碳酸酐酶的化学模拟——含三(取代吡唑)硼氢根的金属配合物[η~3-HB(3-Ar-5-Mepz)_3]MX(M=Ni,Cu,Zn,Cd;Ar=2'-thie,Ph;X=Cl,NO_3)的合成和表征  

The Chemical Modeling of Carbonic Anhydrase Synthesis and Characterization of Tris(pyrazoly)hydroborato Metal Complexes η 3 HB(3 Ar 5 Mepz) 3 MX (M=Ni, Cu, Zn, Cd; Ar=2 thie, Ph; X=Cl, NO 3)

作　　者：郭胜利[1,2] 刘省明[1,2] 殷元骐 郁开北[1,2] 

机构地区：[1]中国科学院兰州化学物理研究所 [2]中国科学院成都有机化学研究所

出　　处：《高等学校化学学报》1998年第5期741-747,共7页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金

摘　　要：合成了标题所示的一系列新的含三（取代吡唑）硼氢根的金属配合物，均通过元素分析、ＩＲ、１ＨＮＭＲ进行表征．配合物［η３－ＨＢ（３－（２－ｔｈｉｅ）－５－Ｍｅｐｚ）３］Ｚｎ（ＮＯ３）·１／２ＴＨＦ（２ｃ）的晶体结构测定表明，硝酸根是以不对称双齿方式与Ｚｎ原子配位（Ｚｎ—Ｏ（２）键长为０．１９６６（４）ｎｍ，Ｚｎ—Ｏ（３）键长为０．２４６３（４）ｎｍ）；而在镉的类似物｛［η３－ＨＢ（３－Ｐｈ－５－Ｍｅｐｚ）３］Ｃｄ（ＮＯ３）（ＴＨＦ）｝（２ｅ）中，ＮＯ－３则以双齿方式与Ｃｄ原子配位［Ｃｄ—Ｏ键长为０．２３３４（３）和０．２３５６（３）ｎｍ］．ＮＯ－３随金属不同取不同方式配位的现象，为解释锌、镉碳酸酐酶的不同活性（与酶活性中心配位的ＨＣＯ－３是ＮＯ－３的等电子体）提供了进一步的依据．配合物２ｃ和２ｅ均为三斜晶系，Ｐ１空间群，Ｚ＝２．２ｃ晶胞参数：ａ＝１．１６２５０（１０），ｂ＝１．２４２２（２），ｃ＝１．３２５９０（１０）ｎｍ；α＝７１．４１０（１０）°，β＝７３．０９０（１０）°，γ＝６５．６６０（１０）°；Ｒ＝０．０７５５．２ｅ晶胞参数：ａ＝１．１３０３０（１０），ｂ＝１．２０９９（２），ｃ＝１．２６０７（２?A series of tris(pyrazolyl)hydroborato metal complexes, η 3 HB(3 Ar 5 Mepz) 3 MX(M=Ni, Cu, Zn, Cd; Ar=2 thie, Ph; X=Cl, NO 3) had been synthesized and characterized. The determination of X ray crystal structure shows, the complex{ η 3 HB(3 (2 thie) 5 Mepz) 3 }Zn(NO 3)\51/2THF(2c) exhibits anisobidentate coordination of the nitrate ligand Zn O(2) 0.196 6(4) nm, Zn O(3) 0.246 3(4) nm , in contrast to the bidentate coordination fashion that is observed in the cadmium analogue{ η 3 HB(3 Ph 5 Mepz) 3 Cd(NO 3)(THF)}(2e) 0.233 4(3) and 0.235 6(3) nm . Cadmium substituted carbonic anhydrase(CA) is less active than zinc enzyme, among many other factors, such as the p K a of the coordinated water, that facile access to a unidentate bicarbonate intermediate may be an important requirement for CA activity. Both of 2c and 2e are triclinic with space group P 1, Z =2. For 2c, a =1.162 50(10) nm, b =1.242 2(2) nm, c =1.325 90(10) nm; α = 71.410(10)° , β =73.090(10)°, γ =65.660(10)°; final R =0.075 5. While for 2e they are: a =1.130 30(10) nm , b =1.209 9(2) nm, c =1.260 7(2) nm; α =102.050(10)° , β =91.780(10)° , γ =93.620(10)°; final R =0.030 2.

关 键 词：化学模拟 模拟物 碳酸酐酶 

分 类 号：Q55[生物学—生物化学]