A series of indole-2-carboxylates bearing suitable chains at the C-3 position of the indole nucleus was synthesized and evaluated in terms of in vitro affinity using [3H] glycine binding assay and in vivo potency by inhibition of convulsions induced by N-methyl-d-aspartate (NMDA) in mice. 3-[2-[(Phenylamino) carbonyl] ethenyl]-4, 6-dichloroindole-2-carboxylic acid (8) was an antagonist at the strychnine-insensitive glycine binding site ( ...