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Two multidentate ligands 2,9-di[6’-(2″-hydroxyl-3″-methoxyphenyl)-n-2’,5’-diazahexyl]-1,10-phenanthroline(LA)and 2,9-di(6’-α-phenol-n-2’,5’-diazahexyl)-1,10-phenanthroline(LB)were synthesized and fully characterized.Protonation of the ligands and the stability of the complexes of the ligands with divalent metal ions were investigated.The trinuclear metal complexes [Cu(Ⅱ)and Zn(Ⅱ)] of the ligands were studied,as catalysts,for the transphosphorylation of the RNA-model substrate 2-hydroxypropyl-p-nitrophenyl phosphate(HPNP).The second-order rate constants of HPNP-hydrolysis catalyzed by M3L and M3LH-1 were obtained,which indicated that Zn3LBH-1 was the most efficient catalyst among them.The proposed mechanisms included the activation of the substrate via binding to the metal ions and intramolecular nucleophilic attack by the deprotonated C2-hydroxyl of HPNP.
Two multidentate ligands 2,9-di [6 ’- (2 “-hydroxyl-3” -methoxyphenyl) -n-2’, 5’-diazahexyl] -1,10-phenanthroline (LA) 6’-α-phenol-n-2 ’, 5’-diazahexyl) -1,10-phenanthroline (LB) were synthesized and fully characterized. Protonation of the ligands and the stability of the complexes of the ligands with divalent metal ions were investigated the trinuclear metal complexes [Cu (II) and Zn (II)] of the ligands were studied, as catalysts for the transphosphorylation of the RNA-model substrate 2-hydroxypropyl-p- nitrophenyl phosphate (HPNP) order rate constants of HPNP-hydrolysis catalyzed by M3L and M3LH-1 were obtained, which indicated that Zn3LBH-1 was the most efficient catalyst among them. The proposed mechanisms included the activation of the substrate via binding to the metal ions and intramolecular nucleophilic attack by the deprotonated C2-hydroxyl of HPNP.