Synthesis of 2‐{(4‐chlorophenyl) (4‐ 125 Iiodophenyl)} methoxyethyl‐1‐piperidine‐3‐carboxylic acid, 125 ICIPCA: A potential radiotracer for GABA uptake sites

摘要

The synthesis of racemic [2‐{(4‐Chlorophenyl) (4‐iodophenyl)} methoxyethyl]‐1‐piperidine‐3‐carboxylic acid, (CIPCA) and its radioiodinated analog [ 125ß I]CIPCA is described. CIPCA was synthesized from 4‐iodobenzoyl chloride in five steps in 16% overall yield. Ammonium sulfate catalyzed solid‐state isotopic exchange of CIPCA with Na 125 I provided [ 125 I]CIPCA in 34% isolated radiochemical yield at a specific activity of 118 Ci/mmol. [ 125 ICIPCA] demonstrated moderate brain extraction and good in vivo radiostability in preliminary biodistribution studies conducted in CD‐1 mice. [ 125 I]CIPCA is a potentially useful radiotracer for study of the GABA uptake system.