title: Preparation of human drug metabolites using fungal peroxygenases.
abstract: The synthesis of hydroxylated and O- or N-dealkylated human drug metabolites (HDMs) via selective monooxygenation remains a challenging task for synthetic organic chemists. Here we report that aromatic peroxygenases (APOs; EC 1.11.2.1) secreted by the agaric fungi Agrocybe aegerita and Coprinellus radians catalyzed the H₂O₂-dependent selective monooxygenation of diverse drugs, including acetanilide, dextrorphan, ibuprofen, naproxen, phenacetin, sildenafil and tolbutamide. Reactions included the hydroxylation of aromatic rings and aliphatic side chains, as well as O- and N-dealkylations and exhibited different regioselectivities depending on the particular APO used. At best, desired HDMs were obtained in yields greater than 80% and with isomeric purities up to 99%. Oxidations of tolbutamide, acetanilide and carbamazepine in the presence of H₂¹⁸O₂ resulted in almost complete incorporation of ¹⁸O into the corresponding products, thus establishing that these reactions are peroxygenations. The deethylation of phenacetin-d₁ showed an observed intramolecular deuterium isotope effect [(k(H)/k(D))(obs)] of 3.1±0.2, which is consistent with the existence of a cytochrome P450-like intermediate in the reaction cycle of APOs. Our results indicate that fungal peroxygenases may be useful biocatalytic tools to prepare pharmacologically relevant drug metabolites.
authors: International Graduate School of Zittau (IHI Zittau), Department of Bio- and Environmental Sciences, Markt 23, 02763 Zittau, Germany.
authors: Marzena
authors: M
authors: Poraj-Kobielska
authors: Matthias
authors: M
authors: Kinne
authors: René
authors: R
authors: Ullrich
authors: Katrin
authors: K
authors: Scheibner
authors: Gernot
authors: G
authors: Kayser
authors: Kenneth E
authors: KE
authors: Hammel
authors: Martin
authors: M
authors: Hofrichter
mesh_terms: D000363:Agaricales / Q000201:enzymology*; D055362:Agrocybe / Q000201:enzymology*; D003640:Dealkylation; D006861:Hydrogen Peroxide / Q000737:chemistry; D006900:Hydroxylation; D007700:Kinetics; D006899:Mixed Function Oxygenases / Q000737:chemistry*; D010084:Oxidation-Reduction; D010103:Oxygen Isotopes; D004364:Pharmaceutical Preparations / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D010103:Oxygen Isotopes; D004364:Pharmaceutical Preparations; D006861:Hydrogen Peroxide; D006899:Mixed Function Oxygenases; C022333:peroxygenase