Experimental Data Snapshot

  • Resolution: 2.40 Å
  • R-Value Work: 0.159 
  • R-Value Observed: 0.159 

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Structure-based inhibitors of influenza virus sialidase. A benzoic acid lead with novel interaction.

Singh, S.Jedrzejas, M.J.Air, G.M.Luo, M.Laver, W.G.Brouillette, W.J.

(1995) J Med Chem 38: 3217-3225

  • DOI: https://doi.org/10.1021/jm00017a005
  • Primary Citation of Related Structures:  
    1INF, 1ING, 1INH

  • PubMed Abstract: 

    Influenza virus sialidase is a surface enzyme that is essential for infection of the virus. The catalytic site is highly conserved among all known influenza variants, suggesting that this protein is a suitable target for drug intervention. The most potent known inhibitors are analogs of 2-deoxy-2,3-didehydro-N-acetylneuraminic acid (Neu5Ac2en), particularly the 4-guanidino derivative (4-guanidino-Neu5Ac2en). We utilized the benzene ring of 4-(N-acetylamino)benzoic acids as a cyclic template to substitute for the dihydropyran ring of Neu5Ac2en. In this study several 3-(N-acylamino) derivatives were prepared as potential replacements for the glycerol side chain of Neu5Ac2en, and some were found to interact with the same binding subsite of sialidase. Of greater significance was the observation that the 3-guanidinobenzoic acid derivative (equivalent to the 4-guanidino grouping of 4-guanidino-Neu5Ac2en), the most potent benzoic acid inhibitor of influenza sialidase thus far identified (IC50 = 10 microM), occupied the glycerol-binding subsite on sialidase as opposed to the guanidino-binding subsite. This benzoic acid derivative thus provides a new compound that interacts in a novel manner with the catalytic site of influenza sialidase.

  • Organizational Affiliation

    Department of Chemistry, University of Alabama at Birmingham 35294, USA.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
INFLUENZA VIRUS B/LEE/40 NEURAMINIDASE390Influenza B virusMutation(s): 0 
Find proteins for P03474 (Influenza B virus (strain B/Lee/1940))
Explore P03474 
Go to UniProtKB:  P03474
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP03474
Sequence Annotations
  • Reference Sequence
Small Molecules
Binding Affinity Annotations 
IDSourceBinding Affinity
ST4 Binding MOAD:  1INF IC50: 1.00e+4 (nM) from 1 assay(s)
PDBBind:  1INF IC50: 1.00e+4 (nM) from 1 assay(s)
Experimental Data & Validation

Experimental Data

  • Resolution: 2.40 Å
  • R-Value Work: 0.159 
  • R-Value Observed: 0.159 
  • Space Group: P 4 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 124.25α = 90
b = 124.25β = 90
c = 71.35γ = 90
Software Package:
Software NamePurpose
XENGENdata collection
X-PLORmodel building
XENGENdata reduction

Structure Validation

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Ligand Structure Quality Assessment 

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 1996-08-17
    Type: Initial release
  • Version 1.1: 2008-03-24
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Derived calculations, Version format compliance
  • Version 2.0: 2020-07-29
    Type: Remediation
    Reason: Carbohydrate remediation
    Changes: Atomic model, Data collection, Derived calculations, Other, Structure summary