3NU0

Design, Synthesis, Biological Evaluation and X-ray Crystal Structure of Novel Classical 6,5,6-TricyclicBenzo[4,5]thieno[2,3-d]pyrimidines as Dual Thymidylate Synthase and Dihydrofolate Reductase Inhibitors

Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.35 Å
  • R-Value Free: 0.209 
  • R-Value Work: 0.180 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history. 

Literature

Design, synthesis, biological evaluation and X-ray crystal structure of novel classical 6,5,6-tricyclic benzo[4,5]thieno[2,3-d]pyrimidines as dual thymidylate synthase and dihydrofolate reductase inhibitors.

Zhang, X., Zhou, X., Kisliuk, R.L., Piraino, J., Cody, V., Gangjee, A.

(2011) Bioorg.Med.Chem. 19: 3585-3594

  • DOI: 10.1016/j.bmc.2011.03.067
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 

    • Classical antifolates (4-7) with a tricyclic benzo[4,5]thieno[2,3-d]pyrimidine scaffold and a flexible and rigid benzoylglutamate were synthesized as dual thymidylate synthase (TS) and dihydrofolate reductase (DHFR) inhibitors. Oxidative aromatizatio ...

    Classical antifolates (4-7) with a tricyclic benzo[4,5]thieno[2,3-d]pyrimidine scaffold and a flexible and rigid benzoylglutamate were synthesized as dual thymidylate synthase (TS) and dihydrofolate reductase (DHFR) inhibitors. Oxidative aromatization of ethyl 2-amino-4-methyl-4,5,6,7-tetrahydro-1-benzothiophene-3-carboxylate (±)-9 to ethyl 2-amino-4-methyl-1-benzothiophene-3-carboxylate 10 with 10% Pd/C was a key synthetic step. Compounds with 2-CH₃ substituents inhibited human (h) TS (IC₅₀ =0.26-0.8 μM), but not hDHFR. Substitution of the 2-CH₃ with a 2-NH₂ increases hTS inhibition by more than 10-fold and also affords excellent hDHFR inhibition (IC₅₀ = 0.09-0.1 μM). This study shows that the tricyclic benzo[4,5]thieno[2,3-d]pyrimidine scaffold is highly conducive to single hTS or dual hTS-hDHFR inhibition depending on the 2-position substituents. The X-ray crystal structures of 6 and 7 with hDHFR reveal, for the first time, that tricyclics 6 and 7 bind with the benzo[4,5]thieno[2,3-d]pyrimidine ring in the folate binding mode with the thieno S mimicking the 4-amino of methotrexate.

    Organizational Affiliation: 

    Division of Medicinal Chemistry, Graduate School of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA 15282, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Dihydrofolate reducatase
A
186Homo sapiensMutation(s): 0 
Gene Names: DHFR
EC: 1.5.1.3
Find proteins for P00374 (Homo sapiens)
Go to Gene View: DHFR
Go to UniProtKB:  P00374
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4
Download SDF File 
Download CCD File 
A
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
3TU
Query on 3TU
Download SDF File 
Download CCD File 
A
(2S)-2-(5-{[(2-amino-4-oxo-3,4-dihydro[1]benzothieno[2,3-d]pyrimidin-5-yl)methyl]amino}-1-oxo-1,3-dihydro-2H-isoindol-2-yl)pentanedioic acid
C24 H21 N5 O6 S
QPDXRVRRCIFNSL-HNNXBMFYSA-N
 Ligand Interaction
NDP
Query on NDP
Download SDF File 
Download CCD File 
A
NADPH DIHYDRO-NICOTINAMIDE-ADENINE-DINUCLEOTIDE PHOSPHATE
C21 H30 N7 O17 P3
ACFIXJIJDZMPPO-NNYOXOHSSA-N
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
3TUIC50: 100 nM (100) BINDINGDB
3TUIC50: 100 nM BINDINGMOAD
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.35 Å
  • R-Value Free: 0.209 
  • R-Value Work: 0.180 
  • Space Group: H 3
Unit Cell:
Length (Å)Angle (°)
a = 84.395α = 90.00
b = 84.395β = 90.00
c = 78.193γ = 120.00
Software Package:
Software NamePurpose
SCALAdata scaling
MOLREPphasing
MOSFLMdata reduction
REFMACrefinement
HKL-2000data collection

Structure Validation

View Full Validation Report or Ramachandran Plots


View more in-depth experimental data

Entry History 

Deposition Data

  • Deposited Date: 2010-07-06 
  • Released Date: 2011-05-25 
  • Deposition Author(s): Cody, V.

Revision History 

  • Version 1.0: 2011-05-25
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance
  • Version 1.2: 2017-11-08
    Type: Refinement description