Selective alkylation of pyrimidyl dianions III: no-carrier-added synthesis of [11C-methyl]-thymidine.
A no-carrier-added, high specific activity synthesis of [11C-methyl]-thymidine is reported. Reaction of 3'. 5'-O-bis-(tetrahydropyramyl)-5-bromo-2'-deoxyuridine with n-butylithium produced a diamion which was alkylated with [11C]-methyl iodide, and on subsequent hydrolysis, yielded [IIC-methyl]-thymidine. The labeled compound was isolated from the by-product 2'-deoxymidine by HPLC on a reverse phase C18 semipreparative column with mean radiochemical yield of 18.8% (decay corrected) in 30-35 min and radiochemical purity >99%. This no-carrier-added synthesis can be used to produce [11C-methyl]-thymidine with mean specific activity over 1000 mCi/mumol for positron emission tomography (PET) studies.
Alauddin
M M
MM
PET Imaging Science Center University of Southern California, School of Medicine Los Angeles, CA 90033, USA.
Ravert
H T
HT
Musachio
J L
JL
Mathews
W B
WB
Dannals
R F
RF
Conti
P S
PS
D000478:Alkylation; D000818:Animals; D002250:Carbon Radioisotopes; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D007202:Indicators and Reagents; D007553:Isotope Labeling / Q000379:methods; D009682:Magnetic Resonance Spectroscopy; D011743:Pyrimidines; D013936:Thymidine / Q000138:chemical synthesis*; D014055:Tomography, Emission-Computed
D002250:Carbon Radioisotopes; D007202:Indicators and Reagents; D011743:Pyrimidines; D013936:Thymidine