Synthesis and pharmacological evaluation of carboxamide derivatives as selective serotoninergic 5-HT(4) receptor agonists.
A number of new carboxamide derivatives were synthesized. The affinity of these compounds for the serotoninergic 5-HT(4) receptor was evaluated by use of radioligand-binding techniques. The agonistic activity was evaluated as the contractile effect of the ascending colon isolated from guinea-pigs. Among these compounds, 4-amino-5-chloro-2-methoxy-N-[1-[2-[(methylsulfonyl)amino]ethly]-4-piperidinylmethyl]benzamide (24) showed a high affinity for the 5-HT(4) receptor (Ki = 9.6 nM). Compound 24 displayed a higher affinity for 5-HT(4) receptors than the other receptors, including, 5-HT(3) and dopamine D(2) receptors. In addition, compound 24 was confirmed to be a potent 5-HT(4) receptor agonist (ED(50) = 7.0 nM). An interaction model between compound 24 and 5-HT(4) receptor was proposed.
Itoh
K
Research Laboratories, Yoshitomi Pharmaceutical Industries Ltd., 955 Koiwai, Yoshitomi-cho, Chikujo-gun, 871-8550, Fukuoka, Japan
Kanzaki
K
Ikebe
T
Kuroita
T
Tomozane
H
Sonda
S
Sato
N
Haga
K
Kawakita
T