J Mass Spectrom 2000 Sep;35(9):1112-20

Isolation from rat urine and human liver microsomes and identification by
electrospray and nanospray tandem mass spectrometry of new malagashanine
metabolites.

Rafatro H, Verbeeck RK, Gougnard TY, De Jonghe PJ, Rasoanaivo P, Laurent A,
Lhoest G

Laboratoire of Pharmacologie Generale et de Pharmacocinetique, Faculte des
Sciences, Universite d'Antananarivo, Antananarivo, Madagascar.

[Medline record in process]

Malagashanine has been isolated from indigenous madagascan Strychnos myrtoides
alkaloids used traditionally to treat malaria. This alkaloid was found to
enhance the action of chloroquine against chloroquine-resistant strains of
Plasmodium falciparum when combined with classical antimalarial drugs
(chloroquine, quinine). The present study was carried out in order to
investigate by electrospray mass and tandem mass spectrometry and NMR
spectroscopy the structure of two new metabolites isolated from rat urine and
human liver microsomes. We were able to demonstrate the presence of two new
metabolites of malagashanine corresponding to a malagashanine N-demethylated
metabolite and to the oxidation of malagashanine in the alpha-position of the
N-methyl group to produce a carbinolamine function. The latter metabolite may be
subject to ring and open-chain tautomerism effects and dimeric species were
detected in the electrospray mass spectrum. Copyright 2000 John Wiley & Sons,
Ltd.

PMID: 11006605, UI: 20463468