title: Insight into technetium amidoxime complex: oxo technetium(V) complex of N-substituted benzamidoxime as new basic structure for molecular imaging.
abstract: In search of benzamidoxime (BHam) derivatives that provide a single (99m)Tc-labeled compound of high in vivo stability, we synthesized three N-alkyl compounds of benzamidoxime (BHam) ligand. They provided a single (99m)Tc-labeled compound by ligand exchange reaction of (99m)Tc-glucoheptonate in high radiochemical yields (over 95% at MBHam concentration of 1 × 10(-5) M). (99m)Tc-N-methyl benzamidoxime ((99m)Tc-MBHam) showed higher stability than the parental (99m)Tc-BHam. The complex of this compound with (99g)TcO(3+) ion was prepared, isolated, and characterized by FT-IR and NMR spectra as well as X-ray diffraction. (99g)Tc-MBHam crystallized in an orthorhombic space group Pna2(1) with a = 13.4823(5), b = 15.5410(7), c = 7.7907(3) Å, V = 1632.39(11) Å(3), and Z = 4. The (99g)Tc complex possessed square base pyramid coordination geometry. The equatorial plane was formed by two-amine nitrogen and two-oxime oxygen atoms in trans position, while the oxo core of the technetium(V) occupied the apical position. The (99g)Tc-MBHam proved to be identical with the (99m)Tc-MBHam prepared at the no-carrier-added level by comparison of their HPLC profiles.
authors.affiliation: Department of Chemistry, Faculty of Science, Burapha University, Chonburi, Thailand.
authors.forename: Khajadpai
authors.initials: K
authors.lastname: Thipyapong
authors.forename: Tomoya
authors.initials: T
authors.lastname: Uehara
authors.forename: Yuji
authors.initials: Y
authors.lastname: Tooyama
authors.forename: Henrik
authors.initials: H
authors.lastname: Braband
authors.forename: Roger
authors.initials: R
authors.lastname: Alberto
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Arano
mesh_terms: D001550:Benzamidines / Q000737:chemistry*; D018360:Crystallography, X-Ray; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D019275:Radiopharmaceuticals / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D017556:Technetium Compounds / Q000737:chemistry*
chemical_list: D001550:Benzamidines; D019275:Radiopharmaceuticals; D017556:Technetium Compounds; C053561:benzamidoxime