Recent developments in cannabinoid ligands

Over the past 40 years, much research has been carried out directed toward the characterization of the cannabinergic system. With the identification of two G-protein coupled receptors and the endogenous ligand, anandamide, pharmacological targets have expanded to encompass hydrolase and transport proteins as well as novel classes of cannabinoid ligands. Those ligands that demonstrate high affinity for the receptors and good biological efficacy are tied together through lipophilic regions repeatedly demonstrated necessary for activity. This review presents recent developments in the structure-activity relationships of several classes of cannabinoid ligands.