New 4-(Morpholin-4-Yl)-3-Nitrobenzhydrazide Based Scaffold: Synthesis, Structural Insights, and Biological Evaluation
Michał Janowski1, Sara Janowska2, Sylwia Andrzejczuk3
1Medical University of Lublin, Doctoral School, 7 Chodzki Str., 20-093 Lublin, Poland.
Molecules (Basel, Switzerland)
|August 28, 2025
Summary
Researchers explored novel semicarbazides, thiosemicarbazides, and hydrazones to combat rising antimicrobial resistance. Semicarbazide derivatives showed the most promise, with one compound demonstrating significant antibacterial activity against Enterococcus faecalis.
Area of Science:
- Medicinal Chemistry
- Drug Discovery
- Antimicrobial Research
Background:
- Increasing antimicrobial resistance poses a global health challenge.
- Novel chemical scaffolds are needed to overcome existing drug resistance.
- Semicarbazides, thiosemicarbazides, and hydrazones are explored for antibiotic potential.
Purpose of the Study:
- To design and synthesize novel semicarbazide, thiosemicarbazide, and hydrazone derivatives.
- To evaluate the in vitro antimicrobial activity of these compounds against Gram-positive and Gram-negative bacteria.
- To identify new chemical structures with antibiotic properties distinct from current antibiotics.
Main Methods:
- Synthesis of novel semicarbazide, thiosemicarbazide, and hydrazone derivatives based on 4-(morpholino-4-yl)-3-nitrobenzohydrazide.
- In vitro antimicrobial assays against reference bacterial strains.
- Structure confirmation using single-crystal X-ray analysis and quantum chemical calculations.
Main Results:
- Semicarbazide derivatives exhibited the highest antimicrobial activity.
- A semicarbazide derivative with a 4-bromophenyl moiety showed potent activity against Enterococcus faecalis (MIC = 3.91 µg/mL).
- A thiosemicarbazide derivative with a 4-trifluoromethylphenyl group displayed moderate activity against Gram-positive bacteria (MIC = 31.25–62.5 µg/mL).
- Hydrazone derivatives showed no significant antimicrobial activity.
Conclusions:
- Novel semicarbazide derivatives show significant potential as antimicrobial agents.
- The 4-bromophenyl substituted semicarbazide is a promising lead compound for further development against Enterococcus faecalis.
- Further research into thiosemicarbazide derivatives may yield additional antimicrobial leads.
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