Synthesis of 3,4-dihydro-5-[11C]methoxy-1(2H)-isoquinolinone as a Potential Tracer for Poly(ADP-ribose) Synthetase

Article abstract of DOI:10.1002/1099-1344(200009)43:10<983::AID-JLCR383>3.0.CO;2-C

Synthesis of 3,4-dihydro-5-[11C]methoxy-1(2H)-isoquinolinone ([11C]MIQO), a potent poly (ADP-ribose) synthetase inhibitor, was devised in order to evaluate whether it is possible to image excessive activation of poly(ADP-ribose) synthetase (PARS) by positron emission tomography. [11C]MIQO was prepared by O-[11C]methylation of 3,4-dihydro-5-hydroxy-1(2H)-isoquinolinone, obtained by a Schmidt reaction with 4-hydroxy-1-indanone, sodium azide and trichloroacetic acid, with [11C]methyl triflate. Total synthesis time from EOB was 35 minutes. The radiochemical yield based on [11C]carbon dioxide was 31 +/- 8 percent (n=8; decay corrected). The final product had a specific activity of 76 GBq/umol at EOS, and the radiochemical purity of [11C]MIQO was over 99 percent.