HDEP-28 or Ethylnaphthidate is a piperidine based stimulant drug, closely related to Ethylphenidate, but with the benzene ring replaced by naphthalene. HDEP-28 is even more closely related to HDMP-28, which acts as a potent serotonin–norepinephrine–dopamine reuptake inhibitor with several times the potency of Methylphenidate and a short duration of action. HDEP-28 (Ethylnaphthidate) is a new research chemical with the IUPAC or formal name of ethyl 2-(naphthalen-2-yl)-2-(piperidin-2-yl)acetate, chemical formula of C19H23NO2, and a molecular mass of 297.40.