New 9- or 10-Arylpiperazinoalkyl Substituted Pyrimido- or Diazepino[2,1-f]purines with Partial or Full 5-HT1A Agonistic Activity.

Abstract 5HT 1A and 5HT 2A receptor affinities of several γ-(3'-chloro- or 2'-methoxyphenyl)-piperazinopropyl derivatives of pyrimido[2,1- f ]purines or 1,3-diazepino[2,1- f ]purines are reported. Some behavioral models demonstrated that 1,3-dimethyl-9-{3-[4-(2'-methoxyphenyl)-1-piperazinyl]propyl}-2,4-dioxo-1,3,6,7,8,9-hexahydropyrimido[2,1- f ]purine 5b and 1,3-dimethyl-9-{3-[4-(2'-methoxyphenyl)-1-piperazinyl]propyl}-2,4,8-trioxo-1,3-dihydro-9H-pyrimido[2,1- f ]purine 8b , may be classified as partial agonist and a full agonist, respectively of pre- and post-synaptic 5HT 1A receptors.