title: High reactivity of [11C]CH3I with thiol group in the synthesis of C-11 labeled radiopharmaceuticals.
abstract: High reactivity of [11C]-methyl iodide ([11C]CH3I) with the thiol group was demonstrated with cysteamine and other compounds containing a thiol and another functional groups in each structure. The methylation of the thiol group in cysteamine with [11C]CH3I was very rapid at 0 degree C with no catalyst, and gave a high radiochemical yield and purity without any detectable by-product. Moreover, this reaction was not disturbed by the other functional groups, such as -NH2, -OH and -COOH in the same structure. This S-methylation reaction is very useful for producing a new radiopharmaceutical labeled with the short lived positron emitting nuclide C-11.
authors.affiliation: Department of Nuclear Medicine, Faculty of Medicine, Kyoto University, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Magata
authors.forename: H
authors.initials: H
authors.lastname: Saji
authors.forename: T
authors.initials: T
authors.lastname: Tokui
authors.forename: Y
authors.initials: Y
authors.lastname: Ohmomo
authors.forename: Y
authors.initials: Y
authors.lastname: Yamada
authors.forename: M
authors.initials: M
authors.lastname: Hirata
authors.forename: J
authors.initials: J
authors.lastname: Konishi
authors.forename: A
authors.initials: A
authors.lastname: Yokoyama
mesh_terms: D002250:Carbon Radioisotopes; D006847:Hydrocarbons, Iodinated / Q000737:chemistry*; D007553:Isotope Labeling; D013438:Sulfhydryl Compounds / Q000737:chemistry*
chemical_list: D002250:Carbon Radioisotopes; D006847:Hydrocarbons, Iodinated; D013438:Sulfhydryl Compounds; C014055:methyl iodide