Oxidant dependent oxidation of copper bound catecholate: Catecholase versus catechol dioxygenase activity

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• 作者：Dó ; ra Lakk-Bogá ; th^a ; Ró ; bert Csonka^a ; Noé ; mi Lorencz^a ; Michel Giorgi^b ; Gá ; bor Speier^a ; Jó ; zsef Kaizer^a ; ^{kaizer@almos.vein.hu" class="auth_mail" title="E-mail the corresponding author}
• 关键词：Copper complex ; Catecholase ; Catechol dioxygenase ; Enzyme mimics ; Intradiol cleavage
• 刊名：Polyhedron
• 出版年：2015
• 出版时间：14 December 2015
• 年：2015
• 卷：102
• 期：Complete
• 页码：185-192
• 全文大小：1558 K

文摘

A series of new mixed ligand copper complexes Cu^II(PBI)(O₂Ncat) (1) (PBI = 2-(2-pyridyl)-benzimidazole), Cu^II(DMPBI)(O₂Ncat) (2) (DMPBI = 5,6-dimethyl-2-(2-pyridyl)-benzimidazole), Cu^II(PBO)(O₂Ncat) (3) (PBO = 2-(2-pyridyl)-benzoxazole), Cu^II(PBT)(O₂Ncat) (4) (PBT = 2-(2-pyridyl)-benzothiazole), and Cu(TBA)(O₂Ncat) (5) (TBA = 4-(1H-1,3-benzodiazol-2-yl)-1,3-thiazole) have been synthesized by classic organic, bioinorganic methods. The complexes have been found to mimic catechol oxidase and catechol dioxygenase activity depending on the oxidant used. Triplet state dioxygen activates the complex leading to intradiol cleavage product, 2-nitromuconic acid while sterically more demanding tert-butyl hydroperoxide (TBHP) oxidizes the 4-nitrocatechol (4-O₂NcatH₂) ligand into 4-nitrobenzoquinone. We have also found that the electron density on the copper center significantly increase the reactivity toward the oxidant used.