Table 7.
The stability constants of nickel(II) complexes of peptides containing one cysteinyl residue (T=298 K, I=0.2 M).
|
logβ |
Ac‐AAAC‐NH2 |
Ac‐SAAC‐NH2 |
Ac‐DAAC‐NH2 [33] |
Ac‐HAAC‐NH2 [34] |
Ac‐CGAA‐NH2 |
Ac‐CGAK‐NH2 |
Ac‐CGAD‐NH2 |
Ac‐CGAH‐NH2 |
|---|---|---|---|---|---|---|---|---|
|
[NiH2L2] |
|
|
|
|
|
28.15(6) |
|
|
|
[NiL2] |
|
|
|
9.1 |
7.60(8) |
|
7.7(1) |
7.9(2) |
|
[NiLH] |
|
|
|
11.2 |
|
14.36(9) |
|
|
|
[NiL] |
3.3(1) |
|
3.81 |
5.17 |
4.09(9) |
|
4.3(1) |
4.44(7) |
|
[NiH−2L] |
−11.73(2) |
−12.01(9) |
−11.78(3) |
−10.81 |
−12.90(4) |
−11.44(1) |
−12.49(4) |
−11.80(4) |
|
[NiH−3L] |
−19.83(2) |
−19.36(2) |
−20.60(4) |
−21.53 |
−22.11(4) |
−22.24(5) |
−21.55(5) |
−20.77(6) |
|
pK(amide)12 |
7.52 |
|
7.80 |
7.99 |
8.38 |
|
8.50 |
8.12 |
|
pK(amide)3 |
8.10 |
7.35 |
8.82 |
10.72 |
9.06 |
|
9.21 |
8.97 |
|
pK(amide)av. |
7.71 |
|
8.14 |
8.90 |
8.73 |
8.60 |
8.60 |
8.40 |