A novel series of 2-(3-indolyl)alkylamino-1-(3-chlorophenyl)ethanols was prepared and evaluated for in vitro ability to stimulate cAMP production in Chinese hamster ovary cells expressing cloned human beta(3)-AR. The optically active 30a was found to be the most potent and selective human beta(3)-AR agonist in this series with an EC(50) value of 0.062nM. In addition, 30a selectivity for human beta(3)-AR
An indole derivative of the formula:
wherein R1 is lower alkoxy, lower alkoxycarbonyl-lower alkoxy, carboxy-lower alkoxy , lower alkoxycarbonyl, phenyl-lower alkoxy, lower alkyl being optionally substituted by hydroxy, di-lower alkylaminosulfonyl, etc., R2 is hydrogen, halogen, lower alkoxy, lower alkoxycarbonyl-lower alkoxy, carboxy-lower alkoxy, etc., R3 is hydrogen or lower alkyl, R4 is halogen or trifluoromethyl, R5 is lower alkyl, or a salt thereof, these compounds being potent β3-adrenergic receptor-stimulating agent with excellent adrenoceptor selectivity, and being useful in the prophylaxis or treatment of obesity or diabetes mellitus.