FIG 3.

PZQ1 is metabolized by CYP 450, resulting in PZQ4 as the main product and other minor enantiomers such as PZQ5 and PZQ6. In addition, enantiomers of PZQ1 also undergo metabolism. Bold green and blue arrows indicate major metabolites of PZQ enantiomers PZQ2 and PZQ3, respectively. PZQ2 is mainly metabolized into trans- and cis-4-OH-PZQ (PZQ6), whereas PZQ3 is mainly metabolized into other mono- or dihydroxylated forms of PZQ1 and, to a less extent, into trans- and cis-4-OH-PZQ (PZQ5, PZQ6). P450 enzymes perform these transformations.