摘要
合成了六个新的廿员大环双核铜(Ⅱ)配合物作为Cu,Zn-SOD模拟物,其配体是用2,6-二甲酰基吡啶与1,3-丙二胺缩合而成,以SCN^-,Cl^-,Br^-,I^-,N_3^-,OH^-桥联。用多种物理方法进行表征,并用核黄素光照法研究与O_2^-反应的动力学,结果表明反应速率常数大约在10~7mol^(-1)·dm^3·s^(-1),其中以SCN^-为桥的配合物速率常数最高,而含N_3^-桥的最低。ESR谱研究结果表明前者与O_2^-为可逆的催化反应。后者为不可逆的氧化还原反应,这种情况与我们曾研究过的二乙酰基吡啶缩丙二胺合铜配合物一致。N_3^-桥对配合物的阻化作用与N_3^-对SOD的阻化作用类似。
Six new 20-membered macrocyclic bicopper (Ⅱ) complexes for modelling Cu, Zn-SOD were synthesized by condensation reactions of 2, 6-diformylpyridine with 1, 3-diaminopropane, in which two metal centers linked via OH^-, SCN^-, Br^-, I^-, Cl^- and N_3^-. They were characterized by several physical methods. Results of riboflavin illumination method showed that the rate constants of these model complexes reacting with O_2^- have values of ～10~7mol^(-1)·dm^3·s^(-1). Among them the complex with SCN^- bridging has the highest rate constant and that with N_3^- bridging has the lowest value. The reactions of complexes with O_2^- were studied by ESR. The results showed that the reversible catalysis mechanism takes place in the reaction of SCN^- bridged complex, and the reaction of N_3^-, bridged complex is irreversible oxidation-reduction mechanism. The results of the studies of ESR and kinetics are consistent with the complexes synthesized by condensation of diacetylpyridine with diaminopropane. Inhabitation of N_3^- to complex is similar to that of N_3^- to superoxide dismutase.
出处
《化学学报》
SCIE
CAS
CSCD
北大核心
1990年第12期1164-1170,共7页
Acta Chimica Sinica
基金
国家自然科学基金
