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Thiols Act as Methyl Traps in the Biocatalytic Demethylation of Guaiacol Derivatives.

ABSTRACT: Demethylating methyl phenyl ethers is challenging, especially when the products are catechol derivatives prone to follow-up reactions. For biocatalytic demethylation, monooxygenases have previously been described requiring molecular oxygen which may cause oxidative side reactions. Here we show that such compounds can be demethylated anaerobically by using cobalamin-dependent methyltransferases exploiting thiols like ethyl 3-mercaptopropionate as a methyl trap. Using just two equivalents of this reagent, a broad spectrum of substituted guaiacol derivatives were demethylated, with conversions mostly above 90 %. This strategy was used to prepare the highly valuable antioxidant hydroxytyrosol on a one-gram scale in 97 % isolated yield.

SUBMITTER: Pompei S

PROVIDER: S-EPMC8361964 | biostudies-literature |

REPOSITORIES: biostudies-literature

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| S-EPMC2814115 | biostudies-literature

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