Synthesis of a 11C-labelled taxane derivative by [1-11C]acetylation

The C-11-labelling of the taxane derivative BAY 59-8862 (1), a potent anticancer drug, was carried out as a module-assisted automated multi-step synthesis procedure. The radiotracer [C-11]1 was synthesized by reacting [1-C-11]acetyl chloride (6) with the lithium salt of the secondary hydroxy group of precursor 3 followed by deprotection. After HPLC purification of the final product [C-11]1, its solid-phase extraction, formulation and sterile filtration, the decay-corrected radiochemical yield of [C-11]1 was in the range between 12 and 23% (related to [C-11]CO2; n= 10). The total synthesis time was about 54 min after EOB. The radiochemical purity of [C-11]1 was greater than 96% and the chemical purity exceeded 80%. The specific radioactivity was 16.8 +/- 4.7 GBq/mu mol (n = 10) at EOS starting from 80 GBq Of [C-11]CO2, Copyright (c) 2006 John Wiley & Sons, Ltd.