Synthesis, antibacterial activity, and CoMFA study of new 1,2,3-triazolyl 7-carboxamidodesacetoxy cephalosporanic acid derivatives

New derivatives of 1,2,3-triazolyl 7-carboxamidodesacetoxy cephalosporanic acid were synthesized using alkyne-azide 1,3-dipolar cycloaddition. The synthesized compounds were evaluated for their antibacterial activity against a collection of Gram-positive and Gram-negative bacteria and also in synergy with cefixime and cephalexin. Some compounds inhibited vancomycin-resistant strain of Enterococcus faecium (MIC = 8 µg/mL) and in the synergy experiments compounds 13a, 13f, and 13g decreased the level of MIC against an ESBL strain of Klebsiella pneumonia. A comparative molecular field analysis has been carried out, and the effect of substituents on the antibacterial activities of the synthesized compounds was explained.