1BOZ

STRUCTURE-BASED DESIGN AND SYNTHESIS OF LIPOPHILIC 2,4-DIAMINO-6-SUBSTITUTED QUINAZOLINES AND THEIR EVALUATION AS INHIBITORS OF DIHYDROFOLATE REDUCTASE AND POTENTIAL ANTITUMOR AGENTS


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.1 Å
  • R-Value Work: 0.202 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Structure-based design and synthesis of lipophilic 2,4-diamino-6-substituted quinazolines and their evaluation as inhibitors of dihydrofolate reductases and potential antitumor agents.

Gangjee, A.Vidwans, A.P.Vasudevan, A.Queener, S.F.Kisliuk, R.L.Cody, V.Li, R.Galitsky, N.Luft, J.R.Pangborn, W.

(1998) J.Med.Chem. 41: 3426-3434

  • DOI: 10.1021/jm980081y

  • PubMed Abstract: 
  • The synthesis and biological activities of 14 6-substituted 2,4-diaminoquinazolines are reported. These compounds were designed to improve the cell penetration of a previously reported series of 2,4-diamino-6-substituted-pyrido[2,3-d]pyrimidines whic ...

    The synthesis and biological activities of 14 6-substituted 2,4-diaminoquinazolines are reported. These compounds were designed to improve the cell penetration of a previously reported series of 2,4-diamino-6-substituted-pyrido[2,3-d]pyrimidines which had shown significant potency and remarkable selectivity for Toxoplasma gondii dihydrofolate reductase (DHFR), but had much lower inhibitory effects on the growth of T. gondii cells in culture. The target N9-H analogues were obtained via regiospecific reductive amination of the appropriate benzaldehydes with 2,4,6-triaminoquinazoline, which, in turn, was synthesized from 2,4-diamino-6-nitroquinazoline. The N9-CH3 analogues were synthesized via a regiospecific reductive methylation of the corresponding N9-H precursors. The compounds were evaluated as inhibitors of DHFR from human, Pneumocystis carinii, T. gondii, rat liver, Lactobacillus casei, and Escherichia coli, and selected analogues were evaluated as inhibitors of the growth of tumor cells in culture. These analogues displayed potent T. gondii DHFR inhibition as well as inhibition of the growth of T. gondii cells in culture. Further, selected analogues were potent inhibitors of the growth of tumor cells in culture in the in vitro screening program of the National Cancer Institute with GI50s in the nanomolar and subnanomolar range. Crystallographic data for the ternary complex of hDHFR-NADPH and 2,4-diamino-6-[N-(2', 5'-dimethoxybenzyl)-N-methylamino]pyrido[2,3-d]pyrimidine, 1c, reveal the first structural details for a reversed N9-C10 folate bridge geometry as well as the first conformational details of a hybrid piritrexim-trimetrexate analogue.


    Related Citations: 
    • Comparison of Ternary Complexes of Pneumocystis carinii and Wild-Type Human Dihydrofolate Reductase With a Novel Classical Antitumor Furo[2,3-d]pyrimidine Antifolate
      Cody, V.,Galitsky, N.,Luft, J.R.,Pangborn, W.,Gangjee, A.,Devraj, R.,Queener, S.F.,Blakley, R.L.
      (1997) Acta Crystallogr.,Sect.D 53: 638
    • Comparison of Two Independent Crystal Structures of Human Dihydrofolate Reductase Ternary Complexes Reduced with Nicotinamide Adenine Dinucleotide Phosphate and the Very Tight-Binding Inhibitor Pt523
      Cody, V.,Galitsky, N.,Luft, J.R.,Pangborn, W.,Rosowsky, A.,Blakley, R.L.
      (1997) Biochemistry 36: 13897


    Organizational Affiliation

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




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
PROTEIN (DIHYDROFOLATE REDUCTASE)
A
186Homo sapiensGene 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 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PRD
Query on PRD

Download SDF File 
Download CCD File 
A
N6-(2,5-DIMETHOXY-BENZYL)-N6-METHYL-PYRIDO[2,3-D]PYRIMIDINE-2,4,6-TRIAMINE
C17 H20 N6 O2
HZTFNSCZLJLPEO-UHFFFAOYSA-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 %)
PRDIC50: 28 - 8500 nM (99) BINDINGDB
PRDIC50: 8500 nM BINDINGMOAD
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.1 Å
  • R-Value Work: 0.202 
  • Space Group: H 3
Unit Cell:
Length (Å)Angle (°)
a = 86.259α = 90.00
b = 86.259β = 90.00
c = 77.637γ = 120.00
Software Package:
Software NamePurpose
PROLSQrefinement
SCALEPACKdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1998-08-12
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance
  • Version 1.3: 2017-10-04
    Type: Refinement description