title: Synthesis of DTPA analogues derived from piperidine and azepane: potential contrast enhancement agents for magnetic resonance imaging.
abstract: Two DTPA derivatives (PIP-DTPA and AZEP-DTPA) as potential contrast enhancement agents in MRI are synthesized. The T1 and T2 relaxivities of their corresponding Gd(III) complexes are reported. At clinically relevant field strengths, the relaxivities of the complexes are comparable to that of the contrast agent, Gd(DTPA) which is in clinical use. The serum stability of the (153)Gd-labeled complexes is assessed by measuring the release of (153)Gd from the ligands. The radiolabeled Gd chelates are found to be kinetically stable in human serum for up to at least 14 days without any measurable loss of radioactivity.
authors.affiliation: Chemistry Section, National Cancer Institute, NIH, Bethesda, Maryland, USA.
authors.forename: H S
authors.initials: HS
authors.lastname: Chong
authors.forename: K
authors.initials: K
authors.lastname: Garmestani
authors.forename: L H
authors.initials: LH
authors.lastname: Bryant
authors.forename: M W
authors.initials: MW
authors.lastname: Brechbiel
mesh_terms: D003287:Contrast Media / Q000737:chemistry*; D005682:Gadolinium / Q000097:blood / Q000737:chemistry; D019786:Gadolinium DTPA / Q000097:blood / Q000737:chemistry; D006571:Heterocyclic Compounds / Q000097:blood / Q000737:chemistry*; D008279:Magnetic Resonance Imaging / Q000379:methods; D019906:Nuclear Magnetic Resonance, Biomolecular; D004369:Pentetic Acid / Q000031:analogs & derivatives* / Q000097:blood / Q000737:chemistry*; D010880:Piperidines / Q000097:blood / Q000737:chemistry*; D011868:Radioisotopes / Q000097:blood / Q000737:chemistry
chemical_list: D003287:Contrast Media; D006571:Heterocyclic Compounds; D010880:Piperidines; D011868:Radioisotopes; C032727:piperidine; D004369:Pentetic Acid; D005682:Gadolinium; D019786:Gadolinium DTPA