Synthesis, characterization, and inhibition effects of a novel eugenol derivative bearing pyrrole functionalities on the corrosion of mild steel in a HCl acid solution.

Semi-synthetic modifications of natural products have yielded numerous anti-cancer drugs, antimicrobials, and corrosion inhibitors. In this study, eugenol, a natural product, was synthetically modified to generate a novel heterocyclic compound: pyrrole, which forms crystals. The latter is the outcome of the condensation reaction between eugenol hydrazide and 2,5-hexanedione, conducted under reflux ethanol conditions, without a catalyst, achieving a 96% yield.

Crystal structure of (Z)-3-allyl-5-(3-bromo-benzyl-idene)-2-sulfanyl-idene-1,3-thia-zolidin-4-one.

In the title compound, C13H10BrNOS2, the rhodanine (systematic name: 2-sulfanyl-idene-1,3-thia-zolidin-4-one) and the 3-bromo-benzyl-idene ring systems are inclined slightly, forming a dihedral angle of 5.86 (12)°. The rhodanine moiety is linked to an allyl group at the N atom and to the 3-bromo-benzyl-idene ring system.

Corrosion resistance of NiTi in fluoride and acid environments.

The aim of our study was to assess in the laboratory the electrochemical behavior of nickel-titanium alloy (NiTi) by simulating the aggressive conditions found in the mouth (notably fluoride and acidity) in order to determine its biocompatibility. The impact of fluoride and pH acid on the corrosion resistance of orthodontic NiTi was studied using classic electrochemical measurement techniques including follow-up over time of the corrosion potential, polarization measurements and impedance spectroscopy. In addition, scanning electron microscopy was used to evaluate the status of the alloy surface before and after immersion in the different media.