title: Targeted acylation for all the hydroxyls of (+)-catechin and evaluation of their individual contribution to radical scavenging activity.
abstract: The reactivity profile of all the hydroxyl groups in (+)-catechin towards acylation and their respective contribution to radical scavenging activity were systematically explored in this work. Selective acylation of the hydroxyls on different rings was carried out employing either a basic or acidic activation strategy. Monoacylation of B ring was achieved effectively with the aid of dimethyltin dichloride. Monoacylation of A ring was accomplished by sequential protection and deprotection of B and C rings. Based on specific acylation of all the individual hydroxyls of (+)-catechins, the structure radical scavenging activity relationship of each hydroxyl of (+)-catechin was established. It was demonstrated that the vicinal phenolic hydroxyls on B ring played the most important role in the ABTS radical scavenging activity and those on A and C rings made a much smaller contribution. This study has laid solid groundwork for further modification of the catechins and improvement of their properties.
authors.affiliation: Department of Food Science and Nutrition, Fuli Institute of Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang R&D Center for Food Technology and Equipment, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, China.
authors.forename: Shan
authors.initials: S
authors.lastname: Hong
authors.affiliation: Department of Food Science and Nutrition, Fuli Institute of Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang R&D Center for Food Technology and Equipment, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, China. Electronic address: songbailiu@zju.edu.cn.
authors.forename: Songbai
authors.initials: S
authors.lastname: Liu
mesh_terms: D000215:Acylation; D002392:Catechin / Q000737:chemistry*; D016166:Free Radical Scavengers / Q000737:chemistry*; D017665:Hydroxyl Radical / Q000737:chemistry*; D010636:Phenols / Q000737:chemistry; D013329:Structure-Activity Relationship
chemical_list: D016166:Free Radical Scavengers; D010636:Phenols; D017665:Hydroxyl Radical; D002392:Catechin
keywords: Acylation; Antioxidant activity; Catechin; Hydroxyl; Radical scavenging activity