Atropisomeric 3-(β-hydroxyethyl)-4-arylquinolin-2-ones as Maxi-K Potassium Channel Openers
摘要:
The synthesis of a series of 3-beta-hydroxyethyl-4-arylquinolin-2-ones is described. These compounds contain hydrophilic and hydrophobic substituents ortho to the phenolic OH in the C ring of the quinolinone. Electrophysiological evaluation of the panel of compounds revealed that 11 and 16 with an unbranched ortho substituent retain activity as maxi-K ion channel openers. Members of this series of compounds can exist as stable atropisomers. Calculated estimates of the energy barrier for rotation around the aryl-aryl single bond in 3 is 31 kcal/mol. The atropisomers of (+/-)-3, (+/-)-4, and (+/-)-11 were separated by chiral HPLC and tested for their effect on maxi-K mediated outward current in hSlo injected X. laevis oocytes. The (-) isomer in each case was found to be more active than the corresponding (+) isomer, suggesting that the ion channel exhibits stereoselective activation. X-ray crystallographic structures of (+)-3 and (+)-11 were determined. Evaluation of the stability of (-)-3 at 80 degrees C in n-butanol indicated a 19.6% conversion to (+)-3 over 72 h. In human serum at 37 degrees C (-)-3 did not racemize over the course of the 30 h study.
Analogs of a potent maxi-K potassium channel opener with an improved inhibitory profile toward cytochrome P450 isozymes
作者:Vivekananda M. Vrudhula、Bireshwar Dasgupta、Christopher G. Boissard、Valentin K. Gribkoff、Kenneth S. Santone、Richard A. Dalterio、Nicholas J. Lodge、John E. Starrett
DOI:10.1016/j.bmcl.2005.06.056
日期:2005.10
Quinolinone 1 is a potent maxi-K potassium channel opener. In an effort to design analogs of I with a better inhibitory profile toward the CYP2C9 isozyme, the two acidic sites were chemically modified independently to generate a number of analogs. These analogs were evaluated as maxi-K channel openers in vitro using Xenopus laevis oocytes expressing cloned hSlo maxi-K channels. Compounds 15, 17, and 19 showed potent activity as maxi-K channel openers and were further evaluated for inhibition of the activity of the CYP2C9 isozyme. Compounds 17 and 19 showed diminished inhibitory potency against 2C9 and also against a panel of other more common CYP isozymes. (c) 2005 Elsevier Ltd. All rights reserved.