Total synthesis of theaflavins

• Main Authors: Chien-Chung Chu, 朱建宗
• Other Authors: Yean-Jang Lee
• Format: Others
• Language: zh-TW
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/63719384164888655097

碩士 === 國立彰化師範大學 === 化學系 === 92 === Abstract Theaflavin was found in the natural product, black tea, and it was oxidatively synthesized by (-)-epigallocatechin and (-)-epicatechin which was isolated from green tea. Because of theaflavins in low abundance of black tea and challenging purification procedure, but they have many biological activities. Therefore, it was recently attracted by many chemists to synthesize the theaflavins. These natural products have been synthesized by methods including using oxidative reagent of K3Fe(CN)6、polyphenoloxidase (PPO) 、Plant Homogenates and peroxidase (POD) to combine pyrogallols (gallocatechins and gallic acid) and catechols (catechins) . However they were poor yields. Now we present to synthesize theaflavin in another route. In our experiments, we synthesized a lot of precursors of the theaflavins, and then synthesized the theflavins further more. We found the best yield of these precursors with 4-bromocatecol and gallic acid. Finally, we synthesized theaflavic acid, then it can use to further synthesize theaflavins.