Structural Characterization, DFT Calculation, NCI, Scan-Rate Analysis and Antifungal Activity againstBotrytis cinereaof (E)-2-{[(2-Aminopyridin-2-yl)imino]-methyl}-4,6-di-tert-butylphenol (Pyridine Schiff Base)

Botrytis cinereais a ubiquitous necrotrophic filamentous fungal phytopathogen that lacks host specificity and can affect more than 1000 different plant species. In this work, we exploredL1[(E)-2-{[(2-aminopyridin-2-yl)imino]-methyl}-4,6-di-tert-butylphenol], a pyridine Schiff base harboring an intramolecular bond (IHB), regarding their antifungal activity againstBotrytis cinerea. Moreover, we present a full characterization of theL1by NMR and powder diffraction, as well as UV-vis, in the presence of previously untested different organic solvents. Complementary time-dependent density functional theory (TD-DFT) calculations were performed, and the noncovalent interaction (NCI) index was determined. Moreover, we obtained a scan-rate study on cyclic voltammetry ofL1. Finally, we tested the antifungal activity ofL1against two strains ofBotrytis cinerea(B05.10, a standard laboratory strain; and A1, a wild type strains isolated from Chilean blueberries). We found thatL1acts as an efficient antifungal agent againstBotrytis cinereaat 26 degrees C, even better than the commercial antifungal agent fenhexamid. Although the antifungal activity was also observed at 4 degrees C, the effect was less pronounced. These results show the high versatility of this kind of pyridine Schiff bases in biological applications.