Six 3-hydroxymethyl-7-(N-substituted aminosulfonyl)-1, 2, 3, 4-tetrahydroisoquinolines (16- 21) were synthesized and evaluated for their phenylethanolamine N-methyltransferase (PNMT) inhibitory potency and affinity for the α2-adrenoceptor. The addition of nonpolar substituents to the sulfonamide nitrogen of 9 (3-CH2OH-7-SO2NH2-THIQ) led to inhibitors (16-21) that have high PNMT inhibitory potency and high selectivity, and most of these (16 ...