Structure of the condensed tannins, flavan-3-ol monomer units, and substrates of tyrosinase.

<p>(<b>1</b>) Chemical structure of the condensed tannins. The 4 to 6 linkage (dotted line) is an alternative interflavan bond. The terminal unit is at the bottom the multi-unit structure. (<b>2</b>) Structure similarities between the flavan-3-ol monomer units and the substrates of tyrosinase.</p>