Model Complexes for Non-Redox Active Metalloenzymes(Structural and Functional Model Complexes for Non-Redox Active Metalloenzymes Involving Dinuclear Metal Centers)

1.含有Mg^2+、Ca^2+、Mn^2+和Zn^2+等非氧化还原活性离子的羧基桥联双核金属中心是存在于磷酸酯加工金属酶活性中心的重要生物无机基序。我们系统地研究了非氧化还原活性的双金属配合物，利用双羧酸配体，间苯二甲胺双（Kemps三酸酰亚胺）（H^2XDK）。通过<12>[ZnM（XDK）（acac）_2（CH_3OH）_2]与（PhO）_2PO_2H_2的反应，合成了含锌的磷酸二苯酯同、异二金属配合物[ZnM（XDK）{μ-η ^ -（PhO）_2O_2}{η ^-（PhO_2PO_2}（CH_3OH）_2（H_2O）]（M = Zn，Co）。类似的Mg_2、Mn_2和Ca_2络合物。[M_2（XDK）{mueta_2-（PhO）_2PO_2）{mu_1-（PhO）_2PO_2}（CH_3OH）m（H_2O）n]（M = Mg，m = 3，n = 1 ; M = Mn，m = n = 2 ; M = Ca，m = 3，n = 1）。通过X射线晶体学表征了配合物的结构，表明配合物由XDK和（PhO）_2PO_2桥联的不对称双金属中心组成。变温^<3l>p{^1H} ...更多信息 NMR实验表明，末端配位的磷酸酯配体在溶液中从双金属中心解离并与桥接中心交换。磷酸酯交换速率的增加顺序为Ca^2+&gt; Zn^2+&gt; Mg^2+，这为理解磷酸酯加工金属酶提供了有用的信息。合成了Co（II）、Cu（I）和Cu（II）的双核配合物，并研究了它们的生物相关反应.碳水化合物与金属离子的相互作用在生物系统中至关重要。我们研究了各种过渡金属与糖配体配合物的合成、表征和反应性。单核Co（II）配合物[Co（II）（（L-Rha或D-Man）_3-tren）]^&lt;2+&gt;通过金属中心的手性反转对SO^ anton具有分子识别性能<2->。合成了过氧桥联双核钴（III）配合物[（（D-Glc，or Mal）_2-tren）Co（mu-02）Co（（D-Glc，or Mal）_2-tren）] X_3（X = Cl，Br），并通过X射线衍射对其结构进行了表征。双核结构进一步由糖部分之间的一些氢键支持。有趣的是，几乎可逆的二氧结合通过μ-过氧二聚体监测电子吸收光谱的变化后，紫外线照射;新的锰（II）锰（III）锰（II）三核配合物与甘露吡喃糖桥的uri的制备和表征的X-射线晶体学。因此，许多尝试是为了形成具有tacn锚定的糖部分的仿生双金属中心。少

1. Carboxylate-bridged dinuclear metal centers containing non-redox active ions such as Mg^<2+>, Ca^<2+>, Mn^<2+> and Zn^<2+> arc an important bioinorganic motif occurring at the active centers of phosphate ester-processing metalloenzymes. We have systematically studied non-redox active dimetallic complexes by utilizing a biscarboxylate ligand, m-xylylendiamine bis(Kemps triacid imide) (H^2XDK). Zinc-containing homo- and heterodimetallic complexes with diphenylphosphate, [ZnM(XDK){ mu-eta^<12>-(PhO)_2O_2}{eta^1-(PhO_2PO_2}(CH_3OH)_2(H20)]( M = Zn, Co), were prepared in the reactions of [ZnM(XDK)(acac)_2(CH_3OH)_2]with (PhO)_2PO_2H_2. Analogous Mg_2, Mn_2, and Ca_2 complexes. [M_2(XDK){mueta_2-(PhO)_2PO_2){mu_1-(PhO)_2PO_2}(CH_3OH)m(H_2O)n] ( M = Mg, m = 3, n = 1 ; M = Mn, m = n = 2 ; M = Ca, m = 3, n = 1), were obtained. Complexes were characterized by X-ray crystallography, consisting of an asymmetric dimetallic center bridged by XDK and (PhO)_2P0_2, . Variable-temperature ^<3l>p{^1H} … More NMR experiments demonstrated that the terminally coordinated phosphate ester ligand dissociates from the dimetallic center in solution and exchanges with the bridging one. The phosphate ester exchange rate increases in the order Ca^<2+> > Zn^<2+> > Mg^<2+>, providing useful information for understanding phosphate ester-processing metalloenzymes. New dinuclear complexes of Co(II), Cu(I), and Cu(II) were also prepared and their biorelevant reactions were examined.2. Interactions of carbohydrates with metal ions are vital in biological systems. We have studied the synthesis, characterization, and reactivities of various transition metal complexes with sugar ligands. The mononuclear Co(II) complexes with a heptadentate N-glycoside ligand, [Co(II)((L-Rha or D-Man)_3-tren)]^<2+> showed a molecular recognition property for SO^<2-> anton through chiral inversion of the metal center. Peroxo-bridged dinuclear cobalt (III) comp1ex, [((D-Glc, or Mal)_2-tren)Co(mu-02)Co((D-Glc, or Mal)_2-tren)]X3 (X = Cl, Br), were prepared and characterized by X-ray crystallography to consist of two octahedral Co(III) ions bridged by peroxide. The dinuclear structure is further supported by some hydrogen bonds between the sugar moieties. Interestingly, almost reversible dioxygen binding through the mu-peroxo dimer was monitored by electronic absorption spectral changes upon UV irradiation ; Novel Mn(II)Mn(III)Mn(II) trinuclear complexes with mannopyranose-bridging uri'rs were prepared and characterized by X-ray crystallography. Futhermore, many attempts were made to form biomimetic dimetal centers with tacn-anchored sugar moieties. Less