Abstract
Alpha-[ 11C]methyl- l-tryptophan (AMT) has been synthesized by stereoselective methylation with [ 11C]methyl iodide of the lithium-enolate generated by treating dimethyl 2(S),3a(R),8a(S)-(+)-hexahydro-8(phenylsulfonyl) pyrrolo[2,3-b]indole-1,2-dicarboxylate (2) with lithium diisopropyl amide (LDA) at −55 °C, followed by ring opening using trifluoroacetic acid and alkaline hydrolysis of the protecting groups. The crude product was purified by a simple reverse-phase C-18 Sep-Pak procedure. The purified product was isolated with an average radiochemical yield of 53 ± 12% (decay corrected) in 30–35 min from [ 11C]methyl iodide. At end of synthesis (EOS), 138 ± 35 mCi ( n = 24) of product was collected with a specific activity of ca. 1–1.3 Ci/μmol (EOS) (4–5 Ci/μmol @ EOB) starting from 1.5 Ci (EOB) of [ 11C]CO 2.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
