摘要:
In the course of developing a metabolically stable M-3 receptor antagonist from the prototype antagonist, J-104129 (1), introduction of certain substituents into the cyclopentane ring of 1 was found to be effective not only in improving metabolic stability but also in greatly enhancing the subtype selectivity. Among the cyclopentane analogues, sulfonamide derivatives (10f) and (10g) displayed 160- and 310-fold selectivity for M-3 over M-2 receptors, and both were significantly more selective than the prototype antagonist (120-fold). Subsequent derivatization of the sulfonamide series led to the highly selective M-3 receptor antagonists (10h, 10i and 10j) with >490-fold selectivity for M-3 over M-2 receptors. Among them, p-nitrophenylsulfonamide (J-107320, 10h) exhibited 1 100-fold selectivity for M-3 receptors (K-i = 2.5 nM) over M-2 receptors (K-i = 2800 nM) in the human muscarinic receptor binding assay using [H-3]-NMS as a radio ligand. (C) 2000 Elsevier Science Ltd. All rights reserved.