Hydroxynaphthoquinone atovaquon

Atovaquone, a hydroxynaphthoquinone, selectively inhibits the respiratory chain of protozoan mitochondria at the cytochrome bcl complex (complex III) by mimicking the natural substrate, ubiquinone. Inhibition of cytochrome bcl disrupts the mitochondrial electron transfer chain and leads to a breakdown of the mitochondrial membrane potential. Atovaquone is effective against all parasite stages in humans, including the liver stages. 

Atovaquone, a hydroxynaphthoquinone (Figure 52-2), was initially developed as an antimalarial agent, and as a component of Malarone is recommended for treatment and prevention of malaria. Atovaquone has also been approved by the FDA for the treatment of mild to moderate P jiroveci pneumonia. 

Atovaquone is a hydroxynaphthoquinone and was isolated from blood and plasma and analyzed on a C,g column (2 = 277 nm) using a 65/35 acetonitrile/ water (10 mM KH2PO4 at pH 7.0) mobile phase [1440]. The analysis was complete in <4 min with the atovaquone well separated from all other extracted compounds. A linear range of 0.25-15 pM with detection and quantitation limits of 30nM (S/N = 3) and 150nM (S/N = 10), respectively, were reported. 

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