4DFF

The SAR development of dihydroimidazoisoquinoline derivatives as phosphodiesterase 10A inhibitors for the treatment of schizophrenia

• PDB DOI: https://doi.org/10.2210/pdb4DFF/pdb

• Classification: HYDROLASE/HYDROLASE INHIBITOR
• Mutation(s): No 


• Deposited: 2012-01-23 Released: 2012-03-14 
• Deposition Author(s): Ho, G.D., Seganish, W.M., Bercovici, A., Tulshian, D., Greenlee, W.J., Van Rijn, R., Hruza, A., Xiao, L., Rindgen, D., Mullins, D., Guzzi, M., Zhang, X., Bleichardt, C., Hodgson, R.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.11 Å
• R-Value Free: 0.223 
• R-Value Work: 0.190 
• R-Value Observed: 0.192 

Literature

The SAR development of dihydroimidazoisoquinoline derivatives as phosphodiesterase 10A inhibitors for the treatment of schizophrenia.

Ho, G.D., Michael Seganish, W., Bercovici, A., Tulshian, D., Greenlee, W.J., Van Rijn, R., Hruza, A., Xiao, L., Rindgen, D., Mullins, D., Guzzi, M., Zhang, X., Bleickardt, C., Hodgson, R.

(2012) Bioorg Med Chem Lett 22: 2585-2589

• PubMed: 22377514 
• DOI: https://doi.org/10.1016/j.bmcl.2012.01.113
• Primary Citation of Related Structures:  
  4DFF


• PubMed Abstract: 
  

  The identification of potent and orally active dihydroimidazoisoquinolines as PDE 10A inhibitors is reported. The SAR development led to the discovery of compound 35 as a potent, selective, and orally active PDE10A inhibitor. Compound 35 inhibited MK-801-induced hyperactivity at 3mg/kg and displayed a 10-fold separation between the minimal effective doses for inhibition of MK-801-induced hyperactivity and hypolocomotion in rats.

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Organizational Affiliation: 

Department of Medicinal Chemistry, Merck Research Laboratories, Kenilworth, NJ 07033, 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: 81.49 kDa 
• Atom Count: 4,815 
• Modelled Residue Count: 584 
• Deposited Residue Count: 704 
• Unique protein chains: 1

Macromolecules

Small Molecules

Ligands 3 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
0JP	E [auth B]	8,9-dimethoxy-1-(1,3-thiazol-5-yl)-5,6-dihydroimidazo[5,1-a]isoquinoline C16 H15 N3 O2 S GFIAXSKRRKHJBD-UHFFFAOYSA-N
ZN	D [auth A], G [auth B]	ZINC ION Zn PTFCDOFLOPIGGS-UHFFFAOYSA-N
MG	C [auth A], F [auth B]	MAGNESIUM ION Mg JLVVSXFLKOJNIY-UHFFFAOYSA-N

Binding Affinity Annotations
ID	Source	Binding Affinity
0JP	PDBBind:  4DFF	Ki: 35 (nM) from 1 assay(s)
	BindingDB:  4DFF	Ki: 35 (nM) from 1 assay(s)

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.11 Å
• R-Value Free: 0.223 
• R-Value Work: 0.190 
• R-Value Observed: 0.192 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 48.654	α = 90
b = 81.177	β = 90
c = 153.323	γ = 90

Software Package:

Software Name	Purpose
BUSTER	refinement
HKL-2000	data reduction
HKL-2000	data scaling

Structure Validation

Entry History 

Deposition Data

• Released Date: 2012-03-14 
Deposition Author(s): Ho, G.D., Seganish, W.M., Bercovici, A., Tulshian, D., Greenlee, W.J., Van Rijn, R., Hruza, A., Xiao, L., Rindgen, D., Mullins, D., Guzzi, M., Zhang, X., Bleichardt, C., Hodgson, R.

Revision History  

• Version 1.0: 2012-03-14
  Type: Initial release
  
• Version 1.1: 2012-04-04
  Changes: Database references
• Version 1.2: 2024-10-30
  Changes: Data collection, Database references, Derived calculations, Structure summary