Secondary Sulfonamides as Effective Lactoperoxidase Inhibitors

Molecules. 2017 May 24;22(6):793. doi: 10.3390/molecules22060793.

Abstract

Secondary sulfonamides (4a-8h) incorporating acetoxybenzamide, triacetoxybenzamide, hydroxybenzamide, and trihydroxybenzamide and possessing thiazole, pyrimidine, pyridine, isoxazole and thiadiazole groups were synthesized. Lactoperoxidase (LPO, E.C.1.11.1.7), as a natural antibacterial agent, is a peroxidase enzyme secreted from salivary, mammary, and other mucosal glands. In the present study, the in vitro inhibitory effects of some secondary sulfonamide derivatives (4a-8h) were examined against LPO. The obtained results reveal that secondary sulfonamide derivatives (4a-8h) are effective LPO inhibitors. The Ki values of secondary sulfonamide derivatives (4a-8h) were found in the range of 1.096 × 10-3 to 1203.83 µM against LPO. However, the most effective inhibition was found for N-(sulfathiazole)-3,4,5-triacetoxybenzamide (6a), with Ki values of 1.096 × 10-3 ± 0.471 × 10-3 µM as non-competitive inhibition.

Keywords: enzyme inhibition; enzyme purification; lactoperoxidase; secondary sulfonamide.

MeSH terms

  • Anti-Bacterial Agents / chemistry*
  • Anti-Bacterial Agents / pharmacology*
  • Enzyme Inhibitors / chemistry*
  • Enzyme Inhibitors / pharmacology*
  • Isoxazoles / chemistry
  • Lactoperoxidase / antagonists & inhibitors*
  • Lactoperoxidase / metabolism*
  • Pyridines / chemistry
  • Pyrimidines / chemistry
  • Sulfonamides / chemistry*
  • Sulfonamides / pharmacology*
  • Thiadiazoles / chemistry

Substances

  • Anti-Bacterial Agents
  • Enzyme Inhibitors
  • Isoxazoles
  • Pyridines
  • Pyrimidines
  • Sulfonamides
  • Thiadiazoles
  • Lactoperoxidase
  • pyrimidine
  • pyridine