AssayIndex
Cross-section

Enclomiphene citrate impurity profile

Every named species the index has reported alongside Enclomiphene citrate, 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.

55 recordsmedian 99.23 %spec 98.5 %
Median total impurities 0.77% n=55
Median largest single 0.40% n=55
Worst single observed 1.53% n=55
Named species observed 4 / 4 n=4
Named speciesΔRT (min)Δ mass (Da)Seen inMedian % areaMax % area
zuclomiphene (cis-isomer)-0.62mass-identical96%0.121.41
N-oxide (+16 Da)-0.88+15.99596%0.111.28
des-ethyl enclomiphene (−28 Da)-0.44-28.03184%0.181.40
free base (des-citrate)+0.02-192.02780%0.111.53

zuclomiphene (cis-isomer)

Retention offset from the main peak
-0.62 min on RG-2
Mass difference
mass-identical — chromatography only
Reported in
53 of 55 records (96 %)
Level when reported
median 0.12 %, max 1.41 %
Resolution requirement
A gradient long enough to separate it. No mass spectrometer will.

N-oxide (+16 Da)

Retention offset from the main peak
-0.88 min on RG-2
Mass difference
+15.995 Da
Reported in
53 of 55 records (96 %)
Level when reported
median 0.11 %, max 1.28 %
Resolution requirement
Baseline-resolved on the reference method.

des-ethyl enclomiphene (−28 Da)

Retention offset from the main peak
-0.44 min on RG-2
Mass difference
-28.031 Da
Reported in
46 of 55 records (84 %)
Level when reported
median 0.18 %, max 1.40 %
Resolution requirement
Baseline-resolved on the reference method.

free base (des-citrate)

Retention offset from the main peak
+0.02 min on RG-2
Mass difference
-192.027 Da
Reported in
44 of 55 records (80 %)
Level when reported
median 0.11 %, max 1.53 %
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.

  • cis/trans photoisomerisation — the compound isomerises in light back toward the clomiphene mixture
  • N-oxidation