2-Substituted 7-trifluoromethyl-thiadiazolopyrimidones as alkaline phosphatase inhibitors. Synthesis, structure activity relationship and molecular docking study

Eur J Med Chem. 2018 Jan 20:144:116-127. doi: 10.1016/j.ejmech.2017.11.068. Epub 2017 Dec 6.

Abstract

Alkaline Phosphatases (APs) play a key role in maintaining a ratio of phosphate to inorganic pyrophosphate (Pi/PPi) and thus regulate extracellular matrix calcification during bone formation and growth. Among different isozymes of AP, aberrant increase in the level of tissue non-specific alkaline phosphatase (TNAP) is strongly associated with vascular calcification and end-stage renal diseases. In this context, we synthesized a novel series of fluorinated pyrimidone derivatives, i.e., 2-bromo-7-trifluoromethyl-5-oxo-5H-1,3,4-thiadiazolepyrimidones. The bromine functionality was further used for derivatisation by nucleophilic aromatic substitution using amines as nucleophiles as well as by Palladium catalysed Suzuki-Miyaura reactions. The synthesized derivatives were found potent but non-selective inhibitors of both isozymes of AP. Arylated thiadiazolopyrimidones exhibited stronger inhibitory activities than 2-amino-thiadiazolopyrimidones. The binding modes and possible interactions of the most active inhibitor within the active site of the enzyme were observed by molecular docking studies.

Keywords: Alkaline Phosphatase (AP); Cross coupling reactions; Ectonucleotidases; Suzuki-Miyaura reaction; Thiadiazolopyrimidones.

MeSH terms

  • Alkaline Phosphatase / antagonists & inhibitors*
  • Alkaline Phosphatase / metabolism
  • Enzyme Inhibitors / chemical synthesis
  • Enzyme Inhibitors / chemistry*
  • Enzyme Inhibitors / pharmacology*
  • Halogenation
  • Humans
  • Molecular Docking Simulation
  • Pyrimidinones / chemical synthesis
  • Pyrimidinones / chemistry*
  • Pyrimidinones / pharmacology*
  • Structure-Activity Relationship
  • Thiadiazoles / chemical synthesis
  • Thiadiazoles / chemistry*
  • Thiadiazoles / pharmacology*

Substances

  • Enzyme Inhibitors
  • Pyrimidinones
  • Thiadiazoles
  • Alkaline Phosphatase