Pose, duplicate, then elaborate: Steps towards increased affinity for inhibitors targeting the specificity surface of the Pim-1 kinase.
Heyder, L., Hochban, P.M.M., Taylor, C., Chevillard, F., Siefker, C., Iking, C., Borchardt, H., Aigner, A., Klebe, G., Heine, A., Kolb, P., Diederich, W.E.(2023) Eur J Med Chem 245: 114914-114914
- PubMed: 36410167 
- DOI: https://doi.org/10.1016/j.ejmech.2022.114914
- Primary Citation of Related Structures:  
7QB2, 7QFM, 7Z6U, 8AFR - PubMed Abstract: 
In this study, fragment-sized hits binding to Pim-1 kinase with initially modest affinity were further optimized by combining computational, synthetic and crystallographic expertise, eventually resulting in potent ligands with affinities in the nanomolar range that address rarely-targeted regions of Pim-1 kinase. Starting from a set of crystallographically validated, chemically distinct fragments that bind to Pim-1 kinase but lack typical nucleotide mimetic structures, a library of extended fragments was built by exhaustive in silico reactions. After docking, minimization, clustering, visual inspection of the top-ranked compounds, and evaluation of ease of synthetic accessibility, either the original compound or a close derivative was synthesized and tested against Pim-1. For compounds showing the highest degree of Pim-1 inhibition the binding mode was determined crystallographically. Following a structure-guided approach, these were further optimized in a subsequent design cycle improving the compound's initial affinity by several orders of magnitude while synthesizing only a comparatively modest number of derivatives. The combination of computational and experimental approaches resulted in the development of a reasonably potent, novel molecular scaffold for inhibition of Pim-1 that targets specific surface regions, such as the interaction with R122 and P123 of the hinge region, which has been less frequently investigated in similar studies.
Organizational Affiliation: 
Institut für Pharmazeutische Chemie, Zentrum für Tumor und Immunbiologie, Philipps-Universität Marburg, Hans-Meerwein-Straße 3, 35032, Marburg, Germany.