Antibacterial activity of transition metal complexes with a tridentate NNO amoxicillin derived Schiff base. Synthesis and characterization

• Published in: Applied organometallic chemistry 2018-07, Vol.32 (7), p.n/a
• Main Authors: Anacona, J.R., Mago, Kysbel, Camus, Juan
• Format: Article
• Language: English
• Subjects: 2,6−diaminopyridine; Amoxicillin; amoxicillin−based Schiff base; antibacterial activity; Antibiotics; Chemical synthesis; Chemistry; Cobalt; Coordination compounds; Copper; E coli; Imines; Magnetic permeability; Mass spectrometry; Metals; Molecular chains; NMR; Nuclear magnetic resonance; Resistance; transition metal complexes; Transition metal compounds; Zinc compounds
• ISSN: 0268-2605; 1099-0739
• DOI: 10.1002/aoc.4374

From the reaction of amoxicillin (1) antibiotic with 2,6−diaminopyridine (2) an amoxicillin−based Schiff base (HL) (3) was obtained and its transition metal Schiff base complexes were synthesized. Spectroscopic and physicochemical techniques, namely, UV−Vis, FT−IR, 1H−NMR, EPR, mass spectrometry, molar conductance, magnetic susceptibility, molecular modelling, together with elemental and thermal analyses, were used to characterize the synthesized compounds. Spectral and magnetic data suggested an octahedral geometry for all the complexes and the general formulae [ML(H2O)3][PF6] (M(II) = Mn2+ (4), Co2+ (5), Ni2+ (6), Cu2+ (7), Zn2+ (8), was proposed for them, where L represents deprotonated tridentate NNO amoxycillin−derived Schiff base. All compounds were screened for antibacterial activity by using agar disc diffusion method. The zinc(II) complex exhibited promising bactericidal activity against E. coli and S. aureus. Transition metal complexes with an amoxicillin−based Schiff base (3) derived from the condensation of amoxicillin antibiotic (1) with 2,6−diaminopyridine (2) were synthesized, characterized and screened for antibacterial activity.