Improved procedures for the radiosynthesis of α‐[11C]methyltryptophan and α‐[11C]methyl‐tryptophan methyl ester were studied. Following α‐deprotonation of tryptophan methyl ester benzaldimine with LDA, 60 – 80% of no carrier added [11C]iodomethane was incorporated in 5 minutes at 27 – 30°C. After HPLC purification, radiochemically pure α‐[11C]methyl‐tryptophan or its methyl ester was produced with minimum chemical contamination from tryptophan. The [11C]methyl‐tryptophan synthesized, however, was found to be a racemate.
ASJC Scopus subject areas
- Analytical Chemistry
- Radiology Nuclear Medicine and imaging
- Drug Discovery
- Organic Chemistry