New Copper(II)/Cyclic Tetrapeptide System That Easily Oxidizes to Copper(III) under Atmospheric Oxygen
详细信息 查看全文
- 作者：Alessandro Pratesi ; Piero Zanello ; Gianluca Giorgi ; Luigi Messori ; Franco Laschi ; Angela Casini ; Maddalena Corsini ; Chiara Gabbiani ; Marco Orfei ; Claudia Rosani ; Mauro Ginanneschi
- 刊名：Inorganic Chemistry
- 出版年：2007
- 出版时间：November 26, 2007
- 年：2007
- 卷：46
- 期：24
- 页码：10038 - 10040
- 全文大小：66K
- 年卷期：v.46,no.24(November 26, 2007)
- ISSN：1520-510X
文摘
A 13-membered ring cyclic tetrapeptide was synthesized by thesolid-phase peptide synthesis method, and its copper(II) coordination properties were analyzed by optical spectroscopy, massspectrometry, and electrochemistry. All collected data stronglysupport the presence, at alkaline pH, of a stable peptide/copper(III) complex that is formed in solution by atmospheric dioxygenoxidation. On the basis of previous studies on cyclic peptide/coppersystems, we suggest that the copper(III) ion is at the center ofthe ligand's cavity being coordinated to four deprotonated amidenitrogen atoms. This donor set would greatly lower the redoxpotential for the CuIII/CuII couple, thus allowing easy oxidation ofthe coordinated copper(II) by atmospheric oxygen.