Antifungal activity and tautomeric cyclization equilibria of formylphenylboronic acids

Bioorg Chem. 2019 Oct:91:103081. doi: 10.1016/j.bioorg.2019.103081. Epub 2019 Jun 25.

Abstract

2-Formylphenylboronic acid and four isomeric fluoro-2-formylphenylboronic acids have been found active against a series of fungal strains: Aspergillus, Fusarium, Penicillium and Candida. The level of antifungal activity was evaluated by agar diffusion tests as well as the determination of minimum inhibitory concentrations (MICs) by serial dilution method. Among the tested compounds, 4-fluoro-2-formylphenylboronic acid - an analogue of the known antifungal drug Tavaborole (AN2690) - proved to be the most potent antifungal agent. The tautomeric equilibrium leading to the formation of 3-hydroxybenzoxaboroles as well as the position of the fluorine substituent were revealed to play a crucial role in the observed activity.

Keywords: Antifungal activity; Cyclization equilibria; Formylphenylboronic acid; Organoboron compounds; Tautomerization.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antifungal Agents / chemical synthesis
  • Antifungal Agents / chemistry
  • Antifungal Agents / pharmacology*
  • Aspergillus / drug effects*
  • Boronic Acids / chemical synthesis
  • Boronic Acids / chemistry
  • Boronic Acids / pharmacology*
  • Candida / drug effects*
  • Cyclization
  • Dose-Response Relationship, Drug
  • Fusarium / drug effects*
  • Microbial Sensitivity Tests
  • Molecular Structure
  • Penicillium / drug effects*
  • Structure-Activity Relationship

Substances

  • Antifungal Agents
  • Boronic Acids