KPV impurity profile
Every named species the index has reported alongside KPV, how often, at what level, and what its presence implies about the synthesis or the handling. Reporting threshold is 0.05 % area; anything below it is invisible to this page and is silently added to the main peak.
Median total impurities
0.79%
n=94
Median largest single
0.40%
n=94
Worst single observed
1.57%
n=94
Named species observed
4 / 4
n=4
| Named species | ΔRT (min) | Δ mass (Da) | Seen in | Median % area | Max % area |
|---|---|---|---|---|---|
| acetyl-KPV (+42 Da) | +0.30 | +42.011 | 95% | 0.12 | 1.57 |
| Lys-Pro dipeptide (−99 Da) | -0.36 | -99.068 | 91% | 0.12 | 1.26 |
| Pro-Val dipeptide (−128 Da) | -0.44 | -128.095 | 86% | 0.12 | 1.46 |
| diketopiperazine (−18 Da) | +0.15 | -18.011 | 83% | 0.12 | 1.22 |
acetyl-KPV (+42 Da)
- Retention offset from the main peak
- +0.30 min on RG-2
- Mass difference
- +42.011 Da
- Reported in
- 89 of 94 records (95 %)
- Level when reported
- median 0.12 %, max 1.57 %
- Resolution requirement
- Baseline-resolved on the reference method.
Lys-Pro dipeptide (−99 Da)
- Retention offset from the main peak
- -0.36 min on RG-2
- Mass difference
- -99.068 Da
- Reported in
- 86 of 94 records (91 %)
- Level when reported
- median 0.12 %, max 1.26 %
- Resolution requirement
- Baseline-resolved on the reference method.
Pro-Val dipeptide (−128 Da)
- Retention offset from the main peak
- -0.44 min on RG-2
- Mass difference
- -128.095 Da
- Reported in
- 81 of 94 records (86 %)
- Level when reported
- median 0.12 %, max 1.46 %
- Resolution requirement
- Baseline-resolved on the reference method.
diketopiperazine (−18 Da)
- Retention offset from the main peak
- +0.15 min on RG-2
- Mass difference
- -18.011 Da
- Reported in
- 78 of 94 records (83 %)
- Level when reported
- median 0.12 %, max 1.22 %
- Resolution requirement
- Close-eluting — resolution below 1.2 is common and the peaks merge on short gradients.
Degradation pathways
Degradants are a handling finding rather than a synthesis finding. A lot that shipped clean and arrived oxidised tells you about the courier, not the chemist.
- diketopiperazine formation from the Lys-Pro N-terminus
- no oxidative liability