4-MPD, also called 2-(ethylamino)-1-(p-tolyl)pentan-1-one, has the molecular formula: C14H21NO. Its molecular weight is 219.32 whilst its exact mass is 219.16. It ships as a powder with a stability rating of two years however acts as a stimulant in humans and animals, and is considered to be part of the cathinone class of legal stimulants. Rather than an analogue, 4-MPD is a higher homologue of both 4-Methylpentedrone (also called 4-Methyl-α-methylamino-valerophenone) and 4-Methylbuphedrone (also called 4-MeMABP). 4-MPD chemical is, however, a p-Methyl analogue for a chemical called Pentedrone.