Building Block for Gallic Acid Derivatives

It has been known that gallic acid derivatives found in tea leaves show antioxidative activity. Their anticancer action has also been intensively studied, and thus, a great deal of attention has been gained for the development of new pharmaceutical agents containing galloyl groups.

3,4,5-Tris(benzyloxy)benzoic acid (1) is a gallic acid, whose three hydroxyl functions are protected with benzyl groups. This derivative of gallic acid is a useful building block that can be incorporated into various organic molecules.¹⁾ As an example, Hudson et al. have developed a novel synthetic method to make HIV reverse transcriptase inhibitor, where chlomanol 2 was reacted with 1.²⁾ In another example, 1 has been utilized in the synthesis of polygalloyl-dendrimers as stable tannic acid mimics.³⁾