Novel epigallocatechin gallate tetramer and vascular endothelial function improving agent containing them

摘要

To provide a compound which can be ingested continuously and has an action of improving vascular endothelial function by enhancing the action of NO from vascular endothelial cells. A compound represented by the formula (I) (wherein R1, R2, R3 and R4 are each H or a gallate group) or a salt thereof, and a vascular endothelial function improving agent, food or drink containing the compound Or a pharmaceutical composition.