Copper(II)-, Fe(III)-, Zn(II)-, and Mn(II)-3,5-di-iso-propylsalicylate (3,5-DIPS) chelates and Cu(II)2(acetyl-3,5-DIPS)4, and 3,5-DIPS, salicylidene Schiff base chelates Mn(III), Co(II), Ni(II), were kinetically examined as antioxidants in the scavenging of tert-butyl peroxyl radical ( $$tert - {\text{butylOO}}^{ \bullet }$$ ) in non-polar and polar aprotic solvents. Using kinetic EPR method absolute rate constants and corresponding Arrhenius parameters were determined for reactions of $$tert - {\text{butylOO}}^{ \bullet }$$ with these chelates in the temperature range from − 63 to − 11 °C. It was established that the order of anti- $$tert - {\text{butylOO}}^{ \bullet }$$ reactivity is: Mn(II)(3,5-DIPS)2 >> Cu(II)2(3,5-DIPS)4 > Fe(III)(3,5-DIPS)3 > Zn(II)(3,5-DIPS)2 >> Cu(II)2(acetyl-3,5-DIPS)4 and 3,5-DIPS acid. Mn(II)(3,5-DIPS)2 caused the most rapid removal rate for $$tert - {\text{butylOO}}^{ \bullet }$$ as a result of the oxidation of Mn(II) to Mn(III) by $$tert - {\text{butylOO}}^{ \bullet }$$ . The reaction of $$tert - {\text{butylOO}}^{ \bullet }$$ with Cu(II)2(3,5-DIPS)4, Zn(II)(3,5-DIPS)2 and Fe(III)(3,5-DIPS)3 is due only to hydrogen atom abstraction from the ligand phenolic OH group by $$tert - {\text{butylOO}}^{ \bullet }$$ , owing to their activation by the metalloelement through weakening the intramolecular hydrogen bond. High reactivity of $$tert - {\text{butylOO}}^{ \bullet }$$ with Mn(III) and Co(II) salicylidene Schiff base chelates was established. These salicylidene Schiff base chelates react in a 1:1 stoichiometric ratio with $$tert - {\text{butylOO}}^{ \bullet }$$ without free radical formation and with the single-electron oxidation of central metalloelements. It is concluded that removal of alkylperoxyl radical by Cu(II)-, Fe(III)-, Zn(II)-, and Mn(II)-3,5-di-iso-propylsalicylate chelates, Mn(III) and Co(II) salicylidene Schiff base chelates may partially account for their biological activities.

中文翻译：

---

3,5-二-异-丙基水杨酸盐​​和水杨基席夫碱的各种金属螯合物的抗过氧自由基反应的动力学EPR-研究

铜 (II)-、Fe(III)-、Zn(II)- 和 Mn(II)-3,5-二异丙基水杨酸 (3,5-DIPS) 螯合物和 Cu(II)2(乙酰- 3,5-DIPS)4 和 3,5-DIPS、水杨基席夫碱螯合物 Mn(III)、Co(II)、Ni(II)，作为抗氧化剂在清除叔丁基过氧自由基方面进行了动力学研究（$ $tert - {\text{丁基OO}}^{ \bullet }$$ ) 在非极性和极性非质子溶剂中。使用动力学 EPR 方法确定 $$tert - {\text{丁基OO}}^{ \bullet }$$ 与这些螯合物在 - 63 至 - 11 °C 的温度范围内的反应的绝对速率常数和相应的 Arrhenius 参数。已确定反$$tert - {\text{丁基OO}}^{ \bullet }$$ 反应性的顺序是：Mn(II)(3,5-DIPS)2 >> Cu(II)2( 3,5-DIPS)4 > Fe(III)(3,5-DIPS)3 > Zn(II)(3,5-DIPS)2 >> Cu(II)2(乙酰-3,5-DIPS)4和 3,5-DIPS 酸。锰(II)(3, 由于 $$tert 将 Mn(II) 氧化为 Mn(III)，5-DIPS)2 导致 $$tert - {\text{丁基OO}}^{ \bullet }$$ 的去除速度最快- {\text{丁基OO}}^{ \bullet }$$ 。$$tert - {\text{丁基OO}}^{ \bullet }$$ 与 Cu(II)2(3,5-DIPS)4、Zn(II)(3,5-DIPS)2 和 Fe 的反应(III)(3,5-DIPS)3 仅是由于 $$tert - {\text{butylOO}}^{ \bullet }$$ 从配体酚类 OH 基团中提取氢原子，因为它们被金属元素通过削弱分子内氢键。建立了 $$tert - {\text{丁基OO}}^{ \bullet }$$ 与 Mn(III) 和 Co(II) 水杨基席夫碱螯合物的高反应性。这些水杨基席夫碱螯合物以 1 的形式反应：1 化学计量比，$$tert - {\text{丁基OO}}^{ \bullet }$$ 没有自由基形成和中心金属元素的单电子氧化。得出结论，Cu(II)-、Fe(III)-、Zn(II)-和Mn(II)-3,5-二异丙基水杨酸盐​​螯合物、Mn(III)和Co去除烷基过氧自由基(II) 水杨基席夫碱螯合物可能部分解释了它们的生物活性。