SYNTHESIS, CHARACTERIZATION AND ANTIBACTERIAL ACTIVITY OF SOME ANTHRAQUINONE DYE DERIVATIVES
A. AJAYI OLUFUNMILAYO *
Department of Chemistry, Faculty of Physical Sciences, University of Ilorin, P.M.B 1515, Ilorin, Nigeria
A. OLATUNJI GABRIEL
Department of Industrial Chemistry, Faculty of Physical Sciences, University of Ilorin, P.M.B 1515, Ilorin, Nigeria
*Author to whom correspondence should be addressed.
Abstract
Microbial infections have been a major source of morbidity and mortality worldwide. This problem is exacerbated by widespread resistance to antibiotics, emergence of new pathogens and the lack of effective new therapeutics. In an effort to contribute to solving this problem, seven anthraquinone dye derivatives with potential antibacterial properties were synthesized. Characterization was carried out using Fourier Transform Infrared spectroscopy (FTIR), Ultraviolet-Visible spectroscopy (UV) and Nuclear Magnetic Resonance spectroscopy (NMR). These compounds were investigated for their antibacterial activities on eight types of gram positive and gram negative bacteria using some standard antibiotics namely; Septrin (Trimethoprim/sulfamethoxazole), Chloramphenicol (2,2-dichloro-N-[1,3-dihydroxy-1-(4-nitrophenyl)propan-2-yl]acetamide), Spafloxacin (5-Amino-1-cyclopropyl-7-[(3R,5S)-3,5-dimethyl-1-piperazinyl]-6,8-difluoro-4-oxo-1,4-dihydro-3-quinolinecarboxylic acid), Ciprofloxacin (1-cyclopropyl-6-fluoro-4-oxo-7-piperazin-1-yl-quinoline-3-carboxylic acid), Amoxicilin (2S,5R,6R)-6-{[(2R)-2-amino-2-(4-hydroxyphenyl)-acetyl]amino}-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-24-carboxylic acid), Augmentin (Amoxicillin/clavulanic acid), Gentamycin (3R,4R,5R)-2-{[(1S,2S,3R,4S,6R)-4,6-diamino-3-{[(2R,3R,6S)-3-amino-6-[(1R)-1-(methylamino)ethyl]oxan-2-yl]oxy}-2-hydroxycyclohexyl]oxy}-5-methyl-4-(methylamino)oxane-3,5-diol), Perfloxacin (1-ethyl-6-fluoro-7-(4-methylpiperazin-1-yl)-4-oxo-quinoline-3-carboxylic acid), Tarivid(9-Fluoro-3-methyl-10-(4-methyl-1-piperazinyl)-7-oxo-2,3-dihydro-7H-[1,4]oxazino[2,3,4-ij]quinoline-6-carboxylic acid and Streptomycin (5-(2,4-diguanidino-3,5,6-trihydroxy-cyclohexoxy)-4-[4,5-dihydroxy-6-(hydroxymethyl)-3-methylamino-tetrahydropyran-2-yl]oxy-3-hydroxy-2-methyl-tetrahydrofuran-3-carbaldehyde), as comparisons. Derivatives carrying para-substituents showed significant antibacterial activity than the ortho and meta isomers. Significant antibacterial activity was observed for two of the compounds over that of the standard antibiotics: Bram/p-Anisidine showed higher activity than the standards on Escherichia coli and Pseudomonas aeruginosa with minimum inhibitory concentration (MIC) values of 2.5 µg/mL and 25 µg/mL respectively. Bram/p-Iodoaniline was a very potent inhibitor of Bacillus cereus and Pseudomonas aeruginosa than the standard antibiotics with MIC values of 2.5 µg/mL and 2.5 µg/mL.
Keywords: Anthraquinone, antibacterial, antibiotics, synthesis, derivatives