3IO7 | pdb_00003io7

2-Aminopyrazolo[1,5-a]pyrimidines as potent and selective inhibitors of JAK2

• PDB DOI: https://doi.org/10.2210/pdb3IO7/pdb

• Classification: TRANSFERASE
• Organism(s): Homo sapiens
• Expression System: unidentified baculovirus
• Mutation(s): No 


• Deposited: 2009-08-13 Released: 2009-11-10 
• Deposition Author(s): Zuccola, H.J., Ledeboer, M.W., Pierce, A.C.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.60 Å
• R-Value Free: 
  0.294 (Depositor), 0.287 (DCC) 
• R-Value Work: 
  0.199 (Depositor), 0.198 (DCC) 
• R-Value Observed: 
  0.206 (Depositor) 

Literature

2-Aminopyrazolo[1,5-a]pyrimidines as potent and selective inhibitors of JAK2.

Ledeboer, M.W., Pierce, A.C., Duffy, J.P., Gao, H., Messersmith, D., Salituro, F.G., Nanthakumar, S., Come, J., Zuccola, H.J., Swenson, L., Shlyakter, D., Mahajan, S., Hoock, T., Fan, B., Tsai, W.J., Kolaczkowski, E., Carrier, S., Hogan, J.K., Zessis, R., Pazhanisamy, S., Bennani, Y.L.

(2009) Bioorg Med Chem Lett 19: 6529-6533

• PubMed: 19857967 
• DOI: https://doi.org/10.1016/j.bmcl.2009.10.053
• Primary Citation Related Structures: 
  3IO7, 3IOK


• PubMed Abstract: 
  

  Constitutive activation of the EPO/JAK2 signaling cascade has recently been implicated in a variety of myeloproliferative disorders including polycythemia vera, essential thrombocythemia and myelofibrosis. In an effort to uncover therapeutic potential of blocking the EPO/JAK2 signaling cascade, we sought to discover selective inhibitors that block the kinase activity of JAK2. Herein, we describe the discovery and structure based optimization of a novel series of 2-amino-pyrazolo[1,5-a]pyrimidines that exhibit potent inhibition of JAK2.

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Organizational Affiliation: 
• Vertex Pharmaceuticals Inc, Cambridge, MA 02139-4242, 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)

Macromolecule Content 

• Total Structure Weight: 37.18 kDa 
• Atom Count: 2,427 
• Modeled Residue Count: 284 
• Deposited Residue Count: 313 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Tyrosine-protein kinase JAK2	A	313	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 GTEx:  ENSG00000096968

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
1P5	B [auth A]	(3S)-1-[6-(2-aminopyrazolo[1,5-a]pyrimidin-3-yl)pyrimidin-4-yl]-N,N-diethylpiperidine-3-carboxamide C20 H26 N8 O DKQKJWFBAJGEBC-AWEZNQCLSA-N

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

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.60 Å
• R-Value Free:  0.294 (Depositor), 0.287 (DCC) 
• R-Value Work:  0.199 (Depositor), 0.198 (DCC) 
• R-Value Observed: 0.206 (Depositor) 

Space Group: C 2 2 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 93.922	α = 90
b = 101.752	β = 90
c = 67.194	γ = 90

Software Package:

Software Name	Purpose
DENZO	data reduction
SCALEPACK	data scaling
REFMAC	refinement
PDB_EXTRACT	data extraction
BOS	data collection
HKL-2000	data scaling
REFMAC	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 2009-11-10 
Deposition Author(s): Zuccola, H.J., Ledeboer, M.W., Pierce, A.C.

Revision History  

• Version 1.0: 2009-11-10
  Type: Initial release
  
• Version 1.1: 2011-07-13
  Changes: Version format compliance
• Version 1.2: 2017-11-01
  Changes: Refinement description
• Version 1.3: 2024-03-13
  Changes: Data collection, Database references, Derived calculations, Source and taxonomy, Structure summary
• Version 1.4: 2024-11-06
  Changes: Structure summary