Bioprecursor Prodrugs & Chemical Delivery Systems PDF

Bioprecursor Prodrugs Phosphorylation example – (Note: Thymine contain CH3 instead of I) Chemical Delivery Systems Example: L-Dopa or Levodopa – Anti-Parkinsonism agent Larodopa® – Roche and Dopar® - Procter & Gamble Brain has a specific transport system for L-amino acids D...

Bioprecursor Prodrugs Phosphorylation example – (Note: Thymine contain CH3 instead of I) Chemical Delivery Systems Example: L-Dopa or Levodopa – Anti-Parkinsonism agent Larodopa® – Roche and Dopar® - Procter & Gamble Brain has a specific transport system for L-amino acids Dopamine does not cross the blood brain barrier efficiently, is rapidly metabolized by oxidative deamination, and can cause peripheral side effects  Pro-2-PAM is a dihydropyridine derivative that undergoes metabolic and chemical oxidation to yield the active drug 2-PAM as showing in the following scheme:  The amide hydrolysis step may be slower than the dihydropyridine oxidation step, and thus a reservoir of pyridinium amide precursor may be available for conversion to the active drug species.