2-Arachidonoylglycerol (2-AG) is identified as a more potent endogenous cannabinoid ligand compared to its analogue, 1-Arachidonoylglycerol (1-AG), exhibiting 10 to 100 times the ligand binding affinity and agonist activity at the CB1 receptor, thus making it a natural ligand. However, 2-AG's chemical instability leads to rapid isomerization to 1-AG (also referred to as 1(3)-AG) both in vitro and in vivo. This isomerization process, where 1-AG becomes a frequent contaminant in synthetic 1-AG preparations, significantly decreases their cannabinergic potency. Furthermore, 1-AG is characterized as a weak CB1 receptor agonist with potential for other pharmacological effects.