# The Antimicrobial and Cytotoxicity Properties of New Dibrominated 1,3-Dithiolium Flavonoids

**Authors:** Laura Gabriela Sarbu, Ana Alexandra Dumitru, Mihaela Savu, Isabela Andreea Sandu, Lucian Gabriel Bahrin, Marius Stefan, Mihail Lucian Birsa

PMC · DOI: 10.3390/ph19020259 · 2026-02-02

## TL;DR

Scientists created new flavonoids that strongly fight antibiotic-resistant bacteria like Staphylococcus aureus and Acinetobacter baumannii.

## Contribution

The study introduces novel dibrominated tricyclic flavonoids with superior antimicrobial efficacy against WHO priority pathogens.

## Key findings

- The new flavonoids showed strong antimicrobial activity against S. aureus, A. baumannii, and E. coli.
- MIC and MBC values against S. aureus were as low as 0.12 µg/mL and 1.9 µg/mL.
- The compounds outperformed natural flavonoids and conventional antibiotics in efficacy.

## Abstract

Background/Objectives: Antimicrobial resistance (AMR) presents a medical risk as well as a significant global socioeconomic challenge. Key contributors to AMR include the excessive use and incorrect application of antibiotics in humans and agriculture, nosocomial infections, and the absence of new classes of antibiotics. Methods: Novel dibrominated tricyclic flavonoids have been synthesized from the corresponding 3-dithiocarbamic flavanones and their antimicrobial and cytotoxicity properties have been investigated. Results: It has been found that these tricyclic flavonoids exhibit strong antimicrobial properties against clinically relevant pathogens such as Staphylococcus aureus, Acinetobacter baumannii, and Escherichia coli with MIC and MBC values against S. aureus ATCC 25923 as low as 0.12 µg/mL and 1.9 µg/mL, respectively. Conclusions: The synthetic tricyclic flavonoids exhibit strong antibacterial activity against selected WHO priority pathogens, including Staphylococcus aureus and Acinetobacter baumannii, surpassing the efficacy of both natural and synthetic flavonoids and several conventional antibiotics.

## Linked entities

- **Species:** Staphylococcus aureus (taxon 1280), Acinetobacter baumannii (taxon 470), Escherichia coli (taxon 562)

## Full-text entities

- **Diseases:** AMR (MESH:D060467), cancer (MESH:D009369), injury to (MESH:D014947), infectious diseases (MESH:D003141), MRSA (MESH:D013203), heart diseases (MESH:D006331), bacterial infections (MESH:D001424), Cytotoxicity (MESH:D064420), infections (MESH:D007239), deaths (MESH:D003643), nosocomial infections (MESH:D003428)
- **Chemicals:** 13C (MESH:C000615229), methicillin (MESH:D008712), ethanol (MESH:D000431), Panduratin A (MESH:C482884), kanamycin (MESH:D007612), erythromycin (MESH:D004917), moxifloxacin (MESH:D000077266), tetrafluoroborate (MESH:C098759), gentamicin (MESH:D005839), acetic acid (MESH:D019342), norwogonin (MESH:C055505), ceftazidime (MESH:D002442), clindamycin (MESH:D002981), kaempferol (MESH:C006552), water (MESH:D014867), C (MESH:D002244), flavonols (MESH:D044948), agar (MESH:D000362), quercetin (MESH:D011794), nitrogen (MESH:D009584), MHA (MESH:C069357), 3H (MESH:D014316), chalcones (MESH:D047188), flavanone (MESH:C028610), cefoxitin (MESH:D002440), sulfuric acid (MESH:C033158), benzaldehydes (MESH:D001547), Flavonoids (MESH:D005419), DMSO (MESH:D004121), chloramphenicol (MESH:D002701), H (MESH:D006859), sodium N,N-diethyldithiocarbamate (MESH:D004050), flavones (MESH:D047309), isobavachalcone (MESH:C468754), CHCl3 (MESH:D002725), benzopyran (MESH:D001578), diphenyl ether (MESH:C031538), CO2 (MESH:D002245), ampicillin (MESH:D000667), resazurin (MESH:C005843), TMS (MESH:D013932), acetone (MESH:D000096), lefamulin (MESH:C000591018), Flavanones (MESH:D044950), penicillin (MESH:D010406), glycerol (MESH:D005990), tetracycline (MESH:D013752), vaborbactam (MESH:C000626994), cefotaxime (MESH:D002439), 2-bromo-1-(3,5-bromo-2-hydroxyphenyl)ethan-1-one (-), -d (MESH:D003903)
- **Species:** Escherichia coli (E. coli, species) [taxon 562], Acinetobacter baumannii (species) [taxon 470], Escherichia coli ATCC 25922 (strain) [taxon 1322345], Homo sapiens (human, species) [taxon 9606], Bacteria Latreille et al. 1825 (Bacteria stick insect, genus) [taxon 629395], Staphylococcus aureus (species) [taxon 1280]
- **Cell lines:** ATCC 25923 — Homo sapiens (Human), Lung adenocarcinoma, Cancer cell line (CVCL_0023), HDF-Ad — Homo sapiens (Human), Induced pluripotent stem cell (CVCL_RJ31)

## Figures

4 figures with captions in the complete paper: https://tomesphere.com/paper/PMC12944420/full.md

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Source: https://tomesphere.com/paper/PMC12944420