Table 2.

Stability and protonation constants as well as pMn values for the Mn(II) complexes (I = 0.15 M NaCl, 25 °C).

	log KML	log $K_{\text{ML}}^{\text{H}}$	log $K_{\text{MHL}}^{\text{H}}$	log $K_{\text{MH}2\text{L}}^{\text{H}}$	log $K_{\text{ML}}^{\text{OH}}$	pMn[h]
DO3A	16.55 (4)	4.26 (2)	–	–	–	8.66
DO3AMH	11.69 (2)	–	–	–	–	7.32
DO3P	17.45 (2)	8.06 (2)	7.05 (1)	5.31 (2)	–	6.43
ODO3A	13.88 (1)	2.77 (5)	–	–	–	8.57
PCTA	16.83 (1) 16.64 (7)[a]	1.96(1)	–	–	–	9.74
PC3AMH	11.94(3) 11.78 (8)[a]	–	–	–	10.90 (4)	7.77
PC3AMGly	13.20 (1)	3.98 (1)	3.14 (1)	2.87 (1)	10.67 (2)	8.37
PC3AMPip	14.05 (2)	–	–	–	11.63 (2)	8.86
DOTA[b]	19.44	3.96	–	–	–	9.02
DOTMA[c]	18.37[a]	4.56[a]	–	–	–	8.69
DOTAM	11.96 (1)	–	–	–	–	8.60
DOTP[d]	18.98 (1)	8.09 (1)	7.79 (1)	6.74 (1)	–	6.43
trans-DO2A[e]	14.64	4.40	–	–	–	6.52
cis-DO2A[e]	15.68	4.15	–	–	–	7.27
cis-DO2AMMe2, [f]	12.64	–	–	–	–	6.98
cis-Bz2DO2AMMe2, [f]	11.54	–	–	–	10.44	6.00
cis-DO2AMBz2, [g]	10.72	–	–	–	9.44	6.69

^[a]1H-relaxometry;

^[b]I = 0.1 M KCl (Takács et al., 2014);

^[c]Tircsó and Woods (in preparation);

^[d]the 4^th protonation constant of the complex is (log K${}_{\text{MH}3\text{L}}^{\text{H}}$ = 5.02 (1);]

^[e]Garda et al. (2016);

^[f]I = 0.1 M KCl (Forgács et al., 2016);

^[g]I = 0.1 M KCl (Forgács et al., 2017);

^[h]The pMn values were calculated at pH = 7.4, c_M = c_L = 10⁻⁵ M by using the conditions as suggested by Drahos et al. (2010).