Creatine

Creatine, a substance of composition C₄H₉N₃O₂, which is found in the muscles of all vertebrate animals, and to a smaller extent in the nerves and blood. It may be obtained from flesh or "meat extract" by digestion with water and subsequent purification. It forms monoclinic crystals, which are slightly soluble in cold, and readily in boiling, water. By evaporating the solution with an acid, a substance creatinine is obtained (C₄H₇N₃0), which is found in urine.