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Drug Metabolism Synthetic (Phase II) Reactions

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The ADME Encyclopedia

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Synonyms

Conjugation reactions; Phase 2 biotransformation; Phase 2 metabolism; Phase 2 reactions; Phase II biotransformation; Phase II metabolism; Phase II reactions; Synthetic metabolism; Synthetic reactions

Definition

In synthetic (or Phase II or conjugation) reactions, an endogenous or exogenous compound (the substrate of the reaction) is coupled to an endogenous conjugating moiety (sometimes called endocon). The conjugating moiety is usually polar and in the range of 100 to 300 Da (there are exceptions to this, though). The endocon is in general supplied by a cofactor (a coenzyme or co-substrate) where a high-energy chemical bond links the cofactor to the endocon. Synthetic reactions are almost always catalyzed by transferases [1]. The Phase II denomination comes from Williams’ classic nomenclature and can be misleading, as it reflects the notion of sequential metabolism, where the parent drug is converted to a primary (or first-generation) metabolite, which in turn is subjected...

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Authors and Affiliations

  1. Laboratory of Bioactive Research and Development (LIDeB), Department of Biological Sciences, Faculty of Exact Sciences, University of La Plata (UNLP), La Plata, Buenos Aires, Argentina

    Alan Talevi & Carolina L. Bellera

  2. Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), La Plata, Buenos Aires, Argentina

    Alan Talevi & Carolina L. Bellera

Authors
  1. Alan Talevi
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  2. Carolina L. Bellera
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Correspondence to Alan Talevi .

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  1. Laboratory of Bioactive Research and Development (LIDeB), Department of Biological Sciences, Faculty of Exact Sciences, University of La Plata (UNLP), La Plata, Buenos Aires, Argentina

    Alan Talevi

  2. Argentinean National Council of Scientific and Technical Research (CONICET) - CCT La Plata, La Plata, Buenos Aires, Argentina

    Alan Talevi

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Talevi, A., Bellera, C.L. (2021). Drug Metabolism Synthetic (Phase II) Reactions. In: The ADME Encyclopedia. Springer, Cham. https://doi.org/10.1007/978-3-030-51519-5_64-1

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  • DOI: https://doi.org/10.1007/978-3-030-51519-5_64-1

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  • Print ISBN: 978-3-030-51519-5

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