153607-44-4Relevant articles and documents
Characterization of potent and selective antagonists at postsynaptic 5- HT(1A) receptors in a series of N4-substituted arylpiperazines
Peglion,Canton,Bervoets,Audinot,Brocco,Gobert,Le Marouille-Girardon,Millan
, p. 4044 - 4055 (2007/10/03)
Benzocycloalkyl and benzocycloalkenyl moities linked, directly or via an alkyl chain, to oxygen-bearing heteroarylpiperazines were synthesized, in an attempt to obtain potent and selective antagonists at postsynaptic 5-HT(1A) receptors. From the numerous arylpiperazines described in the literature, 1- (2,3-dihydro-1,4-benzodioxin-5-yl)piperazine (3a) was chosen as a model of an arylpiperazine in view of its selectivity for 5-HT(1A) receptors versus α1- , α2-, and β-adrenergic receptors, as well as dopamine D1 and D2 receptors. Two other closely-related arylpiperazines, 1-(1,5-benzodioxepin- 6-yl)piperazine (3b) and 1-(benzofuran-7-yl)piperazine (3c), were also examined in this study. All compounds showed high affinity at 5-HT(1A) sites (8.10 ≤ pK(i)s ≤ 9.35), and the majority behaved as antagonists in viva in blocking the hypothermia induced by the 5-HT(1A) agonist 8-OH-DPAT in the absence of a marked effect alone at equivalent doses. An in vivo evaluation of dopamine D2 receptor antagonist properties revealed that the majority of compounds was devoid of activity at this site, in marked contrast to BMY 7378 which displayed virtually no selectivity far 5-HT(1A) versus dopamine D2 receptors. Moreover, six compounds of the present series, 8, 10, 11, 14, 25, and, 37, showed > 10-fold selectivity in vitro for 5-HT(1A) versus α1- adrenergic receptors. Compound 14 displayed an optimal compromise between potency (pK(i) = 8.75), marked antagonist activity, and selectivity toward α1-adrenergic (81-fold) and dopamine D2 (195-fold) receptors. These characteristics clearly distinguish 14 from previously-reported ligands such as the postsynaptic 5-HT(1A) antagonist BMY 7378 and the weak partial agonist NAN 190 which, in contrast to the compounds of this series, belong to the well-exemplified class of imido derivatives of (o-methoxyphenyl)piperazines. The availability of 14 (S 15535) should facilitate the further elucidation of the functional role and potential therapeutic significance of 5-HT(1A) receptors.