Design, synthesis and biological evaluation of phenylacridine based antibacterial agent

Authors

  • KWTRT de Silva Department of Chemistry, Faculty of Science, Colombo 08
  • RP Perera Department of Chemistry, Faculty of Science, Colombo 08
  • CM Nanayakkara Department of Chemistry, Faculty of Science, Colombo 08

Abstract

Objective: The rapid development of multidrug resistant pathogenic bacteria and shortage of new antimicrobial agents prompted us to develop a novel antimicrobial agent with less toxicity to humans.  Discovery of penicillin outrivaled acridine, a medicinally important heterocyclic nucleus, but extensive increase of bacterial drug resistance captures scientists’ consideration to acridine again. The present study is to develop an acridine based new antimicrobial agent.

Method: An organic synthesis was carried out to synthesize the novel acridine derivative of 9-phenyl-10-(2-phenylalkyl)acridinium bromide. The formation of the compound was confirmed using 1H-NMR analysis; (acetone, δ, ppm): 3.8 (s,2H), 5.0 (s,2H), 7.24-7.47 (m,8H), 7.8-7.4 (m,5H), 8.0-7.8 (m,5H). In vitro antimicrobial activities of 9-phenyl-10-(2-phenylalkyl)acridinium bromide was measured against Gram positive Staphylococcus aureus and against Gram negative Escherichia coli from disk diffusion method using gentamycin as the positive control.

Results: S.aureus showed a higher antibacterial activity (12 mm for 2 µl/ml) than activity (11 mm for 2 µl/ml) against E.coli for 9-phenyl-10-(2-phenylalkyl)acridinium bromide. For grntamycin (3000 µg/ml), inhibition for S.aureus was 24 mm and for E.coli it was 23 mm. The MIC for S.aureus was 3 x 10-4 µl/ml and the MIC for E.coli was 1 x 10-2 µl/ml. The density of the novel compound is apparently higher than that of water. Therefore these MIC values should be lesser than 0.3 µg/ml and 10 µg/ml respectively.

Conclusion: Strong antibacterial activity of 9-phenyl-10-(2-phenylalkyl)acridinium bromide against S.aureus and E.coli indicates that there is a possibility to use it as an effective antibacterial agent.

Author Biographies

KWTRT de Silva, Department of Chemistry, Faculty of Science, Colombo 08

Department of Chemistry,Faculty of Science,Colombo 08

RP Perera, Department of Chemistry, Faculty of Science, Colombo 08

Department of Chemistry,Faculty of Science,Colombo 08

CM Nanayakkara, Department of Chemistry, Faculty of Science, Colombo 08

Department of Chemistry,Faculty of Science,Colombo 08

Published

2012-12-30