Search

1H-Indole-2,3-dione 3-[4-(4-sulfamoylphenyl)thiosemicarbazones] 6a-j were evaluated against para-influenza-3, reovirus-1, sindbis, coxsackie B4, and Punto Toro viruses. New 1-methyl-1H-indole-2,3-dione 3-[4-(4-sulfamoylphenyl) thiosemicarbazones] 7a-c were synthesized to evaluate the contribution of methyl substitution at position 1 of the indole ring to antiviral activity. The test results showed that 5-trifluoromethoxy substituted compound 6c (EC50 2-9 μM) and 5-bromo substituted 6f (EC50 2-3 μM) have non-toxic selective antiviral activity, while not all standards are active against reovirus-1. Molecular docking studies of 6c and 6f were carried out to determine the possible binding positions with reovirus-1. Trifluoromethoxy and bromine substitutions at position 5 of the indole ring provided selective antiviral activity, while methyl substitution at position 1 of the indole ring significantly decreased the activity against reovirus-1 and increased toxicity. [ABSTRACT FROM AUTHOR]

Synthesis of 1-[(2,2-dimethyl-1,3-dioxolan-4-yl)methyl]-1H-indole- -2,3-dione (10) was achieved by coupling 1H-indole-2,3-dione (16) with (R)- -(2,2-dimethyl-1,3-dioxolan-4-yl)methyl 4-methylbenzenesulfonate (15) in the presence of sodium hydride in dry N,N-dimethylformamide at room temperature in a closed Erlenmeyer flask. Condensation of 10 with hydrazinecarbothioamide in water afforded the thiosemicarbazone derivative 17; its subsequent cyclization with potassium carbonate in water gave the corresponding thione 18 in good yield. The 3-allylthio and 3-benzylthio derivatives 20 and 21 were also prepared by alkylating thiol 19 with alkyl halides in aqueous sodium hydroxide or coupling of 3-(allylthio/benzylthio)-5H-1,2,4-triazino[5,6-b]indoles (23 and 24) with compound 15 in NaH/DMF. Compound 20 was isomerized to a mixture of geometrical isomers (E/Z)-5-[(2,2-dimethyl-1,3-dioxolan-4-yl)- methyl]-3-(prop-1-en-1-ylthio)-5H-1,2,4-triazino[5,6-b]indoles (25 and 26), evidenced by their 1H- and 13C-NMR spectra taken in deuterodimethyl sulfoxide. Structural elucidation of the synthesized compounds was realized using FT-IR, 1H-NMR, 13C-NMR, mass spectrometry and elemental analysis. The newly synthesized compounds were found to possess moderate inhibitory activity against the fungus Candida albicans compared to clotrimazole as reference control. Compounds 10, 17, 19, 20, 21, 23 and 24 had mean growth inhibition zones (IZ) and minimal inhibitory concentrations (MIC) in the range of 12–15 mm and 31.25–200 μg mL-1, respectively, with inhibition levels in the range 70.58–88.23 %. Compound 19 exhibited moderate activity against Gram-positive bacteria Staphylococcus aureus relative to imipenem as the standard drug. All compounds were inactive against Escherichia coli and Pseudomonas aeruginosa.

Abstract: New series of 5-fluoro-1H-indole-2,3-dione-3-thiosemicarbazones 2a–k and 5-fluoro-1-morpholino/piperidinomethyl-1H-indole-2,3-dione-3-thiosemicarbazones 3a–r were synthesized. The structures of the synthesized compounds were confirmed by spectral data, elemental and single crystal X-ray diffraction analysis. The new 5-fluoro-1H-indole-2,3-dione derivatives, along with previously reported 5-nitro-1H-indole-2,3-dione-3-thiosemicarbazones 2l–v, 1-morpholino/piperidinomethyl-5-nitro-1H-indole-2,3-dione-3-thiosemicarbazones 4a–l, and 5-nitro-1H-indole-2,3-dione-3-[(4-oxo-1,3-thiazolidin-2-ylidene)hydrazones] 5a–s, were evaluated for in vitro antituberculosis activity against Mycobacterium tuberculosis H37Rv. Among the tested compounds, 5-nitro-1H-indole-2,3-dione-3-thiosemicarbazones (2p, 2r, and 2s) and its 1-morpholinomethyl derivatives (4a, 4e, 4g, and 4i) exhibited significant inhibitory activity in the primary screen. The antituberculosis activity of molecules with diverse skeletons was investigated by means of the Electronic-Topological Method (ETM). Ten pharmacophores and ten anti-pharmacophores that have been found by this form the basis of the system capable of predicting the structures of potentially active compounds. The forecasting ability of the system has been tested on structures that differ from those synthesized. The probability of correct identification for active compounds was found as equal to 93% in average. To obtain the algorithmic base for the activity prediction, Artificial Neural Networks were used after the ETM (the so-called combined ETM–ANN method). As the result, only 9 pharmacophores and anti-pharmacophores were chosen as the most important ones for the activity. By this, ANNs classified correctly 94.4%, or 67 compounds from 71. [Copyright &y& Elsevier]