Bio-screening of new series of β-lactams with spectroscopic characterization

The excellent potential behavior of novel synthesized series of β-lactams with antibacterial and insecticidal activity provide the path way to design novel drugs. The compound B-6 is twofold active against Escherichia coli, B-4 against Pseudomonas aeruginosa and B-1 and B-3 against Klebsiella pneumoniae as to standard drug. The compound B-2 exhibited excellent potential with LD₅₀ 19.95 μg/mL against mealybug grown on cotton plants as compared to others. Almost all the synthesized compounds were bearing potential activity against Monomorium minimum and Tribolium castaneum. FTIR data revealed carbonyl absorption of the β-lactams in the range of 1720-1690_asym cm^–1, 1650-1580_sym cm^–1 and disappearance of the C=N absorption peak of imines 1620-1640 cm^–1. The ¹HNMR spectra confirmed the synthesis by the disappearance of imines proton at 8.69-8.78 ppm and appearance of C-2, C-3 protons of β-lactam ring at 1.90-3.30 ppm.