Indole-Pyrazole Hybrids: Synthesis, Structure, and Assessment of Their Hemolytic and Cytoprotective Properties
Karolina Babijczuk1, Klaudia Wawrzyniak1, Beata Warżajtis2
1Department of Bioactive Products, Faculty of Chemistry, Adam Mickiewicz University, Uniwersytetu Poznańskiego 8, 61-614 Poznan, Poland.
International Journal of Molecular Sciences
|September 27, 2025
Summary
Researchers created novel indole-pyrazole hybrid molecules. These compounds demonstrated significant cytoprotective effects on human erythrocytes under oxidative stress, with most showing no hemolytic activity.
Area of Science:
- Medicinal Chemistry
- Organic Synthesis
- Molecular Hybridization
Background:
- Molecular hybridization is a growing area of interest, combining diverse chemical and pharmacological fragments into single molecules.
- Indole and pyrazole scaffolds are prevalent in pharmacologically active compounds.
Purpose of the Study:
- To design and synthesize novel indole-pyrazole hybrids.
- To investigate the tautomer-selective reactions of these hybrids.
- To evaluate their in vitro hemolytic and cytoprotective properties.
Main Methods:
- Synthesis of indole-pyrazole hybrids with varied pyrazole ring substitutions.
- Characterization using spectroscopic methods and X-ray crystallography.
- In silico studies for physicochemical parameters and enzyme affinity estimation.
- In vitro evaluation of hemolytic and cytoprotective activity on human erythrocytes.
Main Results:
- Successful synthesis and characterization of indole-pyrazole hybrids.
- Demonstrated tautomer-selective reactions, with isolable tautomers depending on the bromo-methyl-pyrazole derivative used.
- In silico analysis provided key physicochemical parameters.
- In vitro studies revealed significant cytoprotective effects against oxidative stress in human erythrocytes.
- Most synthesized compounds exhibited no hemolytic activity.
Conclusions:
- Novel indole-pyrazole hybrids were synthesized and characterized.
- The study elucidated tautomer-selective reaction pathways.
- The synthesized hybrids show promise as cytoprotective agents with a favorable safety profile (lack of hemolytic activity).
Keywords:
cytoprotective propertiesgraminehuman erythrocytesindole derivativestautomer-selective reactionMore Related Videos
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