N1-(Dimethoxytrityl)-D-(+)biotin 2-Nitrophenyl Ester is a derivative of Biotin (B389040), which is a growth factor present in minute amounts in every living cell. Biotin plays an indispensable role in numerous naturally occurring carboxylation reactions. It occurs mainly bound to proteins or polypeptides. The richest sources of biotin are liver, kidney, pancreas, yeast, and milk. The biotin content of cancerous tumors is higher than that of normal tissue. Molecular Formula: C37H37N3O7S Molecular Weight: 667.77