Piperine was used in this study in its raw form, and different steps, such as amide hydrolysis and amidation, were used to synthesize piperine derivatives containing a phenolic hydroxyl group. DPPH and ABTS free radical scavenging assays were used to assess piperine derivative antioxidant activities. We constructed an AAPH oxidative stress erythrocyte model to study the effect of piperine derivatives on the hemolysis rate of oxidatively damaged erythrocytes as well as the hemoglobin oxidation rate. This AAPH model was also used to determine piperine derivative effects on antioxidant enzyme activity and malondialdehyde (MDA) content. Results showed that spectroscopic methods could synthesize and identify piperine derivatives containing phenolic hydroxyl groups (H-1∼H-3). Moreover, DPPH and ABTS assay results showed that piperine derivative free radical clearance rates were higher compared with the parent compound. Additionally, piperine derivatives (H-1∼H-3) were found to provide protection to AAPH oxidatively damaged erythrocytes in their ability to inhibit AAPH-induced erythrocyte lysis, while hemoglobin oxidation was higher compared with the parent compound. Piperine derivatives may protect intracellular glutathione peroxidase (GSH-Px) antioxidant enzyme system activities, safeguarding against oxidative damage. This study synthesized novel piperine derivatives for use as potential antioxidant agent candidates.

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含酚羟基胡椒碱衍生物的合成及抗氧化活性

本研究使用原始形式的胡椒碱，并使用酰胺水解和酰胺化等不同步骤合成含有酚羟基的胡椒碱衍生物。DPPH 和 ABTS 自由基清除试验用于评估胡椒碱衍生物的抗氧化活性。我们构建了AAPH氧化应激红细胞模型，研究胡椒碱衍生物对氧化损伤红细胞溶血率和血红蛋白氧化率的影响。该 AAPH 模型还用于确定胡椒碱衍生物对抗氧化酶活性和丙二醛 (MDA) 含量的影响。结果表明，光谱方法可以合成和鉴定含有酚羟基的胡椒碱衍生物（H-1∼H-3）。而且，DPPH和ABTS测定结果表明胡椒碱衍生物自由基清除率高于母体化合物。此外，胡椒碱衍生物（H-1~H-3）被发现可以为 AAPH 氧化损伤的红细胞提供保护，因为它们具有抑制 AAPH 诱导的红细胞溶解的能力，而与母体化合物相比，血红蛋白的氧化程度更高。胡椒碱衍生物可以保护细胞内谷胱甘肽过氧化物酶 (GSH-Px) 抗氧化酶系统的活性，防止氧化损伤。该研究合成了新型胡椒碱衍生物，用作潜在的抗氧化剂候选物。胡椒碱衍生物 (H-1∼H-3) 被发现能够为 AAPH 氧化损伤的红细胞提供保护，因为它们具有抑制 AAPH 诱导的红细胞裂解的能力，而与母体化合物相比，血红蛋白的氧化程度更高。胡椒碱衍生物可以保护细胞内谷胱甘肽过氧化物酶 (GSH-Px) 抗氧化酶系统的活性，防止氧化损伤。该研究合成了新型胡椒碱衍生物，用作潜在的抗氧化剂候选物。胡椒碱衍生物 (H-1∼H-3) 被发现能够为 AAPH 氧化损伤的红细胞提供保护，因为它们具有抑制 AAPH 诱导的红细胞裂解的能力，而与母体化合物相比，血红蛋白的氧化程度更高。胡椒碱衍生物可以保护细胞内谷胱甘肽过氧化物酶 (GSH-Px) 抗氧化酶系统的活性，防止氧化损伤。该研究合成了新型胡椒碱衍生物，用作潜在的抗氧化剂候选物。