Structure-Based Design of Ultrapotent Tricyclic Ligands for FK506-Binding Proteins.
Krajczy, P., Meyners, C., Repity, M.L., Hausch, F.(2024) Chemistry 30: e202401405-e202401405
- PubMed: 38837733 
- DOI: https://doi.org/10.1002/chem.202401405
- Primary Citation of Related Structures:  
9EY3, 9EY4 - PubMed Abstract: 
Access to small, rigid, and sp3-rich molecules is a major limitation in the drug discovery for challenging protein targets. FK506-binding proteins hold high potential as drug targets or enablers of molecular glues but are fastidious in the chemotypes accepted as ligands. We here report an enantioselective synthesis of a highly rigidified pipecolate-mimicking tricyclic scaffold that precisely position functional groups for interacting with FKBPs. This was enabled by a 14-step gram-scale synthesis featuring anodic oxidation, stereospecific vinylation, and N-acyl iminium cyclization. Structure-based optimization resulted in the discovery of FKBP inhibitors with picomolar biochemical and subnanomolar cellular activity that represent the most potent FKBP ligands known to date.
Organizational Affiliation: 
Technische Universitat Darmstadt, Chemistry, GERMANY.