Novel β-keto-enol Pyrazolic Compounds as Potent Antifungal Agents. Design, Synthesis, Crystal Structure, DFT, Homology Modeling, and Docking Studies

A new family of promising inhibitors bearing beta-keto enol functionality with greatly improved pharmacophore properties has been prepared. Herein, a series of novel derivatives of beta-keto enol group embedded with pyrazolic moiety has been designed and synthesized via a one-step procedure using mixed Claisen condensation in the attempt to develop potential antifungal agents. The structures of the synthesized compounds were confirmed by elemental analysis, FT-IR, ESI/LC-MS, and H-1 and C-13 NMR. In addition, X-ray diffraction analysis (XRD) was used to determine the single crystal structure of compound 10. All of the new compounds have been evaluated for their in vitro antifungal and antibacterial activities. Interestingly, the results indicate that most of the compounds display notable antifungal activity close to that of the benomyl fungicide taken as the standard drug. For the most active compound and for benomyl, a correlation has been evidenced between the experimental antifungal activity and the theoretical predictions by DFT calculations and molecular docking against Fgb1 protein.