Synthesis and evaluation of antibacterial activity for a series of N-phthaloylglycine derivatives

Abstract

Two series of N-phthaloylglycine derivatives were synthesized under Schotten-Baumann conditions. The first series consists of N-phthaloylglycine amides (4a-h), and the second one consists of benzimidazole derivatives of N-phthaloylglycine (6a-d). All the synthesized analogues were evaluated for their in vitro antimicrobial activity by using disc diffusion method. In the first series, compounds 4h (MIC, 0.5 mg/L), 4a (MIC, 0.6 mg/L), and 4e (MIC, 0.7 mg/L) were found to be the most potent against vancomycin-resistant Staphylococcus aureus (VRSA). Furthermore, three compounds i.e. 4g (MIC, 0.8 mg/L), 6b (MIC, 1.5 mg/L), and 4h (MIC, 1.6 mg/L) displayed good activity against methicillin-resistant Staphylococcus aureus (MRSA). All the synthesized compounds exhibited a wide range of antibacterial activity against all of the Staphylococcus aureus resistant strains tested. The structures of the synthesized compounds were characterized by IR, ¹H NMR, ¹³C NMR and MS (EI).