The antimicrobial activity of the synthesized derivatives (collected from chemistry
department) was evaluated using a broth dilution method against bacterial pathogens. The
concentration of compounds was 1.5mg/ml. Ciprofloxacin was a reference compound to
be used as positive control. The compounds exhibited percent antibiosis against
Escherichia coli (37.40-99.83), Pseudomonas aeruginosa (0-99.51),Staphylococus
aureus (27.12-99.42) and Klebsiella sp. (7.80-99.82).2,2'-((1E,1'E)-(1,2-
phenylenebis(azanylylidene))bis(methanylylidene))diphenol(AS-42) and 2-((E)-2-((2-
((E)-(2-hydroxybenzylidene)amino)-ethyl)imino)ethyl)phenol zinc(II)(AS-51) showed
antibiosis (90%) against Klebsiella sp. and S.aureus. 2,2'-((1E,1'E)-(1,2-
phenylenebis(azanylylidene))-bis(methanylylidene))diphenolzinc(II)(AS-46) showed
maximum antibiotic potential (99%) against (Escherichia coli and Pseudomonas
aeruginosa).2,2'-((1E,1'E)-(1,2-phenylenebis(azanylylidene))bis(methanylylidene))
diphenolcobalt(II(AS-45), Bis((E)-2-((pyrimidin-2-ylimino)methyl)phenol)copper(II)
(AS-54), Bis((E)-2-((pyrimidin-2-ylimino)methyl)phenol)plumb(II)(AS-53) were
resistant to P.aeruginosa whereas susceptible to other three pathogens. Analysis of the
structure-activity relationship showed that testing Schiff bases lead to more potent
derivatives with a broader spectrum of antibacterial activity.
Key words: Schiff bases, metallic complexes and Schiff base, clinical and susceptibility
testing. Multi drug resistance, Antimicrobial agents, antibiosis