Phase I reactions

PHASE - I REACTIONS

Reaction

Example

Oxidative reactions
N- and O- dealkylation phenacetin, morphine
Aliphatic and aromatic hydroxylation Phenobarbital, phenytoin
N-Oxidation Guanethidine, acetaminophen

Sulphoxide formation

 Chlorpromazine
Deamination of amine Amphetamine
Desulfuration Thiobarbital, parathion
Hydrolysis of esters and amides Procaine
Reduction

a. Azo reduction

Prontosil

b. Nitro reduction hloramphenicol

Chloramphenicol

  • Non-microsomal reactions
  • Mono Amine Oxidase (for biogenic and other amines)
  • Esterases (for choline and dietary esters)
  • Dehydrogenases (for alcohols and aldehydes)
Last modified: Wednesday, 25 April 2012, 5:55 AM