Structure-activity relationship for a series of 2-substituted 1,2,3,4-tetrahydro-9H-pyrido[3,4-b]indoles: Potent subtype-selective inhibitors of (NMDA) receptors

A series of 2-substituted 1,2,3,4-tetrahydro-9H-pyrido[3,4-b]indoles was synthesized as potential antagonists for the NR1 /2B subtype of (NMDA) receptors. Assayed by electrical recording under steady-state conditions, 7-hydroxy-2-(4-phenylbutyl)-1,2,3,4-tetrahydropyrido-[3,4-b]indole (30) was the most potent compound in the series having an IC50 value of 50 nM at the NR1 /2B receptors.