4AQC

Triazolopyridine-based Inhibitor of Janus Kinase 2

• PDB DOI:  https://doi.org/10.2210/pdb4AQC/pdb

• Classification: TRANSFERASE
• Organism(s): Homo sapiens
• Expression System: Spodoptera frugiperda
• Mutation(s): No 


• Deposited: 2012-04-16 Released: 2012-04-25 
• Deposition Author(s): Dugan, B.J., Gingrich, D.E., Mesaros, E.F., Milkiewicz, K.L., Curry, M.A., Zulli, A.L., Dobrzanski, P., Serdikoff, C., Jan, M., Angeles, T.S., Albom, M.S., Mason, J.L., Aimone, L.D., Meyer, S.L., Huang, Z., Wells-Knecht, K.J., Ator, M.A., Ruggeri, B.A., Dorsey, B.D.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.90 Å
• R-Value Free: 0.217 
• R-Value Work: 0.176 
• R-Value Observed: 0.178 

Literature

A Selective, Orally Bioavailable 1,2,4-Triazolo[1,5-A]Pyridine-Based Inhibitor of Janus Kinase 2 for Use in Anticancer Therapy: Discovery of Cep-33779.

Dugan, B.J., Gingrich, D.E., Mesaros, E.F., Milkiewicz, K.L., Curry, M.A., Zulli, A.L., Dobrzanski, P., Serdikoff, C., Jan, M., Angeles, T.S., Albom, M.S., Mason, J.L., Aimone, L.D., Meyer, S.L., Huang, Z., Wells-Knecht, K.J., Ator, M.A., Ruggeri, B.A., Dorsey, B.D.

(2012) J Med Chem 55: 5243

• PubMed: 22594690 
• DOI: https://doi.org/10.1021/jm300248q
• Primary Citation of Related Structures:  
  4AQC


• PubMed Abstract: 
  

Members of the JAK family of nonreceptor tyrosine kinases play a critical role in the growth and progression of many cancers and in inflammatory diseases. JAK2 has emerged as a leading therapeutic target for oncology, providing a rationale for the development of a selective JAK2 inhibitor. A program to optimize selective JAK2 inhibitors to combat cancer while reducing the risk of immune suppression associated with JAK3 inhibition was undertaken. The structure-activity relationships and biological evaluation of a novel series of compounds based on a 1,2,4-triazolo[1,5-a]pyridine scaffold are reported. Para substitution on the aryl at the C8 position of the core was optimum for JAK2 potency (17). Substitution at the C2 nitrogen position was required for cell potency (21). Interestingly, meta substitution of C2-NH-aryl moiety provided exceptional selectivity for JAK2 over JAK3 (23). These efforts led to the discovery of CEP-33779 (29), a novel, selective, and orally bioavailable inhibitor of JAK2.

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Organizational Affiliation: 

Worldwide Discovery Research, Cephalon, Inc., 145 Brandywine Parkway, West Chester, Pennsylvania 19380, United States. [e-mail]

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors and generated by PISA (software)

Biological Assembly 2  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 2 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 72.29 kDa 
• Atom Count: 5,525 
• Modelled Residue Count: 588 
• Deposited Residue Count: 602 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
TYROSINE-PROTEIN KINASE JAK2	A, B	301	Homo sapiens	Mutation(s): 0  Gene Names: JAK2 EC: 2.7.10.2
UniProt & NIH Common Fund Data Resources
Find proteins for O60674 (Homo sapiens) Explore O60674  Go to UniProtKB:  O60674
PHAROS:  O60674

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
88A	C [auth A], E [auth B]	8-(4-methylsulfonylphenyl)-N-(4-morpholin-4-ylphenyl)-[1,2,4]triazolo[1,5-a]pyridin-2-amine C23 H23 N5 O3 S UUVZHZJBZYONMR-UHFFFAOYSA-N
SO4	D [auth A], F [auth B], G [auth B], H [auth B], I [auth B]	SULFATE ION O4 S QAOWNCQODCNURD-UHFFFAOYSA-L

Modified Residues  1 Unique
ID	Chains	Type	Formula	2D Diagram	Parent
PTR	A, B	L-PEPTIDE LINKING	C9 H12 N O6 P		TYR

Binding Affinity Annotations
ID	Source	Binding Affinity
88A	BindingDB:  4AQC	IC50: min: 0.9, max: 61 (nM) from 2 assay(s)
	PDBBind:  4AQC	IC50: 0.9 (nM) from 1 assay(s)
	Binding MOAD:  4AQC	IC50: 0.9 (nM) from 1 assay(s)

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.90 Å
• R-Value Free: 0.217 
• R-Value Work: 0.176 
• R-Value Observed: 0.178 
• Space Group: P 4₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 111.679	α = 90
b = 111.679	β = 90
c = 70.422	γ = 90

Software Package:

Software Name	Purpose
REFMAC	refinement
MOSFLM	data reduction
SCALA	data scaling

Structure Validation

Entry History 

Deposition Data

• Released Date: 2012-04-25 
Deposition Author(s): Dugan, B.J., Gingrich, D.E., Mesaros, E.F., Milkiewicz, K.L., Curry, M.A., Zulli, A.L., Dobrzanski, P., Serdikoff, C., Jan, M., Angeles, T.S., Albom, M.S., Mason, J.L., Aimone, L.D., Meyer, S.L., Huang, Z., Wells-Knecht, K.J., Ator, M.A., Ruggeri, B.A., Dorsey, B.D.

Revision History  

• Version 1.0: 2012-04-25
  Type: Initial release
  
• Version 1.1: 2012-06-27
  Changes: Other
• Version 1.2: 2019-05-08
  Changes: Data collection, Derived calculations, Experimental preparation, Other