Synthesis, structural characterization, hirshfeld surface, DFT calculation and antifungal activity of novel quinoline carbonothioate compounds

Three quinoline carbonothioate compounds were synthesized using o-fluoroaniline and ethyl 2-methylacetoacetate as starting materials via multi-steps. The structures of three compounds were confirmed using H-1 NMR and HRMS. The structure of O-ethyl S-(8-fluoro-2,3-dimethylquinolin-4-yl) carbonothioate (<bold>3a</bold>) was further determined through X-ray single-crystal diffraction. Single-crystal X-ray diffraction analysis indicated that compound <bold>3a</bold> crystallizes in the monoclinic space group C2/c, with unit cell parameters: a = 14.3284(6) & Aring;, b = 19.2857(8) & Aring;, c = 10.3990(5) & Aring;, beta = 108.1220(10)degrees, V = 2731.0(2) & Aring;(3). In addition, the physicochemical properties of compound <bold>3a</bold> were calculated and discussed using molecular electrostatic potential, frontier molecular orbital and Hirshfeld surface analysis. The antifungal activity of the three compounds was evaluated at 50 mu g/mL, with compound <bold>3b</bold> exhibiting good activity (75.8%) against R. solani.