title: Radiosynthesis of 1-[18F]fluoroethyl-L-tryptophan as a novel potential amino acid PET tracer.
abstract: (18)F labeled natural amino acids have been introduced as promising tumor imaging agents. A novel [(18)F]fluoro amino acid analog 1-[(18)F]fluoroethyl-L-tryptophan (1-[(18)F]FETrp) was designed and synthesized by a two-pot three-step procedure, including the synthesis of 1-[(18)F]fluoro-2- (tosyloxy)ethane, the [(18)F]fluoroethylation of the precursor N-Boc-L-tryptophan ethyl ester and following the deprotection of the tert-butoxycarbonyl and ethyl ester protecting groups. 1-[(18)F]FETrp was resulted in 0.9 ± 0.2% (n=5) radiochemical yields (no decay corrected) by HPLC purification, within a total synthesis time of 65 min. The radiochemical purity of 1-[(18)F]FETrp was 95-97%. The radiosynthetic method needs to be further optimized to get a satisfying radiochemical yield.
authors.affiliation: Department of Cardiac Function, Shanghai Ninth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200011, PR China. beibeisun2008@163.com
authors.forename: Ting
authors.initials: T
authors.lastname: Sun
authors.forename: Ganghua
authors.initials: G
authors.lastname: Tang
authors.forename: Hua
authors.initials: H
authors.lastname: Tian
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Wang
authors.forename: Xianghua
authors.initials: X
authors.lastname: Chen
authors.forename: Zhifeng
authors.initials: Z
authors.lastname: Chen
authors.forename: Shihchen
authors.initials: S
authors.lastname: Wang
mesh_terms: D000596:Amino Acids / Q000138:chemical synthesis; D002851:Chromatography, High Pressure Liquid; D005462:Fluorine Radioisotopes; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals / Q000138:chemical synthesis* / Q000302:isolation & purification; D014364:Tryptophan / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000302:isolation & purification
chemical_list: D000596:Amino Acids; D005462:Fluorine Radioisotopes; D019275:Radiopharmaceuticals; C025166:tryptophan ethyl ester; D014364:Tryptophan