Bioactive imidamide-based compounds targeted against nitric oxide synthase.

Area of Science:

• Medicinal Chemistry
• Pharmacology
• Immunology

Background:

• Inducible nitric oxide synthase (iNOS) plays a crucial role in inflammatory responses and diseases such as septic shock.
• Selective iNOS inhibition is a therapeutic strategy for managing immune-mediated inflammatory conditions.

Purpose of the Study:

• To design, synthesize, and evaluate novel pyridinyl-imidamide derivatives as selective iNOS inhibitors.
• To identify potent compounds with potential therapeutic applications in inflammatory diseases.

Main Methods:

• Synthesis of twelve substituted pyridinyl-imidamide derivatives.
• In vitro biological evaluation of NOS inhibitory activity.
• Pharmacological assays in rat aortic tissue.
• In silico analysis including drug-likeness and docking studies.

Main Results:

• Compound 9a, N-(3-hydroxy-3-(pyridin-3-yl)propyl)acetimidamide, exhibited potent and selective inhibition of iNOS (IC50 = 4.6 µM).
• Pharmacological assays confirmed iNOS inhibition and revealed no adverse cardiovascular effects for compound 9a.
• In silico studies predicted favorable drug-likeness and adequate cell viability for promising derivatives (9a, 9b, 9e, 9g).
• Docking studies suggested a specific binding mode for 9a involving Glu377, explaining its selectivity.

Conclusions:

• The synthesized pyridinyl-imidamide derivatives represent a promising class of iNOS inhibitors.
• Compound 9a is a potent and selective iNOS inhibitor with a good safety profile, suitable for further investigation in inflammatory conditions.
• The study also highlights an efficient synthetic route for pyridinyl-pyrimidine derivatives.