title: Novel Amino-Pyridine Functionalized Chitosan Quaternary Ammonium Derivatives: Design, Synthesis, and Antioxidant Activity.
abstract: Chemical modification of chitosan is increasingly studied for its potential of providing new applications of chitosan. Here, a group of novel chitosan quaternary ammonium derivatives containing pyridine or amino-pyridine were designed and successfully synthesized through chemical modification of chitosan. Pyridine and amino-pyridine were used as functional groups to improve the antifungal activity of chitosan derivatives. The chitosan derivatives' antioxidant activity against hydroxyl-radical and 1,1-Diphenyl-2-picrylhydrazyl (DPPH)-radical was tested in vitro. The results showed that chitosan derivatives had better water solubility and stronger antioxidant activity compared with chitosan in all assays. Especially, compounds3Cand3E(with 3-amino pyridine and 2,3-diamino pyridine as substitute respectively) exhibited stronger hydroxyl-radical and DPPH-radical scavenging ability than other synthesized compounds. These data demonstrated that the synergistic effect of the amino group and pyridine would improve the antioxidant activity of chitosan derivatives, and the position of the amino group on pyridine could influence the antioxidant property of chitosan derivatives.
authors.affiliation: Key Laboratory of Coastal Biology and Bioresource Utilization, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, Shangdong, China. qli@yic.ac.cn.
authors.forename: Qing
authors.initials: Q
authors.lastname: Li
authors.affiliation: College of Chemistry, Chemical Engineering and Materials science, Shandong Normal University, Jinan 250014, Shandong, China. cafeapril@163.com.
authors.forename: Caili
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Coastal Biology and Bioresource Utilization, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, Shangdong, China. wqtan@yic.ac.cn.|University of Chinese Academy of Sciences, Beijing 100039, China. wqtan@yic.ac.cn.
authors.forename: Wenqiang
authors.initials: W
authors.lastname: Tan
authors.affiliation: Alliance Pharma, Inc., 17 Lee Boulevard, Malvern, PA 19355, USA. guguodong011@gmail.com.
authors.forename: Guodong
authors.initials: G
authors.lastname: Gu
authors.affiliation: Key Laboratory of Coastal Biology and Bioresource Utilization, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, Shangdong, China. zhanyongguo@hotmail.com.|University of Chinese Academy of Sciences, Beijing 100039, China. zhanyongguo@hotmail.com.
authors.forename: Zhanyong
authors.initials: Z
authors.lastname: Guo
mesh_terms: D000631:Aminopyridines / Q000138:chemical synthesis* / Q000737:chemistry; D000935:Antifungal Agents / Q000138:chemical synthesis* / Q000737:chemistry; D000975:Antioxidants / Q000138:chemical synthesis* / Q000737:chemistry; D001713:Biphenyl Compounds / Q000037:antagonists & inhibitors; D048271:Chitosan / Q000031:analogs & derivatives / Q000138:chemical synthesis*; D015195:Drug Design; D017665:Hydroxyl Radical / Q000037:antagonists & inhibitors; D010084:Oxidation-Reduction; D010851:Picrates / Q000037:antagonists & inhibitors; D000644:Quaternary Ammonium Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D012995:Solubility; D013329:Structure-Activity Relationship
chemical_list: D000631:Aminopyridines; D000935:Antifungal Agents; D000975:Antioxidants; D001713:Biphenyl Compounds; D010851:Picrates; D000644:Quaternary Ammonium Compounds; D017665:Hydroxyl Radical; D048271:Chitosan; C004931:1,1-diphenyl-2-picrylhydrazyl
keywords: amino-pyridine; antioxidant activity; chemical modification; chitosan derivatives