A similar chemical analog of methamphetamine is N, alpha-Diethylphenethylamine or N, alpha-Diethylphenylethylamine (N, alp-DEPEA). It was initially patented as one of the analogs for pharmaceutical applications by Knoll Pharma. These analogs demonstrated cognitive enhancement properties and improved pain tolerance in animal models. This class of compounds, however, has never been formulated into a drug. N, al-DEPEA has not been tested in humans, but it is predicted to be less potent than methamphetamine but greater than ephedrine by experts including Pieter Cohen, an assistant professor of medicine at Harvard Medical School.