Synthesis and antimicrobial activities of some new sulfonyl phenoxides

Abstract

Four new sulfonyl phenoxides were synthesized through O-sulfonylation reaction of phenolic compounds with 5-chloro-1-ethyl-2-methylimidazole-4-sulfonyl chloride in good yield. FT-IR, 1H-NMR, 13C-NMR, and DEPT 135 NMR were carried out to characterize and the thin layer chromatography (TLC) confirm the purity. Antimicrobial activities of the sulfonyl phenoxides against Gram-positive (methicillin-susceptible Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, and Bacillus subtilis), Gram-negative (Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae), and Candida albicans were carried out using the standard microbiological method. The antimicrobial activities were referenced to ciprofloxacin and itraconazole, antibacterial and antifungal drug respectively. The in vitro antimicrobial studies of 5-chloro-1-ethyl-2-methyl-1H-imidazole-4-sulfonyl(4-chloro-3-methyl)phenoxide and 5-chloro-1-ethyl-2-methyl-1H-imidazole-4-sulfonyl-2-methylphenoxide showed moderate activity against C. albicans. The four sulfonyl phenoxides had weak activities against Gram-positive and Gram-negative bacteria.
 Keywords: Sulfonyl phenoxides, Antimicrobial, Phenolic compounds, O-Sulfonylation reaction

Synthesis and Anticandidal and Antibacterial Activities of 5-Chloro-1-Ethyl-2-Methyl-N-Phenyl-1h-Imidazole-4-Sulphonamide and 5-Chloro-N-(3-Chlorophenyl)-1-Ethyl-2-Methyl-1h-Imidazole-4-Sulphonamide

“…The FT-IR spectra of sulphonamides shown absorption bands of -SO 2 NH, C=N, and Ar C-H at 3155-3109, 1636-1633, and 3071-3064 cm −1 respectively (Table 2). In 1 H NMR spectra, alkyl groups resonated as expected in line with literature data [38][39] (Table 3). The NH of the sulphonamides appeared as a singlet around 10.37-10.71 as most deshielded proton.…”

“…Diethyl oxalate (i) (15 mL) in a dropping funnel was added drop-wise to a chilled 16.5 mL of 70% aqueous ethylamine in an ice-water bath with constant stirring. The white crystals formed were filtered under vacuum, triturated in cold water, and air-dried to produce 13.01 g N, N 1 diethyloxamide (ii) (83%), MP 179-180 °C and IR: 3287, 2859, 1638, 1377, 1226, 1148, 821, and 770 cm -1 [38] (Scheme 1).…”

“…The mixture was left overnight at room temperature. Then the solution was chilled and made alkaline with 50% Na 2 CO 3 solution until dark brown organic layer separated with the help of in situ sodium chloride formed (salting-out liquid-liquid extraction) and pipetted out to give (15.25 g, 75.51%) with a single spot on thin-layer chromatography, used without further purification R f, 83.33% in CHCl 3 (Scheme 1) [38]. IR: 2981, 2859, 1638, 1508, 1495, 1430, 1383, 1260, 1148, 820 and 660 cm -1 .…”

“…Chilled distilled chlorosulphonic acid (45 mL, 0.680 mol) was carefully added to 5-chloro-1ethyl-2-methylimidazole (iii) (10 g, 0.0692 mol) carefully, portion-wise. The reaction flask was fitted to a calcium chloride guard tube and then heated under reflux for 3 h. The solution was cooled, poured in crushed ice and filtered immediately under vacuum to get brownish solid product (iv) (9 g, 53.52%) used without further purification R f, 88.56 in CHCl 3 [38]. IR: 2981, 2853, 1638, 1508, 1498, 1437, 1377, 1351, 1263, 1226, 1187, 1142, 787, 722, 666 cm -1 (Scheme 1).…”

Identification and Pharmacological Activities of Secondary Metabolites of Phytochemicals

“…Quinine extracted from Cinchona tree are used in the treatment of malaria and has served as a source of many other drugs. and cosmetics production because of their organoleptic properties; color, aroma, taste, and astringency [10]. The biological activities of phenolic compounds are exploited in pharmaceutical industries because of their antiinflammatory, antioxidant, anti-hypertensive, anti-microbial, hepatoprotective properties, antidiabetic, and anticancer, etc.…”