PMID: 9540107Apr 16, 1998Paper

Photoreactivity of biologically active compounds, XIV: influence of oxygen on light induced reactions of primaquine

Die Pharmazie
S KristensenH H Tønnesen

Abstract

The influence of molecular oxygen and oxygen radicals on the photoreactivity of the antimalarial drug primaquine (PQ) has been investigated. Oxygen is directly involved in photodecomposition of the drug. Flushing with helium gas prior to and during irradiation to suppress the oxygen level of the medium, retards the degradation rate of PQ (followed by HPLC) and leads to the formation of only two degradation products (identified by MS) compared to eight main- and several minor products under normal atmospheric conditions. Flushing with oxygen gas prior to and during irradiation to increase the oxygen content of the medium accelerates the degradation rate of PQ. PQ produces oxygen radicals (hydroxyl and superoxide) during photolysis, while the photoproducts of PQ seem likely to induce singlet oxygen formation (detected by addition of radical scavengers). Sensitization reactions involving singlet oxygen lead to decomposition of PQ (followed by HPLC). On the basis of our results, photochemical reaction mechanisms of PQ are postulated and discussed. At physiological conditions (aqueous, neutral pH, oxygen rich) PQ has a large potential to decompose after light absorption. The photoreaction seems to be initiated at the quinoline nitro...Continue Reading

Related Concepts

Related Feeds

Antimalarial Agents (ASM)

Antimalarial agents, also known as antimalarials, are designed to prevent or cure malaria. Discover the latest research on antimalarial agents here.

Antimalarial Agents

Antimalarial agents, also known as antimalarials, are designed to prevent or cure malaria. Discover the latest research on antimalarial agents here.

Related Papers

Photochemical & Photobiological Sciences : Official Journal of the European Photochemistry Association and the European Society for Photobiology
L F Vieira FerreiraT J F Branco
Journal of Photochemistry and Photobiology. B, Biology
Aurélien S TrivellaClaire Richard
© 2022 Meta ULC. All rights reserved