Potentiometric and spectroscopic studies of the cobalt(II), nickel(II) and manganese(II) complexes with some aminodiphosphonic acids in aqueous solution

Stoichiometry of lanthanide(iii) complexes with tripodal aminophosphonic ligands – a new solution to an old problem

“…27 Such a decrease of the highest protonation constant of H 4 NP 2 py is clearly caused by substitution of one of the phosphonic groups by the pyridine moiety. The same phenomenon has been noticed by Kurzak et al 28 in N-3-picolyliminodi(methylenephosphonic) acid (NP 3 py); the log K value of the tertiary amine was found to be 10.40(1) in 0.2 M KCl. The following deprotonation steps of H 4 NP 2 py release the protons from both phosphonic groups; log K 2 = 6.74(4), log K 4 = 2.23(5) and the pyridine moiety; log K 3 = 5.61(4) ( Table 4).…”

Highly stable acyclic bifunctional chelator for 64Cu PET imaging

“…These values as well as the corresponding protonation constants are gathered in Table 1. These stability constants of the metal complexes with L 1 are compared to those reported (Table 4) in the literature for models such as L A (the amino-N,N-bis(methanephosphonate) unit of L 1 ) [56-58, 72, 73], EDTPA (noted L B , the phosphonate analogue of EDTA) [74], L E [75], L H [76,77], L I [61,72,78], L J [78] or DO2P (1,4,7,10-tetraazacyclododecane-1,7-bis(methanephosphonate)). Importantly, ligand DO2P constitutes one of the most efficient phosphonate ligands for Cu(II) complexation described until now [43,44].…”

“…L 1 , DO2P, L B and L F (or EDTPA) lead to the more stable Cu(II) complexes and repBrought to you by | New York University Bobst Library Technical Services Authenticated Download Date | 5/31/15 4:34 AM Table 5. Calculated pM values (M = Cu(II), Zn(II), Ni(II), Co(II) and Ga(III)) for L 1 and aminomethanephosphonate or aminocarboxylate derivatives (Chart 2 [43,44] 17.77 b 17.77 b 11.73 11.73 nd nd nd nd nd nd L A [59] 8.75 9.20 6.50 9.0 6.21 7.15 6.08 9.0 nd nd L B [56][57][58] 14.10 14.10 11.67 11.67 10.45 10.46 9.57 9.68 nd nd L D [86] 6.30 9.0 nd nd 6.30 9.0 6.02 9.0 nd nd L E [75] 6.0 9.0 6.0 9.0 6.0 9.0 6.0 9.0 nd nd L F [41,42,56] 14.00 14.00 9.03 9.33 10.21 10.23 8.84 9.24 nd nd L G [48] 12.07 12.07 13.68 13.68 nd nd nd nd nd nd L H [59,77] 10.88 10.88 9.73 9.80 7.87 9.03 9.20 9.42 nd nd L I [72,78] 7.59 9.02 6.06 9.0 6.01 9.0 6.0 9.0 nd nd L J [72,78] 8.53 9.13 6.86 9.0 6.12 9.0 6.11 9.0 nd nd L K c, [62] 8.89 9.26 nd nd nd nd 6.35 9.0 nd nd Histidine [84] 8.72 9.02 WT-CAII [85] resent the chelators for which the largest differences in the pM values (at least ∼ three orders of magnitude difference) are observed when comparing the pCu II to the pZn II , pNi II , pCo II and pGa III values. To point out the potential of these chelators in PET imaging, these thermodynamic data were compared for two biological systems, namely the carbonic anhydrase and histidine.…”

Complex formation of copper(ii), nickel(ii) and zinc(ii) with ethylophosphonoacetohydroxamic acid: solution speciation, synthesis and structural characterization

“…1, 22,26 The phosphonic proton dissociation occurs much below pH 2 and the constant corresponding to this process could not be determined under our experimental conditions. [38][39][40] The potentiometric studies of Cu(II) (oxygen) Cu(II) CT transitions, 41,42 (Table 1, Figure S1). The parameters of corresponding EPR spectra (A II = 149 G and g II = 2.34) (Table 1, Fig.…”