Chemical and Pharmaceutical Bulletin p. 1611 - 1622 (2000)
Update date:2022-09-26
Topics:
Mandelli, Giacomina R.
Maiorana, Stefano
Terni, Patrizia
Lamperti, Giuseppina
Colibretti, Maria Luisa
Imbimbo, Bruno P.
A series of 5H-dibenz[b,f]azepine derivatives was prepared and evaluated for binding affinities to muscarinic receptors in vitro. Among them, compound 8 showed a high affinity for human recombinant M2 receptors (K(i)=2.6 nM), a low affinity for M4 receptors (39-fold less than for M2 receptors) and a very low affinity for M1 and M3 receptors (119- and 112-fold less than for M2 receptors, respectively). The high M2 selectivity of 8 may be attributed to the olefinic bond of the azepine ring. Functional experiments showed 8 to be a competitive antagonist with high affinity to the cardiac (pA2=7.1) and low affinity to the intestinal muscarinic receptors (IC50=0.54 μM). In vivo experiments confirmed the in vitro M2 selectivity of 8. Acetylcholine-induced bradycardia was dose-dependently antagonized in rats after both intravenous and intraduodenal administration of 8. In rats, cholinergic functions mediated by M1 or M3 receptors (salivary secretion, pupil diameter, gastric emptying, intestinal transit time) were not affected by the oral administration of 8 even at doses as high as 30 times the antibradycardic effective dose. Furthermore, 8 had no analgesic activity in mice, indicating poor central nervous system penetration. In dogs, nocturnal bradycardia was dose-dependently inhibited by the oral route with a duration of action of about 24h. Compound 8 appears to be a promising cardioselective antimuscarinic agent for the treatment of dysfunctions of the cardiac conduction system such as sinus or nodal bradycardia ('sick-sinus syndrome') and atrioventricular block.
View MoreShanghai Maxchemco Chemical Industry Co., Ltd.
Contact:(86)21-51079223
Address:No.1305-8, B241, the Ecust Park, Huajing Road, Xuhui District, Shanghai
MTT Pharma & Bio-technology Co.,Ltd(expird)
Contact:+86-21-58407925
Address:Room2019, Building C, Tomson Center, No.158, Zhang Yang Road, Shanghai, China
Jiangsu Dacheng Pharmaceutical and Chemical Co.,Ltd
Contact:+86-0517-87036900
Address:Chuzhou Chemical park, Huai'an, Jiangsu Province
Shanghai Micro-mega Industry Co., Ltd.
Contact:0086-21-34628682;57153848
Address:Rm413,No.413,West Meilong Road, Minhang District,Shanghai P R China
Shanghai united Scientific Co.,Ltd.
Contact:+86-21-53535353
Address:28F No.900 huaihai Road Shanghai China
Doi:10.1021/ja005570d
(2000)Doi:10.1007/BF00954344
(1983)Doi:10.1021/om000562r
(2000)Doi:10.1039/C29710000215
()Doi:10.1039/a905018c
(1999)Doi:10.1016/S0040-4039(00)01491-X
(2000)