Synthesis and antifungal activity of camphoric acid-based acylhydrazone compounds

In the search of novel potent bioactive compounds, 18 novel camphoric acid-based acylhydrazone compounds 4a-4r were designed and synthesized by the condensation reaction of N-amino camphorimide (3) with substituted benzaldehyde based on camphoric acid as the starting material. The target compounds were characterized by means of Fourier transform infrared (FTIR), H-1 nuclear magnetic resonance (NMR), C-13 NMR, electrospray ionization-mass spectrometry (ESI-MS), and elemental analysis. The preliminary bioassay showed that the following camphoric acid-based compounds exhibited excellent antifungal activity with an inhibition ratio of 95% against Physalospora piricola at the concentration of 50 mu g ml(-1): o-bromophenyl acylhydrazone (4f), p-bromophenyl acylhydrazone (4g), p-methoxyphenyl acylhydrazone (4m), and p-hydroxyphenyl acylhydrazone (4p).