Aurora-A bound to an inhibitor

Experimental Data Snapshot

  • Resolution: 3.35 Å
  • R-Value Free: 0.299 
  • R-Value Work: 0.227 
  • R-Value Observed: 0.231 

wwPDB Validation   3D Report Full Report

Ligand Structure Quality Assessment 

This is version 1.4 of the entry. See complete history


Imidazo[4,5-b]pyridine derivatives as inhibitors of Aurora kinases: lead optimization studies toward the identification of an orally bioavailable preclinical development candidate.

Bavetsias, V.Large, J.M.Sun, C.Bouloc, N.Kosmopoulou, M.Matteucci, M.Wilsher, N.E.Martins, V.Reynisson, J.Atrash, B.Faisal, A.Urban, F.Valenti, M.de Haven Brandon, A.Box, G.Raynaud, F.I.Workman, P.Eccles, S.A.Bayliss, R.Blagg, J.Linardopoulos, S.McDonald, E.

(2010) J Med Chem 53: 5213-5228

  • DOI: https://doi.org/10.1021/jm100262j
  • Primary Citation of Related Structures:  
    2X6D, 2X6E

  • PubMed Abstract: 

    Lead optimization studies using 7 as the starting point led to a new class of imidazo[4,5-b]pyridine-based inhibitors of Aurora kinases that possessed the 1-benzylpiperazinyl motif at the 7-position, and displayed favorable in vitro properties. Cocrystallization of Aurora-A with 40c (CCT137444) provided a clear understanding into the interactions of this novel class of inhibitors with the Aurora kinases. Subsequent physicochemical property refinement by the incorporation of solubilizing groups led to the identification of 3-((4-(6-bromo-2-(4-(4-methylpiperazin-1-yl)phenyl)-3H-imidazo[4,5-b]pyridin-7-yl)piperazin-1-yl)methyl)-5-methylisoxazole (51, CCT137690) which is a potent inhibitor of Aurora kinases (Aurora-A IC(50) = 0.015 +/- 0.003 muM, Aurora-B IC(50) = 0.025 muM, Aurora-C IC(50) = 0.019 muM). Compound 51 is highly orally bioavailable, and in in vivo efficacy studies it inhibited the growth of SW620 colon carcinoma xenografts following oral administration with no observed toxicities as defined by body weight loss.

  • Organizational Affiliation

    Cancer Research UK Centre for Cancer Therapeutics, The Institute of Cancer Research, 15 Cotswold Road, Sutton, Surrey, SM2 5NG, United Kingdom. vassilios.bavetsias@icr.ac.uk

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
SERINE/THREONINE-PROTEIN KINASE 6285Homo sapiensMutation(s): 0 
UniProt & NIH Common Fund Data Resources
Find proteins for O14965 (Homo sapiens)
Explore O14965 
Go to UniProtKB:  O14965
PHAROS:  O14965
GTEx:  ENSG00000087586 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupO14965
Sequence Annotations
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
Query on YM4

Download Ideal Coordinates CCD File 
C26 H31 Br N8 O
Binding Affinity Annotations 
IDSourceBinding Affinity
YM4 BindingDB:  2X6E IC50: 15 (nM) from 1 assay(s)
PDBBind:  2X6E IC50: 15 (nM) from 1 assay(s)
Experimental Data & Validation

Experimental Data

  • Resolution: 3.35 Å
  • R-Value Free: 0.299 
  • R-Value Work: 0.227 
  • R-Value Observed: 0.231 
  • Space Group: P 61 2 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 83.25α = 90
b = 83.25β = 90
c = 163.31γ = 120
Software Package:
Software NamePurpose
MOSFLMdata reduction
SCALAdata scaling

Structure Validation

View Full Validation Report

Ligand Structure Quality Assessment 

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2010-07-07
    Type: Initial release
  • Version 1.1: 2011-05-08
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2018-02-28
    Changes: Database references
  • Version 1.4: 2023-12-20
    Changes: Data collection, Database references, Derived calculations, Other, Refinement description