2,4-Dinitrophenol (2,4-DNP or simply DNP) is an organic compound with the formula HOC6H3(NO2)2. It is a yellow, crystalline solid that has a sweet, musty odor. It sublimes, is volatile with steam, and is soluble in most organic solvents as well as aqueous alkaline solutions. It is a precursor to other chemicals and is biochemically active, inhibiting energy (adenosine triphosphate, ATP) production in cells with mitochondria. Its use in high doses as a dieting aid has been identified with severe side-effects, including a number of deaths.