1464-43-3Relevant articles and documents
Selenazolidine: A selenium containing proline surrogate in peptide science
Cordeau,Cantel,Gagne,Lebrun,Martinez,Subra,Enjalbal
, p. 8101 - 8108 (2016)
In the search for new peptide ligands containing selenium in their sequences, we investigated l-4-selenazolidine-carboxylic acid (selenazolidine, Sez) as a proline analog with the chalcogen atom in the γ-position of the ring. In contrast to proteinogenic selenocysteine (Sec) and selenomethionine (SeMet), the incorporation within a peptide sequence of such a non-natural amino acid has never been studied. There is thus a great interest in increasing the possibility of selenium insertion within peptides, especially for sequences that do not possess a sulfur containing amino acid (Cys or Met), by offering other selenated residues suitable for peptide synthesis protocols. Herein, we have evaluated selenazolidine in Boc/Bzl and Fmoc/tBu strategies through the synthesis of a model tripeptide, both in solution and on a solid support. Special attention was paid to the stability of the Sez residue in basic conditions. Thus, generic protocols have been optimized to synthesize Sez-containing peptides, through the use of an Fmoc-Xxx-Sez-OH dipeptide unit. As an example, a new analog of the vasopressin receptor-1A antagonist was prepared, in which Pro was replaced with Sez [3-(4-hydroxyphenyl)-propionyl-d-Tyr(Me)-Phe-Gln-Asn-Arg-Sez-Arg-NH2]. Both proline and such pseudo-proline containing peptides exhibited similar pharmacological properties and endopeptidase stabilities indicating that the presence of the selenium atom has minimal functional effects. Taking into account the straightforward handling of Sez as a dipeptide building block in a conventional Fmoc/tBu SPPS strategy, this result suggested a wide range of potential uses of the Sez amino acid in peptide chemistry, for instance as a viable proline surrogate as well as a selenium probe, complementary to Sec and SeMet, for NMR and mass spectrometry analytical purposes.
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Roy,J. et al.
, p. 2840 - 2842 (1970)
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Selenium and sulfur in exchange reactions: A comparative study
Steinmann, Daniel,Nauser, Thomas,Koppenol, Willem H.
, p. 6696 - 6699 (2010)
Cysteamine reduces selenocystamine to form hemiselenocystamine and then cystamine. The rate constants are k1 = 1.3 × 105 M-1 s-1; k-1 = 2.6 × 107 M-1 s-1; k2 = 11 M-1 s-1; and k-2 = 1.4 × 103 M-1 s-1, respectively. Rate constants for reactions of cysteine/selenocystine are similar. Reaction rates of selenium as a nucle'phile and as an electrophile are 2-3 and 4 orders of magnitude higher, respectively, than those of sulfur. Sulfides and selenides are comparable as leaving groups.
Diphosphoric acid compounds, and preparation method and application thereof
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Paragraph 0137; 0159, (2016/10/31)
The invention discloses compounds disclosed as Formula II. In the Formula II, R is disclosed in the specification, wherein R1 is H, OH or halogen; R2 is disclosed in the specification, n1=0-10, n2=0-10, and n3=0-10; Ar is aryl, arylidene, R99-substituted aryl or R99-substituted arylidene; at least one of R3, R4, R5 and R6 is selenium or sulfur atom, and the rest is carbon or nitrogen atom; and R3, R4, R5 and R6 are connected through a single bond or double bond. As for old patients with osteoporosis, the compounds can keep the osteocyte bone formation and bone destroy at an ideal dynamic balance.
