We have synthesized two potential positron emission tomography (PET) radioligands for the endothelin (ET) receptor. [11C]-PD156707 was produced by O-methylation of PD169390 using [11C]iodomethane. Radiochemical conversions of the order of 74 ± 3.2% (n = 8) were obtained. The radiochemical purity of the isolated [11C]-PD156707 was 99% and the specific activity was 538 mCi/μmol. [18F]-BQ3020 was produced from [18F]fluoride in a total radiochemical yield of 2.7 ± 0.4% (n = 10) in 238 ± 5 min. The radiochemical purity was 95% and specific activities of the order of 670-930 mCi/μmol were obtained.
Clinical Pharmacology Unit and *Wolfson Brain Imaging Centre, University of Cambridge, Addenbrooke's Hospital, Cambridge, U.K.
Address correspondence and reprint requests to Peter Johnström, Clinical Pharmacology Unit, Centre for Clinical Investigation, Box 110, Addenbrooke's Hospital, Hills Road, Cambridge CB2 2QQ, U.K. E-mail: [email protected]; http://www-davenport. medschl.cam.ac.uk/
© 2000 Lippincott Williams & Wilkins, Inc.