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辅酶B_(12)是多种分子内重排酶和核苷还原酶的辅因子,它的Co—C键在酶催化过程中会断裂产生自由基,引发底物的重排,在催化反应过程中起重要作用,包含Co—C键的辅酶B_(12)模型化合物与环糊精作用形成超分子的研究尚未见报道,由于该超分子比单纯的辅酶β_(12)模型物增加了疏水腔,使模型更接近真实体系,因而研究它们的性质,尤其是Co—C键在包结前后的变化,对于阐明与辅酶B_(12)有关的酶催化反应机理有重要意义,我们以RCo(DMG)_2L(R=i-C_4H_9,n-C_4H_9,n-C_5H_(11),c-C_6H_(11),PhCH_2.DMG=丁二酮肟.L=H_2O,NH_3)为辅酶B_(12)模型与β-环糊精作用,首次合成了一系列B_(12)模型超分子配合物,并用元素分析、FAB-MS、~1H NMR进行了表征,部分化合物进行了X射线衍射结构分析。 1 实验部分 β-CD(南京食品发酵所)经水重结晶两次,于真空80℃干燥至恒重后使用,元素分析使用240C元素分析仪,~1H NMR在Bruker AM-500MHz核磁共振仪上测定,FAB-MS在GCMS质谱仪上测试。晶体结构分析在美国Emory大学的低温(-100℃)四圆衍射仪上进行。 RCo(DMG)_2H_2O参照文献合成,RCo(DMG)_2H_2O/β-CD的合成以i-C_4H_9Co·
Coenzyme B_ (12) is a cofactor of a variety of intramolecular and nucleoside reductase enzymes. Its Co-C bond cleaves during the enzymatic catalysis to generate free radicals and initiates the rearrangement of the substrate. During the catalytic reaction (12) model compounds with Co-C bond and cyclodextrin to form supramolecules have not been reported yet. Because the supramolecular structure is more hydrophobic than the simple coenzyme β 12 model body , So that the model closer to the real system, and thus study their properties, especially the Co-C bond in the package before and after changes in the coenzyme B_ (12) to clarify the enzymatic reaction mechanism is important, we RCo (DMG ) _2L is a model of coenzyme B_ (12) and the model of coenzyme B_ (12) is the same as that of coenzyme B_ (12) β-cyclodextrin, a series of supramolecular complexes of B 12 were synthesized and characterized by elemental analysis, FAB-MS and 1H NMR. Some of the compounds were characterized by X-ray diffraction. 1 Experimental Part β-CD (Nanjing Food Fermentation) was recrystallized twice from water and dried at 80 ° C under vacuum until constant weight was used. The elemental analysis was carried out on a Bruker AM-500MHz nuclear magnetic resonance spectrometer using ~ 1H NMR FAB-MS was tested on a GCMS mass spectrometer. Crystal structure analysis was performed on a low temperature (-100 ° C) four-circle diffractometer at Emory University, USA. RCo (DMG) _2H_2O Reference Materials Synthesis, Synthesis of RCo (DMG) _2H_2O / β-CD Starting with i-C_4H_9Co ·