Rational Design and Synthesis of Methyl-β-d-galactomalonyl Phenyl Esters as Potent Galectin-8 N Antagonists

J Med Chem. 2020 Oct 22;63(20):11573-11584. doi: 10.1021/acs.jmedchem.0c00602. Epub 2020 Oct 1.


Galectin-8 is a β-galactoside-recognizing protein having an important role in the regulation of bone remodeling and cancer progression and metastasis. Methyl β-d-galactopyranoside malonyl aromatic esters have been designed to target and engage with particular amino acid residues of the galectin-8N extended carbohydrate-binding site. The chemically synthesized compounds had in vitro binding affinity toward galectin-8N in the range of 5-33 μM, as evaluated by isothermal titration calorimetry. This affinity directly correlated with the compounds' ability to inhibit galectin-8-induced expression of chemokines and proinflammatory cytokines in the SUM159 breast cancer cell line. X-ray crystallographic structure determination revealed that these monosaccharide-based compounds bind galectin-8N by engaging its unique arginine (Arg59) and simultaneously cross-linking to another arginine (Arg45) located across the carbohydrate-binding site. This structure-based drug design approach has led to the discovery of novel monosaccharide galactose-based antagonists, with the strongest-binding compound (Kd 5.72 μM) holding 7-fold tighter than the disaccharide lactose.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Binding Sites
  • Cell Line, Tumor
  • Computer Simulation
  • Cytokines / genetics
  • Drug Design*
  • Female
  • Galactosides / chemical synthesis*
  • Galactosides / chemistry
  • Galactosides / pharmacology
  • Galectins / antagonists & inhibitors*
  • Humans
  • Molecular Docking Simulation
  • Molecular Structure
  • Protein Binding
  • Thermodynamics


  • Cytokines
  • Galactosides
  • Galectins
  • LGALS8 protein, human