4WIV

Crystal Structure of the first bromodomain of human BRD4 in complex with a novel inhibitor UMB32 (N-TERT-BUTYL-2-[4-(3,5-DIMETHYL-1,2-OXAZOL-4-YL) PHENYL]IMIDAZO[1,2-A]PYRAZIN-3-AMINE)

Summary for 4WIV

• Entry DOI: 10.2210/pdb4wiv/pdb
• Descriptor: Bromodomain-containing protein 4, N-tert-butyl-2-[4-(3,5-dimethyl-1,2-oxazol-4-yl)phenyl]imidazo[1,2-a]pyrazin-3-amine, 1,2-ETHANEDIOL, ... (5 entities in total)
• Functional Keywords: drug discovery, epigenesis, structure-activity relationship, tumor, transcription-transcription inhibitor complex, transcription/transcription inhibitor
• Biological source: Homo sapiens (Human)
• Cellular location: Nucleus: O60885
• Total number of polymer chains: 1
• Total formula weight: 15769.14

Authors

Xu, X.,Blacklow, S. (deposition date: 2014-09-26, release date: 2014-10-29, Last modification date: 2023-09-27)

Primary citation

McKeown, M.R.,Shaw, D.L.,Fu, H.,Liu, S.,Xu, X.,Marineau, J.J.,Huang, Y.,Zhang, X.,Buckley, D.L.,Kadam, A.,Zhang, Z.,Blacklow, S.C.,Qi, J.,Zhang, W.,Bradner, J.E.
Biased multicomponent reactions to develop novel bromodomain inhibitors.
J.Med.Chem., 57:9019-9027, 2014

PubMed Abstract: BET bromodomain inhibition has contributed new insights into gene regulation and emerged as a promising therapeutic strategy in cancer. Structural analogy of early methyl-triazolo BET inhibitors has prompted a need for structurally dissimilar ligands as probes of bromodomain function. Using fluorous-tagged multicomponent reactions, we developed a focused chemical library of bromodomain inhibitors around a 3,5-dimethylisoxazole biasing element with micromolar biochemical IC50. Iterative synthesis and biochemical assessment allowed optimization of novel BET bromodomain inhibitors based on an imidazo[1,2-a]pyrazine scaffold. Lead compound 32 (UMB-32) binds BRD4 with a Kd of 550 nM and 724 nM cellular potency in BRD4-dependent lines. Additionally, compound 32 shows potency against TAF1, a bromodomain-containing transcription factor previously unapproached by discovery chemistry. Compound 32 was cocrystallized with BRD4, yielding a 1.56 Å resolution crystal structure. This research showcases new applications of fluorous and multicomponent chemical synthesis for the development of novel epigenetic inhibitors.

PubMed: 25314271
DOI: 10.1021/jm501120z

Experimental method

X-RAY DIFFRACTION (1.56 Å)