α-Pyrrolidinopentiophenone (also known as α-pyrrolidinovalerophenone, α-PVP, O-2387, β-keto-prolintane, prolintanone, or desmethylpyrovalerone) is a synthetic stimulant of the cathinone class developed in the 1960s that has been sold as a designer drug. Colloquially, it is sometimes called flakka.