Evaluation and improvement of CuI ‐mediated 11C‐cyanation

CuI-mediated11C-cyanation was evaluated by synthesizing [11C]perampanel and compared with previous works. In vivo evaluations of [11C]perampanel using PET imaging were performed, and it showed the rapid spreading of [11C]perampanel into the brain, heart, and lung and its accumulation in the small intestine. In addition, the reaction conditions for CuI-mediated11C-cyanation of small molecules were optimized by using K2CO3 or prolonging the reaction time, and the RCY of11C-cyanation was improved. This improved method was applied to various (hetero)aromatic bromides. CuI-mediated11C-cyanation was evaluated by synthesizing [11C]perampanel ([11C]5) as a model compound and compared with previous reports. To a DMF solution with 5 ′-(2-bromophenyl)-1′-phenyl-[2,3′-bipyridin]-6′(1′H)-one (4) and CuI, [11C]NH4CN in a stream of ammonia/nitrogen (5:95, v/v) gas was bubbled. Subsequently, the reaction mixture was heated at 180 °C for 5 min. After HPLC purification, [11C]5 was obtained in 7.2  ± 1.0% (n = 4) non-decay corrected radiochemical yield with>99% radiochemical purity and a molar activity of 98  ± 28 GBq/μmol. In vivo evaluations of [11C]5 were performed using small animals. PET scans to check the kinetics of [11C]5 in the whole body of mice suggested that [11C]5 spreads rapidly into the brain, heart, and lungs and then accumulates in the small intestine. To evaluate the performance of CuI-mediated11C-cyanation reaction, bromobenzene (6a) was select...
Source: Journal of Labelled Compounds and Radiopharmaceuticals - Category: Biochemistry Authors: Tags: RESEARCH ARTICLE Source Type: research