title: Crystal structure of seleno-l-cystine di-hydro-chloride.
abstract: Numerous crystal structures are available for the dimeric amino acid cystine. In proteins it is formed by oxidation of the -SH thiol groups of two closely spaced cysteine residues, resulting in the formation of a familiar di-sulfide bridge. The title compound [systematic name: (R,R)-1,1'-dicarb-oxy-2,2'-(diselanedi-yl)diethanaminium dichloride], C6H14N2O4Se2 (2+)·2Cl(-), is the first example of a small mol-ecule structure of the biologically important analogue with a -CH2-Se-Se-CH2- bridging unit. Bond lengths and angles of seleno-l-cystine di-hydro-chloride and its isotypic sulfur analogue l-cystine di-hydro-chloride are compared.
authors.affiliation: Department of Chemistry, University of Oslo, PO Box 1033 Blindern, N-0315 Oslo, Norway.
authors.forename: Carl Henrik
authors.initials: CH
authors.lastname: Görbitz
authors.affiliation: Department of Chemistry, University of Oslo, PO Box 1033 Blindern, N-0315 Oslo, Norway.
authors.forename: Vladimir
authors.initials: V
authors.lastname: Levchenko
authors.affiliation: Department of Chemistry, University of Oslo, PO Box 1033 Blindern, N-0315 Oslo, Norway.
authors.forename: Jevgenijs
authors.initials: J
authors.lastname: Semjonovs
authors.affiliation: Department of Chemistry, University of Oslo, PO Box 1033 Blindern, N-0315 Oslo, Norway.
authors.forename: Mohamed Yusuf
authors.initials: MY
authors.lastname: Sharif
keywords: Se—Se bridge; cancer therapy; crystal structure; isotypism; l-cystine analogue