Selective DAT/NET releasing activity of α-methylated phenethylamines in a modified HEK-293 uptake assay.
We characterise a series of eleven α-methyl-substituted phenethylamines (NGP-107-a to k) in an in vitro monoamine uptake assay using HEK-293 cells stably transfected with human DAT, NET, or SERT. Compounds were profiled for IC50 potency, cytotoxicity (MTS, 48 h) and selectivity ratios. Lead compound NGP-107 exhibited IC50(DAT) = 118 ± 12 nM, IC50(NET) = 89 ± 9 nM and IC50(SERT) > 4,200 nM, establishing a > 35-fold selectivity window over the serotonergic system. In parallel MAO-A microsomal assays, α-methylation reduced MAO-mediated turnover by 71 % relative to reference d-amphetamine, consistent with the hypothesised backbone stabilisation.