UR-144, a synthetic cannabinoid, exhibits high affinity for the peripheral cannabinoid receptor (CB2) with a Ki of 1.8 nM, markedly greater than its affinity for the central cannabinoid receptor (CB1), for which it has a Ki of 150 nM. XLR-11 differs from UR-144 by featuring a fluorine atom on the terminal carbon of the alkyl chain and a methyl group on the C2 carbon of the indole. The specific biological activities of XLR-11 remain uncharacterized. It is designed for forensic and research use only.
2,3-Bis(3-indolylmethyl)indole exhibits concentration-dependent inhibition of RANKL-induced osteoclastogenesis, actin ring formation, and bone resorption.