FIG. 1.
Metabolism of bis(POC)-PMPA to PMPA. Stochiometrically, one molecule of bis(POC)-PMPA releases two molecules of isopropanol, carbon dioxide, and formaldehyde and one molecule of PMPA. Cleavage of the first ester group yields the intermediate metabolite [mono(POC)-PMPA]; cleavage of the second ester group gives the active drug PMPA.