Synthesis, structure and catecholase activity study of dinuclear copper(II) complexes †
作者:Jörg Reim、Bernt Krebs
DOI:10.1039/a704245k
日期:——
A series of dinuclear copper(II) complexes as models for the type 3 copper protein catechol oxidase were synthesised. They were characterised by spectroscopic, electrochemical, and in some cases, by single-crystal X-ray diffraction studies: [Cu2(L1)(OH)(EtOH)(H2O)][ClO4]2·H2O 1, [Cu2(L2)(OH)][NO3]22, [Cu2(L3)(OMe)(MeOH)(ClO4)]ClO43, [Cu2(L4)(OH)(MeOH)2][BF4]24, [Cu2(L5)(OMe)][ClO4]2·2MeOH 5, [Cu2(L6)(OMe)(MeOH)(ClO4)]ClO46 and [Cu2(L7)(OMe)(MeOH)(ClO4)]ClO47 (HL1 = 4-bromo-2,6-bis(4-methylpiperazin-1-ylmethyl)phenol, HL2 = 4-bromo-2,6-bis[(2-pyridylmethyl)aminomethyl]phenol, HL3 = 4-bromo-2,6-bis[2-(2-pyridyl)ethyl]aminomethyl}phenol, HL4 = 4-bromo-2,6-bis[2-(1-methyl-2-imidazolyl)ethyl]aminomethyl}phenol, HL5 = 4-bromo-2-(4-methylpiperazin-1-ylmethyl)-6-[(2-pyridylmethyl)aminomethyl]phenol, HL6 = 4-bromo-2-(4-methylpiperazin-1-ylmethyl)-6-[2-(2-pyridyl)ethyl]aminomethyl}phenol and HL7 = 4-bromo-2-(4-methylpiperazin-1-ylmethyl)-6-[2-(1-methyl-2-imidazolyl)ethyl]aminomethyl}phenol). The copper centres are µ-phenoxo bridged by the pentadentate dinucleating ligand and exogenously µ-hydroxo or µ-methanolato bridged. Complex 1 crystallises in P21/c with a = 16.913(3), b = 11.046(2), c = 16.617(3) Ã
, β = 94.06(3)°, U = 3097 Ã
3 and Z = 4. Complex 3 crystallises in P21/n with a = 10.592(2), b = 12.123(2), c = 24.482(5) Ã
, β = 92.97(3)°, U = 3139 Ã
3 and Z = 4. Complex 4 crystallises in Pbcn with a = 16.043(3), b = 12.689(3), c = 15.810(3) Ã
, UÂ =Â 3218 Ã
3 and Z = 4. Complex 6 crystallises in P21/c with a = 17.889(4), b = 10.401(2), c = 16.269(4) Ã
, β = 92.94(2)°, U = 3023 Ã
3 and Z = 4. Complex 7 crystallises in P21/c with a = 17.349(3), b = 8.828(2), c = 19.797(4) Ã
, β = 94.04(3)°, U = 3025 Ã
3 and ZÂ =Â 4. A catecholase activity study revealed that only complexes 1, 5, 6 and 7 have significant catalytic activity with respect to the aerial oxidation of 3,5-di-tert-butylcatechol. A kinetic treatment on the basis of the MichaelisâMenten model was applied.
合成了一系列双核铜 (II) 配合物作为 3 型铜蛋白儿茶酚氧化酶的模型。它们通过光谱、电化学以及在某些情况下通过单晶 X 射线衍射研究进行了表征:[Cu2(L1)(OH)(EtOH)(H2O)][ClO4]2·H2O 1,[Cu2(L2) )(OH)][NO3]22, [Cu2(L3)(OMe)(MeOH)(ClO4)]ClO43, [Cu2(L4)(OH)(MeOH)2][BF4]24, [Cu2(L5) (OMe)][ClO4]2·2MeOH 5、[Cu2(L6)(OMe)(MeOH)(ClO4)]ClO46 和 [Cu2(L7)(OMe)(MeOH)(ClO4)]ClO47 (HL1=4 -溴-2,6-双(4-甲基哌嗪-1-基甲基)苯酚,HL2=4-溴-2,6-双[(2-吡啶甲基)氨基甲基]苯酚,HL3=4-溴-2, 6-双[2-(2-吡啶基)乙基]氨基甲基}苯酚,HL4=4-溴-2,6-双[2-(1-甲基-2-咪唑基)乙基]氨基甲基}苯酚,HL5 =4-溴-2-(4-甲基哌嗪-1-基甲基)-6-[(2-吡啶甲基)氨基甲基]苯酚,HL6=4-溴-2-(4-甲基哌嗪-1-基甲基)-6 -[2-(2-吡啶基)乙基]氨基甲基}苯酚和 HL7=4-溴-2-(4-甲基哌嗪-1-基甲基)-6-[2-(1-甲基-2-咪唑基)乙基]氨基甲基}苯酚)。铜中心由五齿二核配体和外源性μ-羟基或μ-甲醇桥联成μ-苯氧基桥接。配合物 1 在 P21/c 中结晶,其中 a = 16.913(3)、b = 11.046(2)、c = 16.617(3) ×、β = 94.06(3)°、U = 3097 ×3 和Z = 4. 配合物 3 在 P21/n 中结晶,a = 10.592(2), b = 12.123(2), c = 24.482(5) ×, β = 92.97(3)°, U = 3139 × 3 和 Z = 4。配合物 4 在 Pbcn 中结晶,a = 16.043(3),b = 12.689(3),c = 15.810(3) ×,U = 3218 × 3 和 Z = 4. 配合物 6 在 P21/c 中结晶,a=17.889(4), b=10.401(2), c=16.269(4) ×, β=92.94(2)°, U=3023 3 和 Z = 4。配合物 7 在 P21/c 中结晶,a = 17.349(3), b = 8.828(2), c = 19.797(4) , β = 94.04(3)° ,U=3025×3,Z=4。儿茶酚酶活性研究表明,只有配合物1、5、6和7对3,5-二叔丁基儿茶酚的空气氧化具有显着的催化活性。应用基于 Michaelis-Menten 模型的动力学处理。