Nicotinamide-15N,13C3 is the 13C-labeled and 15N-labeled Nicotinamide. Nicotinamide is a form of vitamin B3 that plays essential roles in cell physiology through facilitating NAD+ redox homeostasis and providing NAD+ as a substrate to a class of enzymes that catalyze non-redox reactions. Nicotinamide is an inhibitor of SIRT1.