We report the first study on the electronic effects of ortho-substituents in dendritic antioxidants. Six antioxidants were designed to contain a common phenol ring to provide a baseline antioxidant activity, attached to two other phenol rings with H atoms (reference compound), electron donating groups (EDGs), or electron withdrawing groups (EWGs) ortho to the phenolic OH. These antioxidants were synthesized via reductive amination. Based on the DPPH assay, EDGs (o-OCH₃) strongly enhanced while EWGs (o-NO₂) significantly decreased the antioxidant activity. The halogens (o-Cl and o-Br) did not show any significant effect.

中文翻译：

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树突状抗氧化剂中邻苯酚取代基的电子（作用或撤除）作用

我们报告的电子效果的第一项研究中邻树突抗氧化剂-取代。六种抗氧化剂被设计成含有一个共同的酚环，以提供基线的抗氧化活性，附连到另外两个酚环用H原子（参考化合物），给电子基团（电子讨论组），或吸电子基团（专家工作组）的邻位的酚OH 。这些抗氧化剂是通过还原胺化合成的。根据DPPH分析，EDG（o -OCH ₃）显着增强，而EWG（o -NO ₂）显着降低抗氧化活性。卤素（o -Cl和o-Br）没有显示任何明显的影响。