2783. l-Cystine S,S-Dioxide

Nomenclature

CAS number: 30452-69-8
2-Amino-2-carboxyethyl 2-amino-2-carboxyethanethiosulfonate; l-cystine thiosulfonate; sacysyl-cysteine.
C6H12N2O6S2; mol wt 272.30.
C 26.47%, H 4.44%, N 10.29%, O 35.25%, S 23.55%.

Description and references

Oxidation product of cystine. Prepn: G. Toennies, T. F. Lavine, J. Biol. Chem. 113, 571 (1936); R. Emilozzi, L. Pichat, Bull. Soc. Chim. Fr. 1959, 1887. Orignally thought to be a mixture of two isomers, cystine S,S-dioxide and cystine S,S′-dioxide: G. E. Utzinger, Experientia 17, 374 (1961). Elucidaton of structures: G. Axelson et al., Spectrochim. Acta 23A, 2015 (1967); L. D. Setiawan et al., Surf. Interface Anal. 7, 188 (1985). Use in determn of sulfite: T. Ubuka et al., Anal. Biochem. 126, 273 (1982); idem et al., ibid. 140, 449 (1984).

Chemical structure

Properties

Solid, relatively unstable in aqueous solns; disproportionates to cystine and cysteine sulfinic acid.

Use

In detection of sulfites and thiosulfate.