title: A new high-yield synthetic route to PET CB1 radioligands [11C]OMAR and its analogs.
abstract: OMAR analogs reference standards and their corresponding desmethylated precursors were synthesized from substituted anilines either in 4 and 5 steps with 27-32% and 24-31% yield, or in 3 and 4 steps with 21-30% and 19-28% yield, respectively. [(11)C]OMAR and its analog radioligands were prepared from their desmethylated precursors with [(11)C]CH(3)OTf through O-[(11)C]methylation and isolated by HPLC combined with solid-phase extraction (SPE) in 50-65% radiochemical yields based on [(11)C]CO(2) and decay corrected to end of bombardment (EOB), with 370-740 GBq/μmol specific activity at EOB.
authors.affiliation: Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
authors.forename: Mingzhang
authors.initials: M
authors.lastname: Gao
authors.forename: Min
authors.initials: M
authors.lastname: Wang
authors.forename: Qi-Huang
authors.initials: QH
authors.lastname: Zheng
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry; D000818:Animals; D001921:Brain / Q000000981:diagnostic imaging; D002250:Carbon Radioisotopes / Q000737:chemistry; D006801:Humans; D007553:Isotope Labeling; D008024:Ligands; D010880:Piperidines / Q000138:chemical synthesis / Q000737:chemistry*; D049268:Positron-Emission Tomography; D011720:Pyrazoles / Q000138:chemical synthesis / Q000737:chemistry*; D019275:Radiopharmaceuticals / Q000138:chemical synthesis* / Q000737:chemistry; D043884:Receptor, Cannabinoid, CB1 / Q000037:antagonists & inhibitors* / Q000378:metabolism; D013329:Structure-Activity Relationship
chemical_list: C515663:4-cyano-1-(2,4-dichlorophenyl)-5-(4-methoxyphenyl)-N-(piperidin-1-yl)-1H-pyrazole-3-carboxamide; D000814:Aniline Compounds; D002250:Carbon Radioisotopes; D008024:Ligands; D010880:Piperidines; D011720:Pyrazoles; D019275:Radiopharmaceuticals; D043884:Receptor, Cannabinoid, CB1; C023650:aniline