Table 1. Protonation and complex formation constants for DFO, DFP and DFX with iron(III), copper(II) and zinc(II) from literature.

DFO			DFP			DFX
Species	log β	pK	Species	log β	pK	Species	log β	pK
[LH]2-	[20]10.84	10.84	[LH]0	[14]9.82	9.82	[LH]2-	[21]10.61	10.61
[LH2]-	20.3	9.4	[LH2]+	13.48	3.66	[LH2]-	19.61	9.00
[LH3]0	29.3	9.0				[LH3]0	23.32	3.71
[LH4]+	37.6	8.3
[FeLH]+	[22]41.01	10.61				[FeLH]+	[21, 23]24.3	2.3
[FeL]0	30.4		[FeL]2+	[14]15.01		[FeL]0	22.0
						[FeL2H2]-	43.4	2.2
						[FeL2H]2-	41.2	4.3
			[FeL2]+	27.30		[FeL2]3-	36.9
			[FeL3]0	37.43
[ZnLH3]2+	[20]33.4	5.2
[ZnLH2]+	28.17	7.77
[ZnLH]0	20.4	10.1
[ZnL]-	10.32		[ZnL]+	[24] 7.24		[ZnL]-	[21, 23]12.1
						[ZnL2]-4	16
			[ZnL2]0	13.55	11.25
			[ZnL2H-1]-1	2.30
			[ZnL3]-1	15.2
[CuLH3]2+	[20]36.99	3.89
[CuLH2]+	33.1	9.1
[CuLH]0	23.98	10.24
[CuL]-	13.74		[CuL]+	[14]10.42		[CuL]-	[21, 23]17.6
						[CuL2]-4	22.4
			[CuL2H]+	21.98	2.89
			[CuL2]0	19.09	10.60
			[CuL2H-1]-1	8.49
[Cu2LH]2+	32.09