BOPTA is a derivative of
DTPA in which one terminal
carboxyl group, –C(O)OH is replaced by -C–O–CH2C6H5. Thus gadobenic acid is closely related to
gadopentetic acid. BOPTA itself was first synthesized in 1995.[5] In the "gadobenate" ion gadolinium ion is 9-
coordinate with BOPTA acting as an 8-coordinating ligand. The ninth position is occupied by a water molecule, which exchanges rapidly with water molecules in the immediate vicinity of the strongly
paramagnetic complex, providing a mechanism for
MRI contrast enhancement. 139La NMR studies on the diamagnetic La-BOPTA2− complex suggest that the Gd complex maintains in solution the same kind of
coordination as found, by
X-ray crystallography, in the
solid state for Gd-BOPTA disodium salt.[5]
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abUggeri F, Aime S, Anelli PL, Botta M, Brocchetta M, de Haeen C, Ermondi G, Grandi M, Paoli P (1995). "Novel Contrast Agents for Magnetic Resonance Imaging. Synthesis and Characterization of the Ligand BOPTA and Its Ln(III) Complexes (Ln = Gd, La, Lu). X-ray Structure of Disodium (TPS-9-145337286-C-S)-[4-Carboxy-5,8,11-tris(carboxymethyl)-1-phenyl-2-oxa- 5,8,11-triazatridecan-13-oato(5-)]gadolinate(2-) in a Mixture with Its Enantiomer". Inorganic Chemistry. 34 (3): 633–643.
doi:
10.1021/ic00107a017.
ISSN0020-1669.