Fosinoprilat and Fosinopril
Fosinoprilat proved to have the same problem as enalaprilat and the other carboxylate-containing ACE inhibitors (namely poor oral bioavailability). Addition of a hydrophobic side-chain modulated the ionisation characteristics of the molecule making it more bioavailable. Fosinopril is administered as a prodrug and is converted in vivo to the active form fosinoprilat.
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