Physicochemical and Theoretical Characterization of a New Small Non-Metal Schiff Base with a Differential Antimicrobial Effect against Gram-Positive Bacteria

Manuel Gacitúa, Alexander Carreño, Rosaly Morales-Guevara, Dayán Páez-Hernández, Jorge I. Martínez-Araya, Eyleen Araya, Marcelo Preite, Carolina Otero, María Macarena Rivera-Zaldívar, Andrés Silva, Juan A. Fuentes

Research output: Contribution to journalArticlepeer-review

Abstract

Searching for adequate and effective compounds displaying antimicrobial activities, especially against Gram-positive bacteria, is an important research area due to the high hospitalization and mortality rates of these bacterial infections in both the human and veterinary fields. In this work, we explored (E)-4-amino-3-((3,5-di-tert-butyl-2-hydroxybenzylidene)amino) benzoic acid (SB-1, harboring an intramolecular hydrogen bond) and (E)-2-((4-nitrobenzilidene)amino)aniline (SB-2), two Schiff bases derivatives. Results demonstrated that SB-1 showed an antibacterial activity determined by the minimal inhibitory concentration (MIC) against Staphylococcus aureus, Enterococcus faecalis, and Bacillus cereus (Gram-positive bacteria involved in human and animal diseases such as skin infections, pneumonia, diarrheal syndrome, and urinary tract infections, among others), which was similar to that shown by the classical antibiotic chloramphenicol. By contrast, this compound showed no effect against Gram-negative bacteria (Klebsiella pneumoniae, Escherichia coli, and Salmonella enterica). Furthermore, we provide a comprehensive physicochemical and theoretical characterization of SB-1 (as well as several analyses for SB-2), including elemental analysis, ESMS,1H and13C NMR (assigned by 1D and 2D techniques), DEPT, UV-Vis, FTIR, and cyclic voltammetry. We also performed a computational study through the DFT theory level, including geometry optimization, TD-DFT, NBO, and global and local reactivity analyses.

Original languageEnglish
Article number2553
JournalInternational Journal of Molecular Sciences
Volume23
Issue number5
DOIs
Publication statusPublished - 1 Mar 2022

Keywords

  • Bacillus cereus
  • Cyclic voltammetry
  • DFT
  • Enterococcus faecalis
  • HPLC-MS
  • Intramolecular hydrogen bond
  • Local reactivity analysis
  • MIC
  • Schiff bases
  • Staphylococcus aureus

ASJC Scopus subject areas

  • Catalysis
  • Molecular Biology
  • Spectroscopy
  • Computer Science Applications
  • Physical and Theoretical Chemistry
  • Organic Chemistry
  • Inorganic Chemistry

Fingerprint

Dive into the research topics of 'Physicochemical and Theoretical Characterization of a New Small Non-Metal Schiff Base with a Differential Antimicrobial Effect against Gram-Positive Bacteria'. Together they form a unique fingerprint.

Cite this