Hatay Mustafa Kemal University, Faculty of Arts and Sciences, Department of Chemistry, Hatay, Turkey.
Hatay Mustafa Kemal University, Faculty of Agriculture, Department of Field Crops, Hatay, Turkey.
Carbohydr Polym. 2020 Jul 15;240:116333. doi: 10.1016/j.carbpol.2020.116333. Epub 2020 Apr 25.
In this work, two new chitosan-Schiff base derivatives (HCS-GSP and LCS-GSP) were synthesized by the condensation reaction of high molecular weight chitosan (HCS) and low molecular weight chitosan (LCS) with (-)-gossypol (GSP), respectively. For this purpose, racemic gossypol was isolated from cotton seeds and it was further enantiomerically purified by diastereomeric resolution technique using l-tryptophan methyl ester hydrochloride. Then, chitosan polymers were derivatized with (-)-gossypol by the condensation reaction. The isolated and synthesized coumpounds were characterized by physical measurements and spectroscopic methods (elemental analysis C,H,N, Uv-vis, FT-IR, H&C NMR and TG/DTG/DTA). The antioxidant activity of high molecular weight chitosan (HCS), low molecular weight chitosan (LCS) and their gossypol derivatives was evaluated as radical scavengers against 1,1-diphenyl-2-picrylhydrazyl radicals (DPPH). The results showed that both of the chitosan-gossypol derivatives (HCS-GSP and LCS-GSP) had a better ability to scavenging DPPH radical (IC, 12 μg/mL and 16 μg/mL, respectively) than its unmodified chitosan.
在这项工作中，通过高分子量壳聚糖 (HCS) 和低分子量壳聚糖 (LCS) 与 (-)-棉酚 (GSP) 的缩合反应，分别合成了两种新的壳聚糖-Schiff 碱衍生物 (HCS-GSP 和 LCS-GSP)。为此，从棉籽中分离出消旋棉酚，并进一步通过使用 l-色氨酸甲酯盐酸盐的非对映体拆分技术对其进行对映体纯 化。然后，壳聚糖聚合物通过缩合反应与 (-)-棉酚进行衍生化。通过物理测量和光谱方法（元素分析 C、H、N、Uv-vis、FT-IR、H 和 C NMR 以及 TG/DTG/DTA）对分离和合成的化合物进行了表征。作为 1,1-二苯基-2-苦基肼自由基 (DPPH) 的自由基清除剂，评估了高分子量壳聚糖 (HCS)、低分子量壳聚糖 (LCS) 和它们的棉酚衍生物的抗氧化活性。结果表明，两种壳聚糖-棉酚衍生物 (HCS-GSP 和 LCS-GSP) 都具有更好的清除 DPPH 自由基的能力 (IC50，分别为 12 μg/mL 和 16 μg/mL)，优于其未修饰的壳聚糖。
