Extended Data Fig. 2: Chemo- and stereoselectivity.
From: Efficient Lewis acid catalysis of an abiological reaction in a de novo protein scaffold
a, HPLC chromatogram (at 350 nm) and crystal structure (Supplementary Table 11) of the racemic exo Diels-Alder product 3 (only one enantiomer is shown for clarity). b, HPLC chromatogram of the racemic hetero-Diels-Alder products 4 and crystal structure of the enzymatically synthesised (4 R,6 R)-endo hetero-Diels-Alder product. The hydrogen atoms on the central six-membered ring are shown for the X-ray crystal structures in a and b. c, HPLC analysis of the Diels-Alder (3.36 min) and hetero-Diels-Alder (3.06 min) product profile under different conditions. d, Chiral HPLC chromatograms of the hetero-Diels-Alder reaction products from reactions without protein (grey) and reactions catalysed by DA0 (pink) and DA7 (orange). Retention times vary due to different column temperatures (40 °C vs room temperature).
