Melanotan II impurity profile
Every named species the index has reported alongside Melanotan II, 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
0.76%
n=186
Median largest single
0.36%
n=186
Worst single observed
2.11%
n=186
Named species observed
5 / 5
n=5
| Named species | ΔRT (min) | Δ mass (Da) | Seen in | Median % area | Max % area |
|---|---|---|---|---|---|
| [L-Phe7]-diastereomer | -0.16 | mass-identical | 92% | 0.08 | 0.98 |
| linear (open-lactam) precursor (+18 Da) | -0.74 | +18.011 | 91% | 0.21 | 1.19 |
| oxidised Trp (+16 Da) | -0.36 | +15.995 | 87% | 0.09 | 2.11 |
| des-acetyl MT-II (−42 Da) | -0.48 | -42.011 | 85% | 0.09 | 1.14 |
| MT-II dimer (head-to-tail) | +2.35 | +1023.540 | 71% | 0.06 | 0.82 |
[L-Phe7]-diastereomer
- Retention offset from the main peak
- -0.16 min on RG-2
- Mass difference
- mass-identical — chromatography only
- Reported in
- 171 of 186 records (92 %)
- Level when reported
- median 0.08 %, max 0.98 %
- Resolution requirement
- A gradient long enough to separate it. No mass spectrometer will.
linear (open-lactam) precursor (+18 Da)
- Retention offset from the main peak
- -0.74 min on RG-2
- Mass difference
- +18.011 Da
- Reported in
- 169 of 186 records (91 %)
- Level when reported
- median 0.21 %, max 1.19 %
- Resolution requirement
- Baseline-resolved on the reference method.
oxidised Trp (+16 Da)
- Retention offset from the main peak
- -0.36 min on RG-2
- Mass difference
- +15.995 Da
- Reported in
- 162 of 186 records (87 %)
- Level when reported
- median 0.09 %, max 2.11 %
- Resolution requirement
- Baseline-resolved on the reference method.
des-acetyl MT-II (−42 Da)
- Retention offset from the main peak
- -0.48 min on RG-2
- Mass difference
- -42.011 Da
- Reported in
- 159 of 186 records (85 %)
- Level when reported
- median 0.09 %, max 1.14 %
- Resolution requirement
- Baseline-resolved on the reference method.
MT-II dimer (head-to-tail)
- Retention offset from the main peak
- +2.35 min on RG-2
- Mass difference
- +1023.540 Da
- Reported in
- 132 of 186 records (71 %)
- Level when reported
- median 0.06 %, max 0.82 %
- Resolution requirement
- Baseline-resolved on the reference method.
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.
- Trp oxidation
- lactam hydrolysis reopening the ring