Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8208869 | Applied Radiation and Isotopes | 2018 | 7 Pages |
Abstract
The reference standard N-(3-(4-methylpiperazin-1-yl)â1-(5-methylpyridin-2-yl)â1H-pyrazol-5-yl)pyrazolo[1,5-a]pyrimidine-3-carboxamide (9) and its demethylated precursor N-(1-(5-methylpyridin-2-yl)â3-(piperazin-1-yl)â1H-pyrazol-5-yl)pyrazolo[1,5-α]pyrimidine-3-carboxamide (8) were synthesized from pyrazolo[1,5-a]pyrimidine-3-carboxylic acid and ethyl 2-cyanoacetate with overall chemical yield 13% in nine steps and 14% in eight steps, respectively. The target tracer N-(3-(4-[11C]methylpiperazin-1-yl)â1-(5-methylpyridin-2-yl)â1H-pyrazol-5-yl)pyrazolo[1,5-a]pyrimidine-3-carboxamide ([11C]9) was prepared from its precursor with [11C]CH3OTf through N-[11C]methylation and isolated by HPLC combined with SPE in 50-60% radiochemical yield, based on [11C]CO2 and decay corrected to EOB. The radiochemical purity was >99%, and the specific activity at EOB was 370-1110 GBq/μmol.
Related Topics
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Authors
Xiaohong Wang, Wenzhi Xu, Caihong Miao, Fugui Dong, Wei Li, Min Wang, Mingzhang Gao, Qi-Huang Zheng, Zhidong Xu,