Butylone, also known as β-keto-N-methylbenzodioxolylbutanamine (βk-MBDB), is an entactogen, psychedelic, and stimulant psychoactive drug of the phenethylamine chemical class. It is the β-keto (substituted cathinone) analogue of MBDB and the substituted methylenedioxyphenethylamine analogue of buphedrone.

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