EPR evidence for the involvement of free radicals in the iron-catalysed decomposition of qinghaosu (artemisinin) and some derivatives; antimalarial action of some polycyclic endoperoxides

A R Butler; B C Gilbert; P Hulme; L R Irvine; L Renton; A C Whitwood

doi:10.3109/10715769809066884

EPR evidence for the involvement of free radicals in the iron-catalysed decomposition of qinghaosu (artemisinin) and some derivatives; antimalarial action of some polycyclic endoperoxides

Free Radic Res. 1998 May;28(5):471-6. doi: 10.3109/10715769809066884.

Authors

A R Butler¹, B C Gilbert, P Hulme, L R Irvine, L Renton, A C Whitwood

Affiliation

¹ School of Chemistry, University of St. Andrews, Fife, Scotland.

PMID: 9702527
DOI: 10.3109/10715769809066884

Abstract

EPR experiments confirm that reaction of qinghaosu and some related endoperoxides with Fe2+ in aqueous acetonitrile leads to the production of carbon-centred radicals derived by rapid rearrangement of first-formed cyclic alkoxyl radicals. Signals obtained from qinghaosu itself with spin-traps DMPO and DBNBS are assigned to the adducts (15) and (16), a finding which accounts for the formation of the major products (11) and (14).

MeSH terms

Antimalarials / metabolism*
Antimalarials / pharmacology
Artemisia / chemistry
Artemisinins*
Catalysis
Drugs, Chinese Herbal / metabolism*
Drugs, Chinese Herbal / pharmacology
Electron Spin Resonance Spectroscopy / methods
Electron Transport
Ferric Compounds / chemistry*
Free Radicals / metabolism*
Iron / metabolism*
Plants, Medicinal
Polycyclic Compounds / pharmacology
Reducing Agents / chemistry
Sesquiterpenes / metabolism*
Sesquiterpenes / pharmacology

Substances

Antimalarials
Artemisinins
Drugs, Chinese Herbal
Ferric Compounds
Free Radicals
Polycyclic Compounds
Reducing Agents
Sesquiterpenes
artemisinin
Iron