18F-labelling of a potent nonpeptide CCR1 antagonist: synthesis of 1-(5-chloro-2-{2-[(2R)-4-(4-[18F]fluorobenzyl)-2-methylpiperazin-1-yl]-2-oxoethoxy}phenyl)urea in an automated module

✍ Scribed by P. Mäding; F. Füchtner; B. Johannsen; J. Steinbach; C. S. Hilger; M. Friebe; M. Halks-Miller; R. Horuk; R. Mohan

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: French
• Weight: 195 KB
• Volume: 49
• Category: Article
• ISSN: 0022-2135
• DOI: 10.1002/jlcr.1023

✦ Synopsis

Abstract

The synthesis of 1‐(5‐chloro‐2‐{2‐[(2R)‐4‐(4‐[^18^F]fluorobenzyl)‐2‐methylpiperazin‐1‐yl]‐2‐oxoethoxy}phenyl)urea ([^18^F]4), a potent nonpeptide CCR1 antagonist, is described as a module‐assisted two‐step one‐pot procedure. The final product was obtained utilizing the reductive amination of the formed 4‐[^18^F]fluorobenzaldehyde (2) with a piperazine derivative 3 and sodium cyanoborohydride. After HPLC purification of the final product [^18^F]4, its solid phase extraction, formulation and sterile filtration, the isolated (not decay‐corrected) radiochemical yields of [^18^F]4 were between 7 and 13% (n=28). The time of the entire manufacturing process did not exceed 95 min. The radiochemical purity of [^18^F]4 was higher than 95%, the chemical purity ⩾60% and the enantiomeric purity >99.5%. The specific radioactivity was in the range of 59–226 GBq/µmol at starting radioactivities of 23.6–65.0 GBq [^18^F]fluoride. Copyright © 2006 John Wiley & Sons, Ltd.