| 15588097 |
Leopoldo M, Berardi F, Colabufo NA, Contino M, Lacivita E, Niso M, Perrone R, Tortorella V: Structure-affinity relationship study on N-(1,2,3,4-tetrahydronaphthalen-1-yl)-4-aryl-1-piperazinealkylamides, a new class of 5-hydroxytryptamine7 receptor agents. J Med Chem. 2004 Dec 16;47(26):6616-24.
A series of N-(1,2,3,4-tetrahydronaphthalen-1-yl)-4-aryl-1-piperazinealkylamides was prepared and their affinity for serotonin (5-hydroxytryptamine, 5-HT) 5-HT7, 5-HT (1A), and 5-HT (2A) receptors was measured by in vitro binding assays. In relation to 5-HT7 receptor affinity, receptor binding studies indicated that (i) the optimal alkyl chain length was five methylenes, (ii) an unsubstituted 1,2,3,4-tetrahydronaphthalenyl nucleus was preferred, and (iii) the substitution pattern of the aryl ring linked to the piperazine ring played a crucial role. Several compound with high affinity for 5-HT7 receptors were identified. Among them, 4-(2-methoxyphenyl)-N-(1,2,3,4-tetrahydronaphthalen-1-yl)-1-piperazinehexa namide (28), 4-(2-acetylphenyl)-N-(1,2,3,4-tetrahydronaphthalen-1-yl)-1-piperazinehexan amide (34), 4-(2-methylthiophenyl)-N-(1,2,3,4-tetrahydronaphthalen-1-yl)-1-piperazineh exanamide (44), 4-(2-hydroxyphenyl)-N-(1,2,3,4-tetrahydronaphthalen-1-yl)-1-piperazinehexa namide (46), and 4-(2-methylphenyl)-N-(1,2,3,4-tetrahydronaphthalen-1-yl)-1-piperazinehexan amide (49) were assayed for the 5-HT7 receptor-mediated relaxation of substance P-induced guinea pig ileum contraction. Compounds 28, 44, and 49 behaved as full agonists and compound 34 as a partial agonist, whereas derivative 46 acted as an antagonist. Among the compounds presented here, it emerged that 44 was identified as a potent 5-HT7 receptor agonist (Ki = 0.22 nM, EC50 = 2.56 microM), endowed with selectivity over 5-HT (1A) and 5-HT (2A) receptors (200-fold and > 1000-fold, respectively). |
34(0,1,1,4) |