Synthesis, molecular docking and in vitro antimicrobial studies of new hexahydroindazole derivatives of curcumin

A series of hexahydroindazole analogues of curcumin were synthesized and investigated for in vitro and in silico antimicrobial activity. The structures of synthesized compounds were identified on the basis of satisfactory analytical and spectral data (¹H NMR, ¹³C NMR, EI-MASS techniques and elemental analysis). Synthesized compounds showed moderate to high activity against both bacterial and fungal strains. All compounds were docked computationally to the active site of enzyme L-glutamine: D-fructose-6-phosphate amido-transferase [GlcN-6-P] (EC 2.6.1.16). The autodock programme 4.0 was employed to perform automated molecular docking. (E)-1-(7-(3-methoxybenzylidene) -3-(3- methoxyphenyl)-3,3a,4,5,6,7-hexahydro-2H-indazol-2-yl)ethanone (A7) turned out to be the most potent analogue of the series, showing best activity against bacterial and fungal strains. Compound A7 showed minimum binding and docking energy and may be considered as good inhibitor of GlcN-6-P synthase. Further investigation and optimization of this lead could provide new antimicrobial molecules.