3WZJ

CRYSTAL STRUCTURE OF HUMAN MPS1 CATALYTIC DOMAIN IN COMPLEX WITH 4-(6-(cyclohexylamino)-8-(((tetrahydro-2H-pyran-4-yl)methyl)amino)imidazo[1,2-b]pyridazin-3-yl)-N-cyclopropylbenzamide


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.75 Å
  • R-Value Free: 0.282 
  • R-Value Work: 0.221 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Discovery of Imidazo[1,2-b]pyridazine Derivatives: Selective and Orally Available Mps1 (TTK) Kinase Inhibitors Exhibiting Remarkable Antiproliferative Activity

Kusakabe, K.I.Ide, N.Daigo, Y.Itoh, T.Yamamoto, T.Hashizume, H.Nozu, K.Yoshida, H.Tadano, G.Tagashira, S.Higashino, K.Okano, Y.Sato, Y.Inoue, M.Iguchi, M.Kanazawa, T.Ishioka, Y.Dohi, K.Kido, Y.Sakamoto, S.Ando, S.Maeda, M.Higaki, M.Baba, Y.Nakamura, Y.

(2015) J.Med.Chem. --: --

  • DOI: 10.1021/jm501599u
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Monopolar spindle 1 (Mps1) is an attractive oncology target due to its high expression level in cancer cells as well as the correlation of its expression levels with histological grades of cancers. An imidazo[1,2-a]pyrazine 10a was identified during ...

    Monopolar spindle 1 (Mps1) is an attractive oncology target due to its high expression level in cancer cells as well as the correlation of its expression levels with histological grades of cancers. An imidazo[1,2-a]pyrazine 10a was identified during an HTS campaign. Although 10a exhibited good biochemical activity, its moderate cellular as well as antiproliferative activities needed to be improved. The cocrystal structure of an analogue of 10a guided our lead optimization to introduce substituents at the 6-position of the scaffold, giving the 6-aryl substituted 21b which had improved cellular activity but no oral bioavailability in rat. Property-based optimization at the 6-position and a scaffold change led to the discovery of the imidazo[1,2-b]pyridazine-based 27f, an extremely potent (cellular Mps1 IC50 = 0.70 nM, A549 IC50 = 6.0 nM), selective Mps1 inhibitor over 192 kinases, which could be orally administered and was active in vivo. This 27f demonstrated remarkable antiproliferative activity in the nanomolar range against various tissue cancer cell lines.


    Organizational Affiliation

    Medicinal Research Laboratories, ‡Drug Developmental Research Laboratories, and §Innovative Drug Discovery Research Laboratories, Shionogi Pharmaceutical Research Center , 1-1 Futaba-cho 3-chome, Toyonaka, Osaka 561-0825, Japan.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Dual specificity protein kinase TTK
A
321Homo sapiensMutation(s): 0 
Gene Names: TTK (MPS1, MPS1L1)
EC: 2.7.12.1
Find proteins for P33981 (Homo sapiens)
Go to Gene View: TTK
Go to UniProtKB:  P33981
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
O43
Query on O43

Download SDF File 
Download CCD File 
A
4-{6-(cyclohexylamino)-8-[(tetrahydro-2H-pyran-4-ylmethyl)amino]imidazo[1,2-b]pyridazin-3-yl}-N-cyclopropylbenzamide
C28 H36 N6 O2
ZOSFYOBMRYUXAN-UHFFFAOYSA-N
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
O43IC50: 5.6 - 6.6 nM (100) BINDINGDB
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.75 Å
  • R-Value Free: 0.282 
  • R-Value Work: 0.221 
  • Space Group: I 2 2 2
Unit Cell:
Length (Å)Angle (°)
a = 70.961α = 90.00
b = 110.389β = 90.00
c = 114.356γ = 90.00
Software Package:
Software NamePurpose
HKL-2000data scaling
CrystalCleardata collection
REFMACrefinement
HKL-2000data reduction
MOLREPphasing
PDB_EXTRACTdata extraction
SCALEPACKdata scaling
DENZOdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Revision History 

  • Version 1.0: 2015-02-11
    Type: Initial release
  • Version 1.1: 2017-11-22
    Type: Refinement description