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 some critical interactions are disrupted to increase the catalytic efficiency, stereoselectivity is compromised. Since it is established that natural enzymes can carry out intermolecular DAr on non-natural substrates, several hundreds of Diels-Alderases available in nature could be explored.

Diels-Alderases remain rare in nature, particularly those catalysing intermolecular reactions. Here two natural Diels-Alderases are shown to catalyse exo-selective intermolecular Diels-Alder reactions on non-natural substrates.

Details

Title
Exo-selective intermolecular Diels–Alder reaction by PyrI4 and AbnU on non-natural substrates
Author
Kashyap Rajnandani 1   VIAFID ORCID Logo  ; Yerra Naga Veera 2 ; Oja Joachyutharayalu 3 ; Sandeepchowdary, Bala 1   VIAFID ORCID Logo  ; Potuganti Gal Reddy 4 ; Thota Jagadeshwar Reddy 2 ; Manjula, Alla 4   VIAFID ORCID Logo  ; Debnath, Pal 5 ; Addlagatta, Anthony 1   VIAFID ORCID Logo 

 CSIR-Indian Institute of Chemical Technology, Department of Applied Biology, Hyderabad, India (GRID:grid.417636.1) (ISNI:0000 0004 0636 1405); Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India (GRID:grid.469887.c) (ISNI:0000 0004 7744 2771) 
 Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India (GRID:grid.469887.c) (ISNI:0000 0004 7744 2771); CSIR-Indian Institute of Chemical Technology, Analytical and Structural Chemistry Department, Hyderabad, India (GRID:grid.417636.1) (ISNI:0000 0004 0636 1405) 
 CSIR-Indian Institute of Chemical Technology, Fluoro-Agrochemicals Department, Hyderabad, India (GRID:grid.417636.1) (ISNI:0000 0004 0636 1405) 
 Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India (GRID:grid.469887.c) (ISNI:0000 0004 7744 2771); CSIR-Indian Institute of Chemical Technology, Fluoro-Agrochemicals Department, Hyderabad, India (GRID:grid.417636.1) (ISNI:0000 0004 0636 1405) 
 Indian Institute of Science, Department of Computational and Data Sciences, Bengaluru, India (GRID:grid.34980.36) (ISNI:0000 0001 0482 5067) 
Publication year
2021
Publication date
2021
Publisher
Nature Publishing Group
e-ISSN
23993669
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2557677197
Copyright
© The Author(s) 2021. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.