Pharmaceutisch Weekblad

, Volume 7, Issue 3, pp 121–124 | Cite as

Degradation products of the promethazine radical cation

  • N. J. De Mol
  • Jac Koenen
Original Articles


The degradation products of the promethazine radical cation, generated from promethazine with horseradish peroxidase/H2O2, have been investigated. Several products have been identified which resulted from fission of the bond between the two ethanamine carbon atoms of the N10 side chain. The main product (approx. 90%) was identified as 10-formyl-5-oxophenothiazine. The likely structure of three minor products was also elucidated. The degradation of the promethazine radical cation is different from that of radical cations derived from the propanamine side chain containing phenothiazine drugs.


Public Health Internal Medicine Carbon Atom Degradation Product Radical Cation 
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Copyright information

© Royal Dutch Association for Advancement of Pharmacy 1985

Authors and Affiliations

  • N. J. De Mol
    • 1
  • Jac Koenen
    • 1
  1. 1.Department of Pharmacochemistry, Subfaculty of Pharmacy, Gorlaeus LaboratoriesState University of LeidenRA LeidenThe Netherlands

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