1350523-19-1Relevant articles and documents
Facile aromatic radiofluorination of [18F]flumazenil from diaryliodonium salts with evaluation of their stability and selectivity
Moon, Byung Seok,Kil, Hee Seup,Park, Jun Hyung,Kim, Ji Sun,Park, Jimin,Chi, Dae Yoon,Lee, Byung Chul,Kim, Sang Eun
experimental part, p. 8346 - 8355 (2012/05/04)
Aromatic radiofluorination of the diaryliodonium tosylate precursor with [18F]fluoride ions has been applied successfully to access [ 18F]flumazenil in high radiochemical yields of 67.2 ± 2.7% (decay corrected). The stability and reactivity of the diaryliodonium tosylate precursor plays a key role in increasing the production of 18F- labelled molecules under the fluorine-18 labelling condition. Various conditions were explored for the preparation of [18F]flumazenil from different diaryliodonium tosylate precursors. Optimum incorporation of [ 18F]fluoride ions in the 4-methylphenyl-mazenil iodonium tosylate precursor (5f) was achieved at 150°C for 5 min by utilizing 4 mg of the precursor, K2.2.2/K2CO3 complex, and the radical scavenger in N,N-dimethylformamide. This approach was extended to a viable method for use in automated synthesis with a radiochemical yield of 63.5 ± 3.2% (decay corrected, n = 26) within 60.0 ± 1.1 min. [ 18F]Flumazenil was isolated by preparative HPLC after the reaction was conducted under improved conditions and exhibited sufficient specific activity of 370-450 GBq μmol-1, with a radiochemical purity of >99%, which will be suitable for human PET studies. The Royal Society of Chemistry 2011.