionality of the PnBA. This particular chain transfer agent cleaves at the sulphur-sulphur bond in the presence of a free radical as shown below ... 

Disulphidoacetic Acid. Dithioglycollic acid, dithiodiglycollic acid, aym.-dicarboxydimethyl di-stUphidCt dimethyl diswphide dicarboxylic acid) HOOC-CH. S-8-CHo-COOH 04HeO Sa MW, 182... 

Figure 5.4 A tentative reaction mechanism for formation of carboxyl-terminated poly(2-ethyl hexyl acrylate) (CTPEHA) from free radical polymerisation of EHA in the presence of 4, 4 -azobis (4-cyanovaleric acid) (ABCVA) as a free radical initiator and dithiodiglycolic acid (DTDGA) as a chain transfer agent. (P = nM ) Reprinted with permission from D. Ratna, A.K. Banthia and P.C. Dtb, Journal of Applied Polymer Science, 2000, 78, 716. 2000, John Wiley and Sons Publishers...

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