Title of article :
Functional model for intradiol-cleaving catechol 1,2-dioxygenase: Synthesis, structure, spectra, and catalytic activity of iron(III) complexes with substituted salicylaldimine ligands
Author/Authors :
Chi-Hueng Wang، نويسنده , , Jianwei Lu، نويسنده , , Ho-Hsiang Wei، نويسنده , , Masuo Takeda، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2007
Pages :
9
From page :
2944
To page :
2952
Abstract :
A series of mononuclear iron(III) complexes with containing phenolate donor of substituted-salicylaldimine based ligands [Fe(L1)(TCC)] · CH3OH (1), [Fe(L2)(TCC)] · CH3OH (2), [Fe(L3)(TCC)] (3), and [Fe(L4)(TCC)] (4) have been prepared and studied as functional models for catechol dioxygenases (H2TCC = tetrachlorocatechol, or HL1 = N′-(salicylaldimine)-N,N-diethyldiethylenetriamine, HL2 = N′-(5-Br-salicylaldimine)-N,N-diethyldiethylenetriamine, HL3 = N′-(4,6-dimethoxy-salycyl-aldimine)-N,N-diethyl-diethylenetriamine, HL4 = N′-(4-methoxy-salicylaldimine)-N,N-diethyl-diethylenetriamine). They are structural models for inhibitors of enzyme-substrate adducts from the reactions of catechol 1,2-dioxygenases. Complexes 1–4 were characterized by spectroscopic methods and X-ray crystal structural analysis. The coordination sphere of Fe(III) atom of 1–4 is distorted octahedral with N3O3 donor set from the ligand and the substrate TCC occupying cis position, and Fe(III) is in high-spin (S = 5/2) electronic ground state. The in situ prepared iron(III) complexes without TCC, [Fe(L1)Cl2], [Fe(L2)Cl2], [Fe(L3)Cl2], and [Fe(L4)Cl2] are reactive towards intradiol cleavage of the 3,5-di-tert-butylcatechol (H2DBC) in the presence of O2 or air. The reaction rate of catechol 1,2-dioxygenase depends on the redox potential and acidity of iron(III) ions in complexes as well as the substituent effect of the ligands. We have identified the reaction products and proposed the mechanism of the reactions of these iron(III) complexes with H2DBC with O2.
Keywords :
M?ssbauer effect , crystal structure , Model of catechol 1 , 2-dioxygenase , 2-dioxygenase , Model of catechol 1 , Mononuclear iron(III) complexes , Salicylaldimine , Non-heme iron protein
Journal title :
INORGANICA CHIMICA ACTA
Serial Year :
2007
Journal title :
INORGANICA CHIMICA ACTA
Record number :
1324682
Link To Document :
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