3-(5-(1H-imidazol-1-yl) pent-1-en-1-yl)-9-ethyl-9H-carbazole: synthesis, characterization (IR, NMR), DFT, antimicrobial-antioxidant activities and docking study

Abstract

3-(5-(1H-imidazol-1-yl) pent-1-en-1-yl)-9-ethyl-9H-carbazole called as compound 1 was synthesized and characterized by proton and carbon-13 nuclear magnetic resonance (¹H- and ¹³C- NMR) and Fourier transform infrared (FTIR) spectroscopic methods. Density Functional Theory/Becke, 3-parameter (DFT/B3LYP), for compound 1 were performed with 6-311++G(d,p) method. Optimized geometry, frontier molecular orbitals (HOMO; highest occupied molecular orbital; LUMO: lowest unoccupied molecular orbital), IR and NMR parameters of compound 1 were obtained. The evaluations reveal that the calculation results support the experimental results. In addition, the antimicrobial (a microwell dilution method) and antioxidant activities (2,2-Diphenyl-1-picrylhydrazyl (DPPH), 2,2’-azino-bis-(3-ethylbenzothiazoline-6-sulfonate) (ABTS) ferric ion reducing antioxidant power (FRAP) of compound 1 were evaluated. According to the results obtained, it showed higher antimicrobial activity (Minimal inhibition concentration (MIC): 78.12 µg/mL) against B. subtilis subsp. Spizizenii. Morever, molecular docking studies were carried out to investigate the interactions of an antimicrobial agent on some important enzymes played important roles in nucleic acid (Deoxyribo nucleic acid (DNA) synthesis, cell wall synthesis, protein synthesis, and metabolism etc. The compound 1 was strongly bound to tyrosyl-tRNA synthetase enzyme (binding energy: −11.18 and K_i: 6.37 nM) and Beta-Ketoacyl-Acp Synthase III enzyme (binding energy: −10.29 and K_i: 28.47 nM).

Communicated by Ramaswamy H. Sarma

Keywords:

• Carbazole
• FTIR
• NMR
• DFT
• antimicrobial-antioxidant activities
• molecular docking study

Acknowledgements

This work was supported by the Scientific research Project of Karadeniz Technical University (KTU-BAP) [grant numbers 8662]. The numerical calculations reported in this paper were fully performed at TUBITAK ULAKBIM, High Performance and Grid Computing Center (TRUBA resources). Instrumentation, Determination of antioxidant and antimicrobial activities were submitted in Supplementary file.

Disclosure statement

No potential conflict of interest was reported by the authors.