1-Substituted-4-[3-(1,2,3,4-tetrahydro-5- or 7-methoxynaphthalen-1-yl)propyl]piperazines: influence of the N-1 piperazine substituent on 5-HT1A receptor affinity and selectivity versus D2 and alpha1 receptors. Part 6.
In the present paper, we report the synthesis and the binding profiles on 5-HT1A, D2, and alpha1 receptors of 1-substituted-4-[3-(5- or 7-methoxy-1,2,3,4-tetrahydronaphthalen-1-yl)propyl]piperazine derivatives 19-32 and some related heteroalkyl derivatives 33-35. The results obtained are compared to those previously reported for the 1-phenyl, 1-(2-methoxyphenyl), 1-(2-pyridyl) analogues 2-9. The results pointed out the critical role of the group linked in the N-1 position of the piperazine in terms of 5-HT1A binding affinity. In fact, 1-cyclohexyl, 1-(3-benzisoxazolyl), 1-(benzothiazole-2-carbonyl), 1-(2-benzothiazolyl), 1-(2-quinolyl) substituted piperazines 21-30 displayed moderate or low 5-HT1A receptor affinity; on the contrary, 1-(3-benzisothiazolyl) and 1-(1-naphthalenyl) substituted piperazines 19, 20 and 32 displayed high 5-HT1A receptor affinity, the Ki values being in the subnanomolar range. Furthermore, compounds 19, 20 and 32 demonstrated better selectivity over alpha1 receptors than the reference compounds 2-9.
Perrone
R
R
Dipartimento Farmaco-Chimico, Università degli Studi di Bari, Italy. perrone@farmchim.uniba.it
Berardi
F
F
Colabufo
N A
NA
Leopoldo
M
M
Tortorella
V
V
D000818:Animals; D001921:Brain / Q000378:metabolism; D008401:Gas Chromatography-Mass Spectrometry; D009682:Magnetic Resonance Spectroscopy; D010879:Piperazines / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D011869:Radioligand Assay; D051381:Rats; D018340:Receptors, Adrenergic, alpha-1 / Q000187:drug effects* / Q000378:metabolism; D017448:Receptors, Dopamine D2 / Q000187:drug effects* / Q000378:metabolism; D011985:Receptors, Serotonin / Q000187:drug effects* / Q000378:metabolism; D044263:Receptors, Serotonin, 5-HT1; D013329:Structure-Activity Relationship
D010879:Piperazines; D018340:Receptors, Adrenergic, alpha-1; D017448:Receptors, Dopamine D2; D011985:Receptors, Serotonin; D044263:Receptors, Serotonin, 5-HT1