And so we can have a variety of different types of competing reactions and competing products. And to basically minimize these unwanted products, we have to use two important agents. One of them is DCC, and that's an activating agent and it activates the carbon atom on the carboxyl group of the amino acid. So D stands for dye, c stands for cyclohexyl, and second, C stands for carbal diamide. And the blocking agent that we're going to use that essentially attaches and blocks the nitrogen on the amino group of that amino acid, es, tbock and B stands for butyl O stands for oxy. MC stands for Carbonal.