Identification and quantification of hydroxycinnamoylated catechins in tea by targeted UPLC-MS using synthesized standards and their potential use in discrimination of tea varieties

The contents of hydroxycinnamoylated catechins (HCCs) in tea leaves have yet to be thoroughly investigated. Herein, four HCCs, (−)-epicatechin 3-O-p-coumaroate (EC-pC), (−)-epicatechin 3-O-caffeoate (EC-C), (−)-epigallocatechin 3-O-p-coumaroate (EGC-pC), and (−)-epigallocatechin 3-O-caffeoate (EGC-C) were synthesized as standards through an improved route and then identified in leaves of 40 and quantified in 20 tea cultivars using...