Analogues of doxanthrine reveal differences between the dopamine D1 receptor binding properties of chromanoisoquinolines and hexahydrobenzo[a]phenanthridines
作者:Juan Pablo Cueva、Benjamin R. Chemel、Jose I. Juncosa、Markus A. Lill、Val J. Watts、David E. Nichols
DOI:10.1016/j.ejmech.2011.11.039
日期:2012.2
Efforts to develop selective agonists for dopamine D-1-like receptors led to the discovery of dihydrexidine and doxanthrine, two bioisosteric [beta-phenyldopamine-type full agonist ligands that display selectivity and potency at D-1-like receptors. We report herein an improved methodology for the synthesis of substituted chromanoisoquinolines (doxanthrine derivatives) and the evaluation of several new compounds for their ability to bind to D-1- and D-2-like receptors. Identical pendant phenyl ring substitutions on the dihydrexidine and doxanthrine templates surprisingly led to different effects on D-1-like receptor binding, suggesting important differences between the interactions of these ligands with the D-1 receptor. We propose, based on the biological results and molecular modeling studies, that slight conformational differences between the tetralin and chroman-based compounds lead to a shift in the location of the pendant ring substituents within the receptor. (C) 2011 Elsevier Masson SAS. All rights reserved.