3,4-Methylenedioxy-N-propargylamphetamine (abbreviated MDPL), also known as N-propargyl-MDA, is a synthetic substituted amphetamine and a lesser-known psychoactive compound. It was first synthesized by the American chemist Alexander Shulgin and is documented in his 1991 book PiHKAL (Phenethylamines I Have Known and Loved).
Chemical Properties
The compound has the molecular formula C₁₃H₁₅NO₂ and a molar mass of 217.26 g/mol. Its systematic IUPAC name is N-[1-(2H-1,3-benzodioxol-5-yl)propan-2-yl]prop-2-yn-1-amine. The structure consists of a 3,4-methylenedioxyphenyl group (a 1,3-benzodioxole ring) attached to a propylamine chain, with an N-propargyl substituent (–CH₂C≡CH) on the amine nitrogen. The hydrochloride salt forms white crystals with a melting point of 189–190 °C.
Synthesis
The synthesis, as described by Shulgin, involves reductive amination of 3,4-methylenedioxyphenyl-2-propanone (MDP2P) with propargylamine hydrochloride, using sodium cyanoborohydride as the reducing agent in methanol. The reaction proceeds under mildly acidic conditions over several days at ambient temperature. The freebase is obtained as an oil, which is then converted to the hydrochloride salt.
Pharmacology and Effects
According to Shulgin's anecdotal reports in PiHKAL, MDPL produced no significant central nervous system effects at oral doses up to 100 mg, and higher doses were not pursued due to the apparent lack of activity. The minimum dosage is listed as 150 mg, and the duration of action is unknown. The compound is described as causing few to no noticeable effects.
The N-propargyl moiety is structurally similar to that found in established monoamine oxidase inhibitors such as selegiline (N-propargylamphetamine), suggesting that MDPL may possess inhibitory effects on monoamine oxidase (MAO) enzymes. However, no specific biochemical assays, receptor binding data, or quantitative pharmacological studies for MDPL have been reported in peer-reviewed scientific literature.
Status
Very little data exists regarding the pharmacological properties, metabolism, or toxicity of MDPL. It has not been associated with widespread use, clinical studies, or regulatory scheduling in most jurisdictions. The compound remains an obscure research chemical documented primarily through Shulgin's phenomenological evaluations.
