4RIO

Crystal structure of JAK3 kinase domain in complex with a pyrrolopyridazine carboxamide inhibitor


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.69 Å
  • R-Value Free: 0.281 
  • R-Value Work: 0.215 
  • R-Value Observed: 0.218 

wwPDB Validation   3D Report Full Report


Ligand Structure Quality Assessment 


This is version 1.1 of the entry. See complete history


Literature

Discovery of pyrrolo[1,2-b]pyridazine-3-carboxamides as Janus kinase (JAK) inhibitors.

Duan, J.J.Lu, Z.Jiang, B.Yang, B.V.Doweyko, L.M.Nirschl, D.S.Haque, L.E.Lin, S.Brown, G.Hynes, J.Tokarski, J.S.Sack, J.S.Khan, J.Lippy, J.S.Zhang, R.F.Pitt, S.Shen, G.Pitts, W.J.Carter, P.H.Barrish, J.C.Nadler, S.G.Salter-Cid, L.M.McKinnon, M.Fura, A.Schieven, G.L.Wrobleski, S.T.

(2014) Bioorg Med Chem Lett 24: 5721-5726

  • DOI: https://doi.org/10.1016/j.bmcl.2014.10.061
  • Primary Citation of Related Structures:  
    4RIO

  • PubMed Abstract: 

    A new class of Janus kinase (JAK) inhibitors was discovered using a rationally designed pyrrolo[1,2-b]pyridazine-3-carboxamide scaffold. Preliminary studies identified (R)-(2,2-dimethylcyclopentyl)amine as a preferred C4 substituent on the pyrrolopyridazine core (3b). Incorporation of amino group to 3-position of the cyclopentane ring resulted in a series of JAK3 inhibitors (4g-4j) that potently inhibited IFNγ production in an IL2-induced whole blood assay and displayed high functional selectivity for JAK3-JAK1 pathway relative to JAK2. Further modifications led to the discovery of an orally bioavailable (2-fluoro-2-methylcyclopentyl)amino analogue 5g which is a nanomolar inhibitor of both JAK3 and TYK2, functionally selective for the JAK3-JAK1 pathway versus JAK2, and active in a human whole blood assay.


  • Organizational Affiliation

    Research and Development, Bristol-Myers Squibb Company, Princeton, NJ 08543-4000, USA. Electronic address: james.duan@bms.com.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Tyrosine-protein kinase JAK3293Homo sapiensMutation(s): 3 
Gene Names: JAK3
EC: 2.7.10.2
UniProt & NIH Common Fund Data Resources
Find proteins for P52333 (Homo sapiens)
Explore P52333 
Go to UniProtKB:  P52333
PHAROS:  P52333
GTEx:  ENSG00000105639 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP52333
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
3QX
Query on 3QX

Download Ideal Coordinates CCD File 
B [auth A]4-{[(1R,2S)-2-fluoro-2-methylcyclopentyl]amino}pyrrolo[1,2-b]pyridazine-3-carboxamide
C14 H17 F N4 O
UPBRYBJZTWHUQK-RISCZKNCSA-N
Binding Affinity Annotations 
IDSourceBinding Affinity
3QX BindingDB:  4RIO IC50: 1 (nM) from 1 assay(s)
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.69 Å
  • R-Value Free: 0.281 
  • R-Value Work: 0.215 
  • R-Value Observed: 0.218 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 47.54α = 90
b = 75.44β = 90
c = 87.98γ = 90
Software Package:
Software NamePurpose
BUSTERrefinement
HKL-2000data reduction
HKL-2000data scaling

Structure Validation

View Full Validation Report



Ligand Structure Quality Assessment 


Entry History 

Deposition Data

  • Released Date: 2014-12-24 
  • Deposition Author(s): Sack, J.S.

Revision History  (Full details and data files)

  • Version 1.0: 2014-12-24
    Type: Initial release
  • Version 1.1: 2024-02-28
    Changes: Data collection, Database references, Derived calculations