Discovery and development of novel pyrimidine and pyrazolo/thieno-fused pyrimidine derivatives as potent and orally active inducible nitric oxide synthase dimerization inhibitor with efficacy for arthritis

Eur J Med Chem. 2021 Mar 5:213:113174. doi: 10.1016/j.ejmech.2021.113174. Epub 2021 Jan 20.

Abstract

In order to discover and develop drug-like anti-inflammatory agents against arthritis, based on "Hit" we found earlier and to overcome drawbacks of toxicity, twelve series of total 89 novel pyrimidine, pyrazolo[4,3-d]pyrimidine and thieno[3,2-d]pyrimidine derivatives were designed, synthesized and screened for their anti-inflammatory activity against NO and toxicity for normal liver cells (LO2). Relationships of balance toxicity and activity have been summarized through multi-steps, and title compounds 22o, 22l were found to show lower toxicity (against LO2: IC50 = 2934, 2301 μM, respectively) and potent effect against NO release (IR = 98.3, 97.67%, at 10 μM, respectively). Furthermore, compound 22o showed potent iNOS inhibitory activity with value of IC50 is 0.96 μM and could interfere stability and formation of the active dimeric iNOS. It's anti-inflammatory activity in vivo was assessed by AIA rat model. Furthermore, the results of metabolic stability, CYP, PK study in vivo, acute toxicity study and subacute toxicity assessment indicated this compound had good drug-like properties for treatment.

Keywords: Anti-inflammatory activity; Arthritis; Drug-like properties; Thieno[3,2-d]pyrimidine; iNOS inhibitory activity.

MeSH terms

  • Administration, Oral
  • Animals
  • Arthritis / drug therapy*
  • Arthritis / metabolism
  • Cells, Cultured
  • Dimerization
  • Disease Models, Animal
  • Dose-Response Relationship, Drug
  • Drug Development*
  • Enzyme Inhibitors / administration & dosage
  • Enzyme Inhibitors / chemistry
  • Enzyme Inhibitors / pharmacology*
  • Freund's Adjuvant
  • Humans
  • Lipopolysaccharides / antagonists & inhibitors
  • Lipopolysaccharides / pharmacology
  • Male
  • Mice
  • Molecular Structure
  • Nitric Oxide / antagonists & inhibitors
  • Nitric Oxide / biosynthesis
  • Nitric Oxide Synthase Type II / antagonists & inhibitors*
  • Nitric Oxide Synthase Type II / metabolism
  • Pyrazoles / administration & dosage
  • Pyrazoles / chemistry
  • Pyrazoles / pharmacology*
  • Pyrimidines / administration & dosage
  • Pyrimidines / chemistry
  • Pyrimidines / pharmacology*
  • RAW 264.7 Cells
  • Rats
  • Rats, Sprague-Dawley
  • Structure-Activity Relationship

Substances

  • Enzyme Inhibitors
  • Lipopolysaccharides
  • Pyrazoles
  • Pyrimidines
  • Nitric Oxide
  • pyrazole
  • Freund's Adjuvant
  • NOS2 protein, human
  • Nitric Oxide Synthase Type II
  • pyrimidine