Synthesis and biological evaluation of ferrocene-based cannabinoid receptor 2 ligands

Ferrocene analogues of known fatty acid amide hydrolase inhibitors and CB2 ligands have been synthesized and characterized spectroscopically and crystallographically. The resulting bioorganometallic isoxazoles were assayed for their effects on CB1 and CB2 receptors as well as on FAAH. None had any FAAH activity but compound 3, 5-(2-(pentyloxy)phenyl)-N-ferrocenylisoxazole- 3-carboxamide, was found to be a potent CB2 ligand (Ki = 32.5 nM).