BackgroundMulti drug-resistant and mycobacterial infections are a major public health challenge, leading to high mortality and socioeconomic burdens through worldwide. Novel therapeutics are necessary to treat the drug resistant strains, since no new chemical entities are emerged in the last four decades for the treatment of TB.FindingsA series of novel 2-heterostyrylbenzimidazole derivatives were synthesised by cyclisation of (3,4-diaminophenyl)(phenyl)methanone, cinnamic acid using glycerol in high yield. The molecular structures of target compounds (5a–5n) were confirmed by 1H and 13C NMR spectroscopy and mass spectrometry. Newly synthesized compounds were screened for anti-tubercular activity and the MIC was determined against Mycobacterium tuberculosis H37Rv by broth microdilution method using Lowenstein Jensen medium (LJ). These compounds docked into the active site of “Crystal structure of pantothenate synthetase in complex with 2-(2-(benzofuran-2-ylsulfonylcarbamoyl)-5-methoxy-1H-indol-1-yl)acetic acid” (PDB code, 3IVX). Auto dock 4.2 software was used for docking studies.Results 5d, 5e, 5f, 5g, 5i, and 5l show better activity and the most active inhibitor of tuberculosis 5f showed a promising inhibition of M. tuberculosis with MIC value of 16 μg/mL. The molecules functionalized with electron-donating groups (Cl, O, S, etc.) on different aromatic aldehydes (5a–5n) were found to be more active in inhibiting M. tuberculosis. ConclusionsOn the basis of docking studies, 5f has shown good affinity for the enzyme. Comparison was made with the binding energies of the standard drugs amoxicillin (−34.28 kcal/mol) and ciprofloxacin (−28.20 kcal/mol). Among all the designed compounds, the compound 5f shows highest binding energy with two amino acid interactions Lys160, Val187 (−9.80 kcal/mol).

In the current study we have demonstrated the effectiveness of ultrasound, a source of green energy, in accessing various isoquinolin‐1(2H)‐one derivatives via the sequential two‐step reaction in a single pot. The methodology involved ultrasound assisted Cu‐catalyzed α‐arylation of ketones with 2‐iodobenzamide (via a C−C bond formation) followed by intramolecular cyclization (via the C−N bond formation) in the same pot. The role of ultrasound, catalyst, base and solvent in the current transformation was evaluated and the generality as well as scope of the methodology was examined via synthesizing a variety of compounds in acceptable to good (49–93 %) yields. The application potential of the methodology was demonstrated further via synthesizing a reported bioactive arylisoquinolinamine derivative of medicinal significance. Further, the encouraging inhibition of TNF‐α in vitro (>50 % at 10 μM) was shown by some of the synthesized compounds e. g. 3 j, 3 m and 3 p.

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A simple and efficient protocol for microwave-assisted solvent-free, green and environmentally friendly synthesis of quinolinyl-1, 2, 4-s-triazolo [4, 3-a]quinoxalines 4 Using iodobenzene diacetate is reported.

A series of novel indole derivatives bearing pyrimidine and cyclic imide scaffolds such as phthalic and maleic anhydrides has been designed and synthesized using both conventional and microwave irradiation (MW) methods under solvent free conditions. The title compounds have been developed by the reaction of 2-aminoo-4-hydroxy-6-(5,1-substituted-indol-3-yl) pyrimidine-5-carbonitrile with phthalic and maleic anhydrides individually using MW method. In addition, these target compounds were also synthesised under conventional heating method. A considerable increase in the reaction rate has been observed with better yields (90-92%) within 2-6 min using microwave irradiation in comparison to conventional thermal treatment.