The primary goal of this proposal is to design and synthesize novel 2-arachidonoylglycerol analogs (2-AG) with improved potency and biochemical stability as pharmacological probes for key endocannabinoid targets. The most successful of the resulting new ligands will contribute our understanding of the role of 2- arachidonoylglycerol (2-AG) in endocannabinoid signaling and its influence on appetite, substance abuse, and other (patho)physiological processes. The first objective involves synthesis of metabolically stable analog of 2- AG, as endogenous 2-AG undergoes spontaneous enzymatic degradation and acyl migration. The proposed structural features include: (a) increasing stability of ester by introducing (i) steric hindrance and (ii) bioisosteres and (b) modifying chain to mimic lipophilic chain of arachidonic acid (including various substituted phenyl, biphenyls, diphenylmethane and oxydibenzene) (c) The second objective is to develop a covalent probe exploring the ligand binding motifs involved in the activation of the cannabinoid receptors (CB1 and CB2) by their endogenous ligand, 2-AG. These newly synthesized 2-AG analogs will be assayed for their affinity to the cannabinoid receptors CB1 and CB2 as well as inhibition of endocannabinoid proteins: monoacylglycerol lipase (MAGL), fatty acid amide hydrolase (FAAH), the putative endocannabinoid transporter system. The lack of stable 2-AG analogs represents a significant void in the research tools available to dissect the endocannabinoid system and study its delicate balance with lipid metabolism, calcium ion transport, inflammation, cell signaling, and reward mechanisms in the brain. The downregulation of the endocannabinoid system is particularly important for medical conditions related to overstimulation of the cannabinoid receptor including recovery from substance abuse, obesity, and movement disorders. PUBLIC HEALTH RELEVANCE: The endocannabinoid system is involved in cell signaling which affect pain, hunger, and cravings for drugs of abuse. A number of currently popular medications antagonize the endocannabinoid receptor proteins and the goal of this proposal is to design and synthesize novel 2-arachidonoylglycerol analogs (2-AG) with improved potency and biochemical stability as pharmacological probes for key endocannabinoid targets. The most successful of the resulting new ligands will contribute our understanding of the role of 2-arachidonoylglycerol (2-AG) in endocannabinoid signaling and its influence on appetite, substance abuse, and other (patho)physiological processes.