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Direct Conversion of Hydrazones to Amines using Transaminases

ABSTRACT: Abstract Transaminase enzymes (TAms) have been widely used for the amination of aldehydes and ketones, often resulting in optically pure products. In this work, transaminases were directly reacted with hydrazones in a novel approach to form amine products. Several substrates were investigated, including those with furan and phenyl moieties. It was determined that the amine yields increased when an additional electrophile was added to the reaction mixture, suggesting that they can sequester the hydrazine released in the reaction. Pyridoxal 5’‐phosphate (PLP), a cofactor for transaminases, and polyethylene glycol (PEG)‐aldehydes were both found to increase the yield of amine formed. Notably, the amination of (S)‐(−)‐1‐amino‐2‐(methoxymethyl)pyrrolidine (SAMP) hydrazones gave promising results as a method to form chiral β‐substituted amines in good yield. The reaction of aldehydes and ketones with transaminases has been widely used for producing amines. Here, a new transformation between hydrazones and transaminases was explored. Several substrates were investigated, forming a variety of amines in good yields. Amine yields were found to improve by the addition of electrophiles, thought to ‘trap’ the hydrazine released in the reaction.

SUBMITTER: Carter E

PROVIDER: S-EPMC9292518 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature

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