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Updated: Apr 28, 2026

Author Spotlight: Exploring Cellular Processes by Modeling Ligands in Cryo-EM Maps
Published on: July 19, 2024
Validity of ligand efficiency metrics
Christopher W Murray1, Daniel A Erlanson2, Andrew L Hopkins3
1Astex Pharmaceuticals , 436 Cambridge Science Park, Milton Road, Cambridge CB4 0QA, U.K.
Abstract:
A recent viewpoint article (Improving the plausibility of success with inefficient metrics. ACS Med. Chem. Lett. 2014, 5, 2-5) argued that the standard definition of ligand efficiency (LE) is mathematically invalid. In this viewpoint, we address this criticism and show categorically that the definition of LE is mathematically valid. LE and other metrics such as lipophilic ligand efficiency (LLE) can be useful during the multiparameter optimization challenge faced by medicinal chemists.
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