Venkatachalam S R, Salaskar A, Chattopadhyay A, Barik A, Mishra B, Gangabhagirathi R, Priyadarsini K I
Bio-Organic Division, Bhabha Atomic Research Centre, Mumbai 400 085, India.
Bioorg Med Chem. 2006 Sep 15;14(18):6414-9. doi: 10.1016/j.bmc.2006.05.042. Epub 2006 Jun 12.
A novel conjugate of melatonin 2 and alpha-lipoic acid 4 has been prepared using DCC mediated coupling. The conjugate named melatoninolipoamide has been assigned its structure 1 on the basis of spectral analysis (UV, IR, NMR, and EI-MS). Pulse radiolysis studies of the conjugate were carried out in aqueous solutions with both oxidizing and reducing radicals. The results indicate that the melatonin moiety of the conjugate reacts preferably with oxidizing radicals and the lipoic acid moiety exhibits preferential reaction with reducing radicals. The in vitro radioprotection ability of 1 was examined by gamma-radiation induced lipid peroxidation in liposomes and hemolysis of erythrocytes, and compared the results with those of melatonin and alpha-lipoic acid. The studies suggest that the conjugate can be explored as a probable radioprotector.
已使用二环己基碳二亚胺（DCC）介导的偶联反应制备了褪黑素2与α-硫辛酸4的新型共轭物。基于光谱分析（紫外、红外、核磁共振和电子轰击质谱），将该共轭物命名为褪黑素硫辛酰胺，并确定其结构为1。在含有氧化和还原自由基的水溶液中对该共轭物进行了脉冲辐解研究。结果表明，该共轭物的褪黑素部分优先与氧化自由基反应，而硫辛酸部分则表现出与还原自由基的优先反应。通过γ辐射诱导脂质体中的脂质过氧化和红细胞溶血来检测1的体外辐射防护能力，并将结果与褪黑素和α-硫辛酸的结果进行比较。研究表明，该共轭物有望作为一种辐射防护剂进行探索。
