598-41-4Relevant articles and documents
Nickel(III) oxidation of its glycylglycylhistamine complex
Green, Brandon J.,Tesfai, Teweldemedhin M.,Margerum, Dale W.
, p. 3508 - 3514 (2004)
The doubly-deprotonated Ni(III) complex of Gly2Ha (where Ha is histamine) undergoes base-assisted oxidative self-decomposition of the peptide. At ≤ p[H+] 7.0, a major pathway is a two-electron oxidation at the a-carbon of the N-terminal glycyl residue. Major products (up to 73%) of this two-electron oxidation are glyoxylglycylhistamine and ammonia. Glyoxylglycylhistamine will decay to give isocyanatoacetylhistamine and formaldehyde. Two-electron oxidations of the second glycyl and histamine residues occur as minor pathways (12% of the total possible reaction). Above p[H+] 8.5, two Ni(III)-peptide complexes form an oxo bridge in the axial positions to give a reactive dimer species. This proximity allows the resulting Ni(III)-peptide radical intermediates to undergo peptide-peptide cross-linking at the N-terminal glycyl residues. The products found below p[H+] 7.0 are observed above p[H+] 8.5 as well, although in lower yields. In contrast to this work, NiIII(H- 2Gly2HisGly) undergoes a four-electron oxidation at the N-terminal glycyl residue. Oxidation at the internal glycyl and histidyl residues are not observed. The reactivity of NiIII(H -2Gly2Ha)+ is also different than Cu III(H-2Gly2Ha)+, which undergoes a two-electron oxidation at the histamine group with no peptide-peptide cross-linking in basic solution.
Preparation method of 2, 6-dichloropyrazine
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Paragraph 0034-0035, (2020/04/22)
The invention discloses a preparation method of 2, 6-dichloropyrazine. The method comprises the following steps: taking glycine and glyoxal as raw materials, carrying out ammoniation and cyclization reactions to prepare 2-hydroxypyrazine sodium; and reacting 2-hydroxypyrazine sodium with thionyl chloride under the catalytic action of N,N-diisopropylethylamine to prepare 2-chloropyrazine; wherein pyridine is used as a solvent, and 2-chloropyrazine is subjected to chlorination of chlorine to obtain 2,6-dichloropyrazine. The method has the advantages that the raw material namely glycine is cheapand easily available, and phosphorus oxychloride is not used as a chlorination reagent, so that the generation of organic phosphorus-containing wastewater is greatly reduced, and an effective way is provided for efficient green industrial production of 2, 6-dichloropyrazine.
HEMIAMINAL-TAG FOR PROTEIN LABELING AND PURIFICATION
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Page/Page column 22, (2018/06/30)
The invention pertains to the synthesis, isolation, and characterization of hemiaminal for selective labeling of peptides, proteins, antibodies, and organic fragments with -C(=0) CH2NH2 and derivatives with -CH2NH2 group over -C(=0) CHRNH2 group (where R≠H). The invention also pertains to the method of single-site immobilization of proteins through N-terminus Gly on solid phase. The invention includes late-stage tagging of N-terminus Gly with an affinity tag, 19F NMR probe, and a fluorophore and a method for metal-free protein purification and isolation of analytically pure proteins.
Tuning the reactivity of nitriles using Cu(ii) catalysis-potentially prebiotic activation of nucleotides
Liu, Ziwei,Mariani, Angelica,Wu, Longfei,Ritson, Dougal,Folli, Andrea,Murphy, Damien,Sutherland, John
, p. 7053 - 7057 (2018/09/25)
During the transition from prebiotic chemistry to biology, a period of solution-phase, non-enzymatic activation of (oligo)nucleotides must have occurred, and accordingly, a mechanism for phosphate activation must have existed. Herein, we detail results of an investigation into prebiotic phosphate activation chemistry using simple, prebiotically available nitriles whose reactivity is increased by Cu2+ ions. Furthermore, although Cu2+ ions are known to catalyse the hydrolysis of phosphodiester bonds, we found this deleterious activity to be almost completely suppressed by inclusion of amino acids or dipeptides, which may suggest a productive relationship between protein and RNA from the outset.
