Design and synthesis of 2-[4-[4-(m-(ethylsulfonamido)-phenyl)piperazin-1-yl]butyl]-1,3-dioxoperhydropyrrolo[1,2-c]imidazole (EF-7412) using neural networks. A selective derivative with mixed antagonist properties

A test series of 32 phenylpiperazines III with affinity for -5-HT1A and α1 receptors was subjected to QSAR analysis using artificial neural networks (ANNs), in order to get insight into the structural requirements that are responsible for 5-HT1A/α1 selectivity. Good models and predictive power were obtained for 5-HT1A and α1 receptors. A comparison of these models gives information for the design of the new ligand EF-7412 (5-HT1A: Ki (nM)=27; α1: Ki (nM)> 1000). This derivative displayed affinity for dopamine D2 receptor (Ki=22 nM) and is selective for all other receptor examined (5-HT2A, 5-HT3, 5-HT4 and Bz). EF-7412 acts an antagonist in vivo in pre- and postsynaptic 5-HT1Areceptor sites and as an antagonist in dopamine D2 receptor.