Discovery of a PCAF Bromodomain Chemical Probe.
Moustakim, M., Clark, P.G., Trulli, L., Fuentes de Arriba, A.L., Ehebauer, M.T., Chaikuad, A., Murphy, E.J., Mendez-Johnson, J., Daniels, D., Hou, C.D., Lin, Y.H., Walker, J.R., Hui, R., Yang, H., Dorrell, L., Rogers, C.M., Monteiro, O.P., Fedorov, O., Huber, K.V., Knapp, S., Heer, J., Dixon, D.J., Brennan, P.E.(2017) Angew Chem Int Ed Engl 56: 827-831
- PubMed: 27966810 
- DOI: https://doi.org/10.1002/anie.201610816
- Primary Citation of Related Structures:  
5TPX - PubMed Abstract: 
The p300/CBP-associated factor (PCAF) and related GCN5 bromodomain-containing lysine acetyl transferases are members of subfamily I of the bromodomain phylogenetic tree. Iterative cycles of rational inhibitor design and biophysical characterization led to the discovery of the triazolopthalazine-based L-45 (dubbed L-Moses) as the first potent, selective, and cell-active PCAF bromodomain (Brd) inhibitor. Synthesis from readily available (1R,2S)-(-)-norephedrine furnished L-45 in enantiopure form. L-45 was shown to disrupt PCAF-Brd histone H3.3 interaction in cells using a nanoBRET assay, and a co-crystal structure of L-45 with the homologous Brd PfGCN5 from Plasmodium falciparum rationalizes the high selectivity for PCAF and GCN5 bromodomains. Compound L-45 shows no observable cytotoxicity in peripheral blood mononuclear cells (PBMC), good cell-permeability, and metabolic stability in human and mouse liver microsomes, supporting its potential for in vivo use.
Organizational Affiliation: 
Structural Genomics Consortium & Target Discovery Institute, University of Oxford, NDM Research Building, Roosevelt Drive, Oxford, OX3 7DQ and OX3 7FZ, UK.