Some new DTPA-N,N″-bis(amides) functionalized by alkyl carboxylates: Synthesis, complexation and stability properties

Gd-Complexes of 1,4,7,10-Tetraazacyclododecane-N,N′,N′′,N′′′-1,4,7,10-tetraacetic Acid (DOTA) Conjugates of Tranexamates as a New Class of Blood-Pool Magnetic Resonance Imaging Contrast Agents

“…In this connection, it has already been pointed out that the presence of the tranexamic moiety helps to enhance R 1 -relaxivity of 6 mostly through an increase in the rotational correlation time (τ R ) compared with simple DTPA-BMA. [13][14][15] Relaxivity. Figure 2 shows the relaxation time (T 1 ) and relaxivity (R 1 ) maps on 5a-c and Gd-DOTA.…”

Gd-Complexes of New Arylpiperazinyl Conjugates of DTPA-Bis(amides): Synthesis, Characterization and Magnetic Relaxation Properties

“…The development of an optimum MRI contrast agent would necessitate consideration of the high relaxivity, non-cytotoxicity and high water solubility of the targeted complexes. As suggested by earlier reports, modification of the ligand, for instance by the introduction of polar groups on the alkyl substituents of the amide N-atoms of DTPA-bis(amide), can lead to the formation of water soluble Gd-complexes [16]. Therefore, we intended to synthesize Gd-complexes with different arylpiperazine ligands bearing different functionalities in the aryl moiety.…”

Lanthanide complexes with polyaminopolycarboxylates as prospective NMR/MRI diagnostic probes: peculiarities of molecular structure, dynamics and paramagnetic properties

“…Other example of the selectivity of DTPA-bis(amide) ligands for the Gd(III) ion over the endogenous metal ions such as Zn(II), Ca(II), and Cu(II), and relaxivities (r 1 and r 2 ) of Gd(III)-DTPA-bis(amide) complexes both in aqueous and hydroxypropyl-b-cyclodextrin (HP-b-CD) solutions reported by T. J. Kim [194]. HP-b-CD is biocompatible and has been used in the preparation of aqueous solution of water-insoluble drugs [195] It is known that a significant increase in relaxivity is established when ''host-guest'' inclusion complexes are formed between the hydrophobic b-cyclodextrin cavity Fig. 17 Structure of the DTPA ligand (A), ball-and-stick representation of a metal-DTPA complex (B).…”