Structure−Activity Relationship of Quinoline Derivatives as Potent and Selective α<sub>2C</sub>-Adrenoceptor Antagonists
作者:Iisa P. J. Höglund、Satu Silver、Mia T. Engström、Harri Salo、Andrei Tauber、Hanna-Kaisa Kyyrönen、Pauli Saarenketo、Anna-Marja Hoffrén、Kurt Kokko、Katariina Pohjanoksa、Jukka Sallinen、Juha-Matti Savola、Siegfried Wurster、Oili A. Kallatsa
DOI:10.1021/jm060262x
日期:2006.10.1
Starting from two acridine compounds identified in a high-throughput screening campaign (1 and 2, Table 1), a series of 4-aminoquinolines was synthesized and tested for their properties on the human alpha(2)-adrenoceptor subtypes (alpha(2A), alpha(2B), and alpha(2C.)). A number of compounds with good antagonist potencies against the alpha(2C)-adrenoceptor and excellent subtype selectivities over the other two subtypes were discovered. For example, (R)-4-[4-(3,4-dimethylpiperazin-1-yl) phenylamino] quinolin- 3- yl} methanol 6j had an antagonist potency of 8.5 nM against, and a subtype selectivity of more than 200-fold for, the alpha(2C)-adrenoceptor. Investigation of the structure-activity relationship identified a number of structural features, the most critical of which was an absolute need for a substituent in the 3-position of the quinoline ring. The 3-position on the piperazine ring was also found to play an appreciable role, as substitutions in that position exerted a significant and stereospecific beneficial effect on the alpha(2C)-adrenoceptor affinity and potency. Replacing the piperazine ring proved difficult, with 1,4-diazepanes representing the only viable alternative.