Spiro-imidazo[1,2-a]indeno[1,2-e]pyrazine-4-one derivatives are mixed AMPAand NMDA glycine-site antagonists active in vivo.

Original spiro-imidazo[1,2-a]indeno[1,2-e]pyrazine-4-one derivatives were s ynthesised and led to the identification of 3e which showed good affinities for both the AMPA and the NMDA glycine-site receptors, and displayed good anticonvulsant effects after i.p. and i.v. administrations in the electrosh ock-induced convulsion assay in mice. The corresponding dextrorotatory isom er (+)-3e was notably more potent than the levorotatory isomer (-)-3e in in vitro and in vivo assays. (C) 1999 Elsevier Science Ltd. All rights reserv ed.