Inducible nitric oxide synthase inhibitors: A comprehensive update

Area of Science:

• Biochemistry
• Pharmacology
• Medicinal Chemistry

Background:

• Inducible nitric oxide synthase (iNOS) produces nitric oxide (NO), which, while cytoprotective, is implicated in multifactorial diseases like Parkinson's and Alzheimer's.
• Overexpression of iNOS and subsequent elevated NO levels contribute to the pathophysiology of various inflammatory and neurodegenerative conditions.
• Selective iNOS inhibition presents a promising therapeutic strategy for these complex diseases.

Purpose of the Study:

• To comprehensively review and classify natural and synthetic inhibitors of inducible nitric oxide synthase (iNOS).
• To provide medicinal chemists with a detailed overview of iNOS inhibitors reported since 2002, aiding in the rational design of novel therapeutic agents.
• To highlight key structural features of potent iNOS inhibitors to guide future drug development.

Main Methods:

• Systematic review and classification of scientific literature on iNOS inhibitors published from 2002 onwards.
• Categorization of synthetic inhibitors into arginine and non-arginine analogs, with further subclassification of non-arginine analogs.
• Inclusion and analysis of structures of potent compounds to identify functional groups critical for iNOS inhibitory activity and selectivity.

Main Results:

• Over 200 research reports on iNOS inhibitor development have been published.
• Synthetic inhibitors are broadly classified into arginine and non-arginine analogs, with non-arginine analogs further divided into amidines, heterocyclics, fused cyclics, steroidal, and chalcone derivatives.
• Structures of potent compounds reveal important functional groups for iNOS inhibition and selectivity.

Conclusions:

• Selective iNOS inhibition is a viable therapeutic approach for complex diseases.
• A comprehensive understanding of existing iNOS inhibitors, including their structures and mechanisms, is essential for developing new drugs.
• This review serves as a valuable resource for medicinal chemists engaged in the rational design of novel and effective iNOS inhibitors.