Phase I reaction

{
  "id": "MLC-T-CHM-008738",
  "term": "Phase I reaction",
  "field": "Chemistry",
  "definition": "A metabolic transformation of a xenobiotic or endogenous compound that introduces or unmasks a polar functional group, such as hydroxyl, carboxyl, or amino groups. These reactions, including oxidation, reduction, and hydrolysis, typically make the compound more water-soluble and prepare it for subsequent phase II conjugation reactions. Cytochrome P450 enzymes are frequently involved in these biotransformations.",
  "subject": "Chemistry and Human Health",
  "see_also": [
    "enzymes",
    "hydration",
    "hydrolysis",
    "organelles",
    "oxidation"
  ],
  "references": [
    "PAC, 2004, 76, 1033. 'Glossary of terms used in toxicokinetics (IUPAC Recommendations 2003)' on page 1064 (https://doi.org/10.1351/pac200476051033)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/phase-i-reaction/"
}