Synthesis and radiosynthesis of a novel PET fluorobenzyl piperazine for melanoma tumour imaging; [18F]MEL054

2-{2-[4-(4-[18F]-Fluorobenzyl)piperazin-1-yl]-2-oxoethyl}isoindolin-1-one ([18F]MEL054), is a new potent indolinone-based melanin binder designed to target melanotic tumours. [18F]MEL054 was prepared by an automated two-step radiosynthesis, comprising of the preparation of 4-[18F]fluorobenzaldehyde from 4-formyl-N,N,N-trimethylanilinium triflate, followed by reductive alkylation with 2-(2-oxo-2-piperazin-1-ylethyl)isoindolin-1-one. 4-[18F]Fluorobenzaldehyde was prepared on a GE TRACERlab FXFN module in 68 ± 8 % radiochemical yield (RCY, non-decay corrected), purified by a Sep-Pak Plus C18 cartridge and eluted into the reactor of an in-house modified Nuclear Interface [18F]FDG synthesis module for the subsequent reductive alkylation reaction. HPLC purification produced [18F]MEL054 in a collected RCY of 34 ± 9 % (non-decay corrected), the total preparation time (including Sep-Pak Plus C18 and HPLC purification) did not exceed 105 min. The radiochemical purity of [18F]MEL054 was greater than 99 % with a specific radioactivity of 71–119 GBq μmol–1 and [18F]MEL054 remained stable in saline solution (>98 %) after 3 h. © 2013 CSIRO.

Keywords

Fluorine 18, Radiochemistry, Piperazines, High-performance liquid chromatography, Melanin, Neoplasms, Alkylation

Citation

Taylor, S. R., Roberts, M. P., Wyatt, N. A., Pham, T. Q., Stark, D., Bourdier, T., Roselt, P., Katsifis, A., & Greguric, I. (2013). Synthesis and radiosynthesis of a novel PET Fluorobenzyl piperazine for melanoma tumour imaging; [18F] MEL054. Australian Journal of Chemistry, 66(4), 491-499. doi:10.1071/CH12489