Synthesis of the labeled D1 receptor antagonist SCH 23390 using [11C]carbon dioxide.
A new synthesis is described for the production of the positron emitting radiopharmaceutical R-(+)-7-chloro-8-hydroxy-2,3,4,5-tetrahydro-3-N-[11C]methyl-1-phenyl-1H- 3-benzazepine (SCH 23390, 2a). This novel method involves reductive carboxylation, in which [11C]CO2 is reacted with the trimethylsilyl derivative of the desmethyl compound (SCH 24518, 1a) followed by treatment with lithium aluminum hydride, to afford no carrier added 11C-labeled SCH 23390. The procedure gave chemically and radiochemically pure 11C-labeled SCH 23390 in 53-72% radiochemical yield with an unoptimized specific activity of 40 Ci/mmol within 45-50 min from the end of bombardment.
Ram
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Department of Radiology, Duke University Medical Center, Durham, NC 27710.
Ehrenkaufer
R E
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Spicer
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LD
D001552:Benzazepines / Q000138:chemical synthesis*; D002245:Carbon Dioxide; D002250:Carbon Radioisotopes; D018492:Dopamine Antagonists; D007553:Isotope Labeling
D001552:Benzazepines; D002250:Carbon Radioisotopes; D018492:Dopamine Antagonists; D002245:Carbon Dioxide