Ligand Design for Alpha1 Adrenoceptors

An area of continuing interest in medicinal chemistry is the design, synthesis and pharmacological evaluation of ligands which bind at adrenoceptor subtypes, which include alpha 1A , alpha 1B ,alpha 1D ; alpha 2A , alpha 2B , alpha 2C beeta 1 , beeta 2 , beeta 3 and possibly beeta 4 subtypes. The selective blockade or stimulation of these receptor subtypes is of on-going pharmacological and medicinal interest. However, the design principles for ligand differentiation at these subtypes still need further development. This review focuses on alpha 1 adrenoceptors with a concentration on literature over the past five years. Structural, physiological and therapeu-tic aspects of the alpha 1A , alpha 1B and alpha 1D subtypes are discussed together with ligands binding to these receptor subtypes. Approaches to alpha 1 adrenoceptor ligand design based on known ligands and on receptor docking are evaluated. A new combined approach using pharmacophores and receptor docking affords possibilities for deeper insights into achieving small molecule binding selectivity.