Semi-synthesis and proteasome inhibition of D-ring deoxy analogs of (-)-epigailocatechin gallate (EGCG), the active ingredient of green tea extract

摘要

A semi-synthetic route to the D-ring analogs of (-)-epigallocatechin gallate (EGCG) from the relatively abundant (-)-epigallocatechin (EGC), isolated from green tea leaves, is described. A natural product (13), found in Cistus salvifolius, its acetate (14) and analog (17) were synthesized by this method. Their inhibitory activities against proteasomes were investigated.