Exploring the chiral space within the active site of alpha-thrombin with a constrained mimic of D-Phe-Pro-Arg--design, synthesis, inhibitory activity, and X-ray structure of an enzyme-inhibitor complex
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Updated: Aug 10, 2026

Modeling an Enzyme Active Site using Molecular Visualization Freeware
Published on: December 25, 2021
S Hanessian1, E Balaux, D Musil
1Department of Chemistry, Université de Montréal, Québec, Canada. hanessia@ere.unmontreal.ca
Abstract:
An indolizidinone motif with strategically placed substitutents was designed and synthesized as a constrained mimic of D-Phe-Pro-Arg. Low nanomolar inhibition of alpha-thrombin validates the design elements in this inhibitor which also exhibits a 20-fold selectivity for thrombin versus trypsin. An X-ray crystal structure of the inhibitor with alpha-thrombin shows the expected interactions with key amino acids within the active site and some notable changes in positions.
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