AssayIndex
Cross-section

PT-141 (Bremelanotide) impurity profile

Every named species the index has reported alongside PT-141 (Bremelanotide), 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.

200 recordsmedian 99.31 %spec 98.5 %
Median total impurities 0.69% n=200
Median largest single 0.36% n=200
Worst single observed 1.58% n=200
Named species observed 4 / 4 n=4
Named speciesΔRT (min)Δ mass (Da)Seen inMedian % areaMax % area
melanotan II (C-terminal amide, −1 Da)+0.32-0.98490%0.181.58
linear precursor (+18 Da)-0.70+18.01190%0.111.03
oxidised Trp (+16 Da)-0.34+15.99586%0.111.56
des-acetyl (−42 Da)-0.46-42.01183%0.111.01

melanotan II (C-terminal amide, −1 Da)

Retention offset from the main peak
+0.32 min on RG-2
Mass difference
-0.984 Da
Reported in
180 of 200 records (90 %)
Level when reported
median 0.18 %, max 1.58 %
Resolution requirement
Baseline-resolved on the reference method.

linear precursor (+18 Da)

Retention offset from the main peak
-0.70 min on RG-2
Mass difference
+18.011 Da
Reported in
180 of 200 records (90 %)
Level when reported
median 0.11 %, max 1.03 %
Resolution requirement
Baseline-resolved on the reference method.

oxidised Trp (+16 Da)

Retention offset from the main peak
-0.34 min on RG-2
Mass difference
+15.995 Da
Reported in
171 of 200 records (86 %)
Level when reported
median 0.11 %, max 1.56 %
Resolution requirement
Baseline-resolved on the reference method.

des-acetyl (−42 Da)

Retention offset from the main peak
-0.46 min on RG-2
Mass difference
-42.011 Da
Reported in
166 of 200 records (83 %)
Level when reported
median 0.11 %, max 1.01 %
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