Treatment of 2-vinylbenzamide derivatives with sulfinate sodium in the presence of Cu­(NO3)2·3H2O led to an intra/intermolecular aminosulfonylation reaction to produce sulfonylated lactams in moderate to good yields. The developed method features the easily available and stable sulfone reagents, ease of operation, and a broad functional group tolerance.

To develop PET tracers for imaging of Alzheimer's disease, new carbon-11 labeled potent and selective PDE5 inhibitors have been synthesized. The reference standards (5) and (12), and their corresponding desmethylated precursors (6) and (13) were synthesized from methyl 2-amino-5bromobenzoate and (4-methoxyphenyl)methanamine in multiple steps with 2%, 1%, 1% and 0.2% overall chemical yield, respectively. The radiotracers ([ 11 C]5) and ([ 11 C]12) were prepared from their corresponding precursors 6 and 13 with [ 11 C]CH3OTf through O-11 C-methylation and isolated by HPLC combined with SPE in 40-50% radiochemical yield, based on [ 11 C]CO2 and decay corrected to EOB. The radiochemical purity was >99%, and the molar activity (Am) at EOB was in a range of 370-740 GBq/µmol.

No abstract

Carbon-11-labeled serotonin (5-hydroxytryptamine) 6 receptor (5-HT 6 R) antagonists, 1-[(2-bromophenyl)sulfonyl]-5-[ 11 C]methoxy-3-[(4-methyl-1-piperazinyl)methyl]-1H-indole (O-[ 11 C]2a) and 1-[(2-bromophenyl)sulfonyl]-5-methoxy-3-[(4-[ 11 C]methyl-1-piperazinyl)methyl]-1H-indole (N-[ 11 C]2a), 5-[ 11 C]methoxy-3-((4-methylpiperazin-1-yl)methyl)-1-(phenylsulfonyl)-1Hindole (O-[ 11 C]2b) and 5-methoxy-3-((4-[ 11 C]methylpiperazin-1-yl)methyl)-1-(phenylsulfonyl)-1H-indole (N-[ 11 C]2b), 1-((4isopropylphenyl)sulfonyl)-5-[ 11 C]methoxy-3-((4-methylpiperazin-1-yl)methyl)-1H-indole (O-[ 11 C]2c) and 1-((4isopropylphenyl)sulfonyl)-5-methoxy-3-((4-[ 11 C]methylpiperazin-1-yl)methyl)-1H-indole (N-[ 11 C]2c), 1-((4-fluorophenyl)sulfonyl)-5-[ 11 C]methoxy-3-((4-methylpiperazin-1-yl)methyl)-1H-indole (O-[ 11 C]2d) and 1-((4-fluorophenyl)sulfonyl)-5-methoxy-3-((4-[ 11 C]methylpiperazin-1-yl)methyl)-1H-indole (N-[ 11 C]2d), were prepared from their O-or N-desmethylated precursors with [ 11 C]CH 3 OTf through O-or N-[ 11 C]methylation and isolated by HPLC combined with SPE in 40-50% radiochemical yield, based on [ 11 C]CO 2 and decay corrected to end of bombardment (EOB). The radiochemical purity was >99%, and the molar activity (MA) at EOB was 370-740 GBq/µmol with a total synthesis time of ~40-minutes from EOB.

The reference standard N-(3-(4-methylpiperazin-1-yl)-1-(5-methylpyridin-2-yl)-1H-pyrazol-5-yl)pyrazolo[1,5-a]pyrimidine-3-carboxamide (9) and its demethylated precursor N-(1-(5-methylpyridin-2-yl)-3-(piperazin-1-yl)-1H-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-[C]methylpiperazin-1-yl)-1-(5-methylpyridin-2-yl)-1H-pyrazol-5-yl)pyrazolo[1,5-a]pyrimidine-3-carboxamide ([C]9) was prepared from its precursor with [C]CHOTf through N-[C]methylation and isolated by HPLC combined with SPE in 50-60% radiochemical yield, based on [C]CO and decay corrected to EOB. The radiochemical purity was >99%, and the specific activity at EOB was 370-1110 GBq/μmol.