Exo-selective intermolecular Diels-Alder reaction by PyrI4 and AbnU on non-natural substrates.

ABSTRACT: The 100-year-old Diels-Alder reaction (DAr) is an atom economic and elegant organic chemistry transformation combining a 1,3-diene and a dienophile in a [4+2] cycloaddition leading to a set of products with several stereo centres and multiple stereoisomers. Stereoselective [4+2] cycloaddition is a challenge. Here, we describe two natural enzymes, PyrI4 and AbnU performing stereospecific intermolecular DAr on non-natural substrates. AbnU catalyses a single exo-stereoisomer by 32-fold higher than the background. PyrI4 catalyses the same stereoisomer (15-fold higher) as a major component (>50%). Structural, biochemical and fluorescence studies indicate that the dienophile enters first into the β-barrel of the enzymes followed by the 1,3-diene, yielding a stereospecific product. However, if so

SUBMITTER: Kashyap R 

PROVIDER: S-EPMC9814550 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature