AssayIndex
Cross-section

Pinealon impurity profile

Every named species the index has reported alongside Pinealon, 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.

3 recordsmedian 99.93 %spec 99.0 %
Median total impurities 0.07% n=3
Median largest single 0.04% n=3
Worst single observed 0.14% n=3
Named species observed 4 / 4 n=4
Named speciesΔRT (min)Δ mass (Da)Seen inMedian % areaMax % area
Glu-Asp dipeptide (−156 Da)-0.30-156.101100%0.030.04
aspartimide (−18 Da)+0.14-18.01167%0.07, 0.040.07
pyroglutamate (−18 Da)+0.18-18.01167%0.03, 0.030.03
Asp-Arg dipeptide (−129 Da)-0.34-129.04333%0.140.14

Glu-Asp dipeptide (−156 Da)

Retention offset from the main peak
-0.30 min on RG-2
Mass difference
-156.101 Da
Reported in
3 of 3 records (100 %)
Level when reported
median 0.03 %, max 0.04 %
How it separates
Baseline-resolved on the reference method.

aspartimide (−18 Da)

Retention offset from the main peak
+0.14 min on RG-2
Mass difference
-18.011 Da
Reported in
2 of 3 records (67 %)
Level when reported
0.07, 0.04 %
How it separates
Close-eluting on the reference method, and merged with the main peak on a short gradient. The index prints the resolution figure for such a pair and applies no criterion to it — where the two are not separated, what matters is that the integration convention is stated.

pyroglutamate (−18 Da)

Retention offset from the main peak
+0.18 min on RG-2
Mass difference
-18.011 Da
Reported in
2 of 3 records (67 %)
Level when reported
0.03, 0.03 %
How it separates
Close-eluting on the reference method, and merged with the main peak on a short gradient. The index prints the resolution figure for such a pair and applies no criterion to it — where the two are not separated, what matters is that the integration convention is stated.

Asp-Arg dipeptide (−129 Da)

Retention offset from the main peak
-0.34 min on RG-2
Mass difference
-129.043 Da
Reported in
1 of 3 records (33 %)
Level when reported
0.14 %
How it separates
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.

  • N-terminal pyroglutamate cyclisation
  • aspartimide