The Syntheses,Chelating And Antioxidant Capabilities Research Of Fullerene-based Catechol Derivatives

The chemical toxicities of radionuclides are harmful to human health after introduced into living system through inhalation or wounds,which makes radionuclides decorporation be a research hot spot in medicinal chemistry.However,decorporation agents ignore the damage of internal exposure which produce harmful free radicals to damage and oxidize cells,and even lead to cancer and gene mutations.Catechol ligands show excellent properties,low toxicity and high efficiency in so many complexing agents,and C60 is known as the "free radical sponge".Therefore,we synthesized and chose the excellent catechol ligands bound to fullerene with the expectation of bifunctional chelators of complexation and antioxidation.Here are two parts in the study.The one is the syntheses,complexation and antioxidant properties of 1,3-dicarbonyl biscatechol ligands.Using2,3-dihydroxybenzoic acid and alcoholamine or diamide as raw materials,three1,3-dicarbonyl biscatechol ligands were synthesized through reactions of benzylation,amidation,etc.And the structures were verified by characterization.The complexation properties of biscatechol ligands with uranyl,copper and zinc ions were determined by spectrophotometric titration,and chose the catechol ligands with great performance for the preparation of fullerene multi-addition derivatives.The results show that the complexing abilities for uranyl ion were log ?121 ? 34.55,pUO₂ ? 20.68,and for copper ion and zinc ion were pCu ? 15.06 and pZn ? 8.13,which indicated that the ligands could chelate uranyl ions effectively and have a selectivity for metal ions.The another one is the syntheses,complexation and antioxidant properties of fullerene multi-catechol derivatives.Using C60,iodine monochloride and excellent benzamide intermediates as raw materials,fullerene multi-catechol derivatives were synthesized by synthesis of hexachlorofullerene,debenzylation and substitution of C60Cl6,and the structures were verified by characterization.The complexation properties with simulated nuclide cerium ion???were determined by fluorescence spectroscopy,and the antioxidant properties were assessed through modified DPPH· method.The results show that thewater-soluble derivatives?> 150 mg/m L?can chelate cerium ion???with the conditional stability constants log KSV ? 5.30 and scavenge more than 2.14 eq.DPPH radicals.