One-pot synthesis, crystal structure and antimicrobial activity of 6-benzyl-11-(p-tolyl)-6H-indolo[2,3-b] quinoline

The title compound 6-benzyl-11-(p-tolyl)-6H-indolo[2,3-b]quinoline 3 was synthesized by one-pot procedure including electrophile-driven cross-amination and cyclization via Friedel-Crafts alkylation. The crystal structure of this indoloquinoline was determined by means of single-crystal X-ray diffraction method and further confirmed by H-1 NMR and C-13 NMR. In tetracyclic compound 3 all the C-N bonds are shorter than single bonds but longer than double bonds which show significant electrons delocalization. Furthermore, the crystal packing is stabilized by the presence of pi-pi stacking interaction and C-H-pi interaction. In addition, the antimicrobial studies revealed that the title compound exhibits strong antimicrobial activity against Aspergillus niger, Fusarium oxysporum, P. syringe and B. subtilis. (C) 2020 Elsevier B.V. All rights reserved.