X-ray crystallographic and structural studies of (benzothiazol-2-yl)ethanesulphonamide, and its antimicrobial properties

Abstract

N-(benzothiazol-2-yl)ethanesulphonamide (ES2ABT) was synthesized by the condensation of 2-aminobenzothiazole and ethanesulphonylchloride in acetone at 130 °C. The resulting crude precipitates were recrystallized in absolute ethanol. ES2ABT was characterized using X-ray crystallography, mass spectrometry, elemental microanalysis, UV/VIS spectrophotometry, infra red, proton and ¹³C NMR spectroscopies. The antimicrobial tests of the compound were carried out on both multi-resistant bacterial strains isolated under clinical conditions and cultured species using agar-well diffusion method. The multi-resistant bacterial strains used were Escherichia coli, Proteus species, Pseudomonas aeroginosa and Staphylococcus aureus which were isolated from dogs. The culture species were Pseudomonas aeruginosa (ATCC 27853), Escherichia Coli (ATCC 25922) Staphylococcus aureus (ATCC 25923), and the fungi, Candida krusei (ATCC 6258) and Candida albicans (ATCC 90028). The tests were both in vitro and in vivo. Thus the Inhibition Zone Diameter (IZD), the Minimum Inhibitory Concentration (MIC), and the Lethal and Effective Concentrations (LC₅₀ and EC₅₀) were determined. The antimicrobial activity of the compound was compared with those of Ciprofloxacin and trimethoprim-sulphamethoxazole as antibacterial agents and Fluconazole as an antifungal drug. The compound showed varying activity against the cultured typed bacteria and fungi used. However, ES2ABT was less active than the antibacterial standard drugs used but not Fluconazole which did not show any activity against Candida krusei (ATCC 6258). The Lethal Concentration (LC₅₀) is 338.80 ± 28.6 ppm. This is within the permissible concentrations.

Key words: N-(benzothiazol-2-yl)ethanesulphonamide, antimicrobial, in vivo, in vitro