Investigation of SN2 [11C]cyanation for base-sensitive substrates: an improved radiosynthesis of L-[5-11C]-glutamine.
Amino Acids
; 47(3): 525-33, 2015 Mar.
Article
em En
| MEDLINE
| ID: mdl-25488428
ABSTRACT
Carbon-11 (ß(+) emitter, t1/2 = 20.4 min) radiolabeled L-glutamine is a potentially useful molecular imaging agent that can be utilized with positron emission tomography for both human oncological diagnosis and plant imaging research. Based upon a previously reported [(11)C]cyanide end-capping labeling method, a systematic investigation of nucleophilic cyanation reactions and acidic hydrolysis reaction parameters, including base, metal ion source, phase transfer catalyst, solvent, reaction temperature and reaction time, was conducted. The result was a milder, more reliable, two-step method which provides L-[5-(11)C]-glutamine with a radiochemical yield of 63.8 ± 8.7% (range from 51 to 74%, n = 10) with >90% radiochemical purity and >90 % enantiomeric purity. The total synthesis time was 40-50 min from the end of bombardment. In addition, an Fmoc derivatization method was developed to measure the specific activity of this radiotracer.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Glutamina
/
Marcação por Isótopo
Tipo de estudo:
Diagnostic_studies
Limite:
Humans
Idioma:
En
Ano de publicação:
2015
Tipo de documento:
Article