Synthesis of Some New Monocyclic β-Lactams Bearing a Morpholine Moiety at their N1 Positions as Antifungal Agents

The synthesis of 40 new monocyclic β-lactams bearing a morpholine moiety at their N1 positions is described. The structures of these compounds have been confirmed by IR, 1H-NMR, 13C-NMR, Mass spectra and Elemental analysis. The antimicrobial activities of the synthetic compounds have been tested against clinically important fungi including Candida, Aspergillus and Microsporum and Epidermophyton species by broth microdilution method as recommended by CLSI. Inhibition studies showed that some of the tested compounds, in particular those with phenoxy groups, exhibited strong antifungal activities against all tested fungi at concentrations of less than 8 μg/mL, while others only inhibited the growth of dermatophytes or Aspergillus species. These results suggest that the derivatives should be investigated further for possible use in antimicrobial products.