β-Sulfonamido Functionalized Aspartate Analogues as Excitatory Amino Acid Transporter Inhibitors: Distinct Subtype Selectivity Profiles Arising from Subtle Structural Differences

J Med Chem. 2016 Oct 13;59(19):8771-8786. doi: 10.1021/acs.jmedchem.6b01066. Epub 2016 Sep 16.

Abstract

In this study inspired by previous work on 3-substituted Asp analogues, we designed and synthesized a total of 32 β-sulfonamide Asp analogues and characterized their pharmacological properties at the excitatory amino acid transporter subtypes EAAT1, EAAT2, and EAAT3. In addition to several potent EAAT inhibitors displaying IC50 values ∼1 μM at all three subtypes, this elaborate structure-activity relationship also identified analogues exhibiting distinct preferences or selectivities for specific transporter subtypes. Introduction of two fluorine atoms on the phenyl ring yielded analogue 4y that displayed an IC50 of 0.8 μM at EAAT1 with a 14- and 9-fold preference over EAAT2 and EAAT3, respectively. Conversely, the m-CF3-phenyl analogue 4r was a potent selective EAAT2-inhibitor (IC50 = 2.8 μM) exhibiting 30- and 50-fold selectivity over EAAT1 and EAAT3, respectively. In conclusion, even small structural differences in these β-sulfonamide Asp analogues provide analogues with diverse EAAT subtype selectivity profiles.

MeSH terms

  • Aspartic Acid / analogs & derivatives*
  • Aspartic Acid / pharmacology*
  • Biological Transport / drug effects
  • Excitatory Amino Acid Transporter 1 / antagonists & inhibitors*
  • Excitatory Amino Acid Transporter 1 / metabolism
  • Excitatory Amino Acid Transporter 2
  • Excitatory Amino Acid Transporter 3 / antagonists & inhibitors*
  • Excitatory Amino Acid Transporter 3 / metabolism
  • Glutamate Plasma Membrane Transport Proteins / antagonists & inhibitors*
  • Glutamate Plasma Membrane Transport Proteins / metabolism
  • HEK293 Cells
  • Humans
  • Sulfonamides / chemistry*
  • Sulfonamides / pharmacology*

Substances

  • Excitatory Amino Acid Transporter 1
  • Excitatory Amino Acid Transporter 2
  • Excitatory Amino Acid Transporter 3
  • Glutamate Plasma Membrane Transport Proteins
  • SLC1A1 protein, human
  • SLC1A2 protein, human
  • SLC1A3 protein, human
  • Sulfonamides
  • Aspartic Acid