8OF2

Trypanosoma brucei pteridine reductase 1 (TbPTR1) in complex with 2,4,6 triamminopyrimidine (TAP)


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.48 Å
  • R-Value Free: 0.195 
  • R-Value Work: 0.162 
  • R-Value Observed: 0.164 

Starting Model: experimental
View more details

wwPDB Validation   3D Report Full Report


Ligand Structure Quality Assessment 


This is version 1.0 of the entry. See complete history


Literature

The discovery of aryl-2-nitroethyl triamino pyrimidines as anti-Trypanosoma brucei agents.

Linciano, P.Pozzi, C.Tassone, G.Landi, G.Mangani, S.Santucci, M.Luciani, R.Ferrari, S.Santarem, N.Tagliazucchi, L.Cordeiro-da-Silva, A.Tonelli, M.Tondi, D.Bertarini, L.Gul, S.Witt, G.Moraes, C.B.Costantino, L.Costi, M.P.

(2023) Eur J Med Chem 264: 115946-115946

  • DOI: https://doi.org/10.1016/j.ejmech.2023.115946
  • Primary Citation of Related Structures:  
    8OF2

  • PubMed Abstract: 

    Pteridine reductase 1 (PTR1) is a catalytic protein belonging to the folate metabolic pathway in Trypanosmatidic parasites. PTR1 is a known target for the medicinal chemistry development of antiparasitic agents against Trypanosomiasis and Leishmaniasis. In previous studies, new nitro derivatives were elaborated as PTR1 inhibitors. The compounds showing a diamino-pyrimidine core structure were previously developed but they showed limited efficacy. Therefore, a new class of phenyl-, heteroaryl- and benzyloxy-nitro derivatives based on the 2-nitroethyl-2,4,6-triaminopyrimidine scaffold were designed and tested. The compounds were assayed for their ability to inhibit T. brucei and L. major PTR1 enzymes and for their antiparasitic activity towards T. brucei and L. infantum parasites. To understand the structure-activity relationships of the compounds against TbPTR1, the X-ray crystallographic structure of the 2,4,6-triaminopyrimidine (TAP) was obtained and molecular modelling studies were performed. As a next step, only the most effective compounds against T. brucei were then tested against the amastigote cellular stage of T. cruzi, searching for a broad-spectrum antiprotozoal agent. An early ADME-Tox profile evaluation was performed. The early toxicity profile of this class of compounds was investigated by measuring their inhibition of hERG and five cytochrome P450 isoforms (CYP1A2, CYP2C9, CYP2C19, CYP2D6 and CYP3A4), cytotoxicity towards A549 cells and mitochondrial toxicity. Pharmacokinetic studies (SNAP-PK) were performed on selected compounds using hydroxypropyl-β-cyclodextrins (50 % w/v) to preliminarily study their plasma concentration when administered per os at a dose of 20 mg/kg. Compound 1p, showed the best pharmacodynamic and pharmacokinetic properties, can be considered a good candidate for further bioavailability and efficacy studies.


  • Organizational Affiliation

    Department of Life Sciences, University of Modena and Reggio Emilia, Via Campi 103, 41125, Modena, Italy.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Pteridine reductase
A, B, C, D
288Trypanosoma brucei bruceiMutation(s): 0 
Gene Names: PTR1
EC: 1.5.1.33
UniProt
Find proteins for Q581W1 (Trypanosoma brucei brucei (strain 927/4 GUTat10.1))
Explore Q581W1 
Go to UniProtKB:  Q581W1
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ581W1
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Ligands 4 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
NDP
Query on NDP

Download Ideal Coordinates CCD File 
F [auth A],
G [auth B],
J [auth C],
M [auth D]
NADPH DIHYDRO-NICOTINAMIDE-ADENINE-DINUCLEOTIDE PHOSPHATE
C21 H30 N7 O17 P3
ACFIXJIJDZMPPO-NNYOXOHSSA-N
3AY (Subject of Investigation/LOI)
Query on 3AY

Download Ideal Coordinates CCD File 
E [auth A],
H [auth B],
K [auth C],
N [auth D]
PYRIMIDINE-2,4,6-TRIAMINE
C4 H7 N5
JTTIOYHBNXDJOD-UHFFFAOYSA-N
EDO
Query on EDO

Download Ideal Coordinates CCD File 
I [auth B]1,2-ETHANEDIOL
C2 H6 O2
LYCAIKOWRPUZTN-UHFFFAOYSA-N
ACT
Query on ACT

Download Ideal Coordinates CCD File 
L [auth C],
O [auth D]
ACETATE ION
C2 H3 O2
QTBSBXVTEAMEQO-UHFFFAOYSA-M
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.48 Å
  • R-Value Free: 0.195 
  • R-Value Work: 0.162 
  • R-Value Observed: 0.164 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 74.77α = 90
b = 91.052β = 115.63
c = 83.027γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
XDSdata reduction
SCALAdata scaling
MOLREPphasing

Structure Validation

View Full Validation Report



Ligand Structure Quality Assessment 


Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
European Union (EU)European Union603240

Revision History  (Full details and data files)

  • Version 1.0: 2023-12-13
    Type: Initial release