Synthesis and pharmacological evaluation of new 5-(cyclo)alkyl-5-phenyl- and 5-spiroimidazolidine-2,4-dione derivatives. Novel 5-HT1A receptor agonist with potential antidepressant and anxiolytic activity.

The synthesis of 5-(cyclo)alkyl-5-phenyl- and 5-spiroimidazolidine-2,4-dione derivatives with an arylpiperazinylpropyl moiety (12-23) and their in vitro and in vivo pharmacological properties and molecular characteristics were described. The investigated compounds exhibited high affinity for 5-HT(1A) (13-22) and 5-HT(2A) (18, 20, 21, 23) receptors and diversified pharmacological profile. Compounds 17, 20 and 22 showed antagonistic, partial agonistic and agonistic activity, respectively, toward 5-HT(1A) receptor and they were investigated as potential antidepressants and/or anxiolytics.

Synthesis and preliminary pharmacological evaluation of imidazo[2,1-f]purine-2,4-dione derivatives.

A series of N-8-arylpiperazinylpropyl derivatives of 1,3-dimethyl-(1H,8H)-imidazo[2,1-f]purine-2,4-dione (2-10) and amide derivatives of 1,3-dimethyl-6,7-dihydroimidazo[2,1-f]purine-2,4-(1H,3H)-dione-7-carboxylic acid (11-13) were synthesized. Compounds (2-10) evaluated in vitro were potent 5-HT(1A) receptor ligands. Preclinical studies indicated that 8-[3-(N4-phenyl)-piperazin-N1-yl-propyl]-1,3-dimethyl-(1H,8H)-imidazo[2,1-f]purine-2,4-dione (2) exerts anxiolytic-like activity in the four-plate test in mice; however its effect was weaker, than that produced by Diazepam.

The influence of modifications in imide fragment structure on 5-HT(1A) and 5-HT(7) receptor affinity and in vivo pharmacological properties of some new 1-(m-trifluoromethylphenyl)piperazines.

New, flexible (7, 9, 11 and 13) and rigid (8, 10, 12 and 14) imides with a 1-(m-trifluorophenyl)piperazine fragment and a tetramethylene or a 1e,4e-cyclohexylene spacer, respectively, showed very high affinity (K(i)=0.3-34 nM) and agonistic in vivo activity for 5-HT(1A) receptors. Flexible new compounds and the previously described 5 also bound to 5-HT(7) receptors (K(i)=21-134 nM).

7-Arylpiperazinylalkyl and 7-tetrahydroisoquinolinylalkyl derivatives of 8-alkoxy-purine-2,6-dione and some of their purine-2,6,8-trione analogs as 5-HT(1A), 5-HT(2A), and 5-HT(7) serotonin receptor ligands.

On the basis of our earlier studies with the serotonin receptor ligands in the group of 1,3-dimethyl-3,7-dihydropurine-2,6-dione derivatives, a series of new arylpiperazinylalkyl and tetrahydroisoquinolinylalkyl analogs of 8-alkoxy-1,3-dimethyl-3,7-dihydropurine-2,6-dione (10-25) and 1,3-dimethyl-7,9-dihydro-3H-purine-2,6,8-trione (26-30) were synthesized and their 5-HT(1A), 5-HT(2A), and 5-HT(7) receptor affinities were determined. The new compounds 17, 18, 20, and 21 were found to be highly active 5-HT(1A) receptor ligands (K(i)=11-19nM) with diversified affinity for 5-HT(2A) receptors (K(i)=15-253nM). Compounds 12, 13, 15, and 19 were moderately potent 5-HT(2A) ligands (K(i)=23-57nM), whereas 17, 18, 24, and 25 showed distinct affinity for 5-HT(7) receptors (K(i)=51-83nM).

Novel class of arylpiperazines containing N-acylated amino acids: their synthesis, 5-HT1A, 5-HT2A receptor affinity, and in vivo pharmacological evaluation.

Novel arylpiperazines with N-acylated amino acids, selected on the basis of a preliminary screening of two libraries previously synthesized on SynPhase Lanterns, were prepared in solution and their affinity for 5-HT(1A), 5-HT(2A), and D(2) receptors was evaluated. The compounds bearing (3-acylamino)pyrrolidine-2,5-dione (19-26) and N-acylprolinamide (29-34) moieties showed high affinity for 5-HT(1A) (K(i)=3-47 nM), high-to-low for 5-HT(2A) (K(i)=4.2-990 nM), and low for D(2) receptors (K(i)=0.