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Medicinal Chemistry

Chemistry In Pictures

Chemistry in Pictures: Going through phases

by Brianna Barbu
August 18, 2022


A test tube with two different colored liquid layers: a blue layer on the bottom and an orange layer on top. There are long crystals at the bottom and a solid floating at the interface between the layers.
Credit: Matthew Holland

The product of this biphasic reaction is not soluble in either the organic solvent on top or the aqueous layer at the bottom. As the reaction proceeded, the product precipitated, collecting at the interface between the layers. Meanwhile, copper sulfate from the reaction’s catalyst accumulated at the bottom, forming spindly crystals that look like skeletal fingers reaching up from the depths. Excess starting material and other impurities stay dissolved. Matthew Holland, the chemist who ran the reaction and took this photo, is a medicinal chemistry doctoral student in the Brennan group at the University of Oxford. He’s working on software to predict new bioactive molecules for drug discovery. The molecule he made in this reaction is a precursor to a compound that his software predicted for inhibiting the main protease of the SARS-CoV-2 virus.

Submitted by Matthew Holland. Follow him on Twitter @matthewhollandm.

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