Table 4.

pM values calculated for different Cu²⁺ and Fe³⁺/(3,4-HPs) systems based on 3-hydroxy-4-pyridinone ligands and similar structures’ ligands at pH = 7.4 from stability constants reported in the literature.

Mn+	Ligand	pM	Ref.	Mn+	Ligand	pM	Ref.
Cu2+	H2(L1)	8.60	This work	Fe3+	H2(L4)	21.90 3	[31]
Cu2+	H2(L2)	11.00	This work	Fe3+	Deferiprone	20.70 1	[34]
Cu2+	H2(L3)	11.10	This work	Fe3+	H2(S1)	20.59 1	[38]
Cu2+	H2(L4)	10.90	This work	Fe3+	H2(S2)	20.19 6	[39]
Cu2+	H2(L5)	8.20	This work	Fe3+	H2(S3)	19.97 6	[39]
Cu2+	Deferiprone	10.69 1	[34]	Fe3+	L-Aspartic acid	15.63 4	[22]
Cu2+	L-Aspartic acid	7.842	[22]	Fe3+	L-Ornithine	15.64 5	[37]
Cu2+	AcNPrHP	10.40 1	[35]	Al3+	H2(L2)	14.20 2	[13]
Fe3+	H2(L2)	24.38	This work	Al3+	H2(L5)	13.17 2	[13]
Fe3+	H2(L5)	23.98	This work	Zn2+	H2(L2)	6.03 2	[19]
Fe3+	H2(L1)	19.90 3	[32]	Zn2+	H2(L5)	8.28 2	[19]

¹I = 0.10 mol L⁻¹ in KCl_(aq), T = 298.15 K; ² I = 0.15 mol L⁻¹ in NaCl_(aq), T = 298.15 K; ³ I = 0.10 mol L⁻¹ in KNO_3(aq), T = 298.15 K; ⁴ I = 1.00 mol L⁻¹ in Na⁺ ionic medium, T = 293.15 K; ⁵ I = 0.10 mol L⁻¹ in KNO_3(aq), T = 293.15 K; ⁶ I = 0.10 mol L⁻¹ in MOPS (3-(N-morpholino)propanesulphonic acid) buffer at pH = 7.4, T = 298.15 K.