Department of Biochemistry and Medical Chemistry, Medical School, University of Pécs, Szigeti út 12, H-7624 Pécs, Hungary.
Department of Pharmacognosy, Faculty of Pharmacy, University of Pécs, Rókus u. 2, H-7624 Pécs, Hungary.
Molecules. 2022 Jul 28;27(15):4822. doi: 10.3390/molecules27154822.
Carotenoid succinates were synthesized from hydroxy carotenoids and were coupled to a commercially available derivative of melatonin via amide bond for producing more powerful anti-oxidants and yet new hybrid lipophilic bifunctional molecules with additional therapeutic effects. The coupling reactions produced conjugates in acceptable to good yields. Succinylation increased the water solubility of the carotenoids, while the conjugation with melatonin resulted in more lipophilic derivatives. The conjugates showed self-assembly in aqueous medium and yielded relatively stable colloidal solutions in phosphate-buffered saline. Antioxidant behavior was measured with ABTS and the FRAP methods for the carotenoids, the carotenoid succinates, and the conjugates with melatonin. A strong dependence on the quality of the solvent was observed. TEAC values of the new derivatives in phosphate-buffered saline were found to be comparable to or higher than those of parent carotenoids, however, synergism was observed only in FRAP assays.
类胡萝卜素琥珀酸酯是由羟基类胡萝卜素合成的，并通过酰胺键与一种市售的褪黑素衍生物偶联，以产生更有效的抗氧化剂和具有额外治疗效果的新型混合亲脂双功能分子。偶联反应以可接受至良好的收率得到了轭合物。琥珀酰化增加了类胡萝卜素的水溶性，而与褪黑素的结合则导致了更亲脂的衍生物。这些轭合物在水介质中自组装，并在磷酸盐缓冲盐水中生成相对稳定的胶体溶液。使用 ABTS 和 FRAP 方法测量了类胡萝卜素、类胡萝卜素琥珀酸酯和与褪黑素结合的轭合物的抗氧化行为。观察到抗氧化行为强烈依赖于溶剂的质量。在磷酸盐缓冲盐水中，新衍生物的 TEAC 值与母体类胡萝卜素相当或更高，但仅在 FRAP 测定中观察到协同作用。
