- Interaction of aryl tetrazolones with anions: proton transfervs.hydrogen bonding
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In this study, the interaction of two monosubstituted aryl tetrazolones, namely 1-(4-nitrophenyl)-1,4-dihydro-tetrazol-5-one1aand 1-(4-trifluoromethylphenyl)-1,4-dihydro-tetrazol-5-one1b, with anions of varying basicitye.g.hydrogen sulfate (HSO4?), bromide (Br?), nitrate (NO3?), thiocyanate (NCS?), chloride (Cl?) and acetate (AcO?) was investigated in acetonitrile and DMSO. UV and NMR titrations indicated that tetrazolones interact through hydrogen bonding or weak electrostatic interactions with HSO4?, Br?, NO3?, NCS?, and Cl?. The association constants (Ka) were found to be in the order Cl?> Br?> NO3?> NCS?> HSO4?. Tetrazolones1a,bexhibited almost 9 times higher selectivity towards Cl?compared to Br?which may be attributed to the higher basicity of the former. The affinity of1atowards most anions was higher than1b, except for HSO4?. This was attributed to the higher electron withdrawing ability of the -NO2group compared to -CF3that renders the N-H proton more acidic for interaction with anions resulting in higherKavalues. Significant UV changes were observed upon addition of the AcO?anion to the solution of1a,bin acetonitrile as new bands formed and isosbestic points were observed indicating the formation of a new species. NMR titrations in DMSO-d6further confirmed that1a,bunderwent deprotonation with AcO?owing to its higher basicity.
- Nord, Erika,Rayat, Sundeep,Zhou, Hanyang
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supporting information
p. 14184 - 14192
(2021/08/16)
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- An optimised series of substituted N-phenylpyrrolamides as DNA gyrase B inhibitors
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ATP competitive inhibitors of DNA gyrase and topoisomerase IV have great therapeutic potential, but none of the described synthetic compounds has so far reached the market. To optimise the activities and physicochemical properties of our previously reported N-phenylpyrrolamide inhibitors, we have synthesized an improved, chemically variegated selection of compounds and evaluated them against DNA gyrase and topoisomerase IV enzymes, and against selected Gram-positive and Gram-negative bacteria. The most potent compound displayed IC50 values of 6.9 nM against Escherichia coli DNA gyrase and 960 nM against Staphylococcus aureus topoisomerase IV. Several compounds displayed minimum inhibitory concentrations (MICs) against Gram-positive strains in the 1–50 μM range, one of which inhibited the growth of Enterococcus faecalis, Enterococcus faecium, S. aureus and Streptococcus pyogenes with MIC values of 1.56 μM, 1.56 μM, 0.78 μM and 0.72 μM, respectively. This compound has been investigated further on methicillin-resistant S. aureus (MRSA) and on ciprofloxacin non-susceptible and extremely drug resistant strain of S. aureus (MRSA VISA). It exhibited the MIC value of 2.5 μM on both strains, and MIC value of 32 μM against MRSA in the presence of inactivated human blood serum. Further studies are needed to confirm its mode of action.
- Tiz, Davide Benedetto,Skok, ?iga,Durcik, Martina,Toma?i?, Tihomir,Ma?i?, Lucija Peterlin,Ila?, Janez,Zega, Anamarija,Draskovits, Gábor,Révész, Tamás,Nyerges, ákos,Pál, Csaba,Cruz, Cristina D.,Tammela, P?ivi,?igon, Du?an,Kikelj, Danijel,Zidar, Nace
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p. 269 - 290
(2019/02/20)
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- Reactions of dimethyl 2-chloroethynylphosphonate with 1-substituted 5-oxo-1H-1,2,3,4-tetrazoles
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Addition of 1-substituted tetrazol-5-ones to dimethyl 2-chloroethynylphosphonate occurred regioselectively to form new geminally substituted bis(4-R-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)ethenylphosphonates with 65- 92% yield.
- Mel'nikova,Myznikov,Dogadina,Svintsitskaya
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p. 2160 - 2166
(2015/02/02)
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- Electronic properties of 1-methyl-4-phenyl-1H-tetrazole-5(4H)-thiones: An experimental and theoretical study
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The syntheses of 1-(4-methoxyphenyl)-4-methyl-1H-tetrazol-5(4H)-thione 1a, 1-methyl-4-phenyl-1H-tetrazole-5(4H)-thione 1b, 1-(4-chlorophenyl)-4-methyl-1H-tetrazol-5(4H)-thione 1c, 1-methyl-4-(4-nitrophenyl)-1H-tetrazol-5(4H)-thione 1d were carried out and their electronic absorption spectra were obtained in cyclohexane, THF, and acetonitrile. The UV spectra of 1a-d showed a modest dependence on the polarity of the solvent. The change of substituent on the tetrazolethione ring from a strongly electron donating group (p-C6H4OMe, 1a), to a moderately electron donating (C6H5, 1b) to a weakly electron withdrawing group (p-C6H4Cl, 1c) also produced minimal effect on the electronic properties of 1a-c. However, the presence of a strongly electron withdrawing group (p-C6H4NO2, 1d) on the heterocyclic ring produced a marked change in the UV spectrum. Time-dependent density functional calculations revealed that all the bands result from π → π* excitations with some degree of intramolecular charge transfer (ICT) within the molecules. Our studies further showed that as the acceptor strength is increased in the order: 1a (p-C6H4OMe) 6H5) 6H4Cl) 6H4NO2), the ICT also increases. In accordance with the experimental observations, the calculated transitions also showed modest dependence on the polarity of the solvent.
- Rayat, Sundeep,Chhabra, Radhika,Alawode, Olajide,Gundugola, Aditya S.
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experimental part
p. 38 - 45
(2010/02/16)
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- NOVEL SULFONAMIDE SUBSTITUTED CHROMAN DERIVATIVES USEFUL AS BETA-3 ADRENORECEPTOR AGONISTS
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This invention relates to novel sulfonamide substituted chroman derivatives which are useful in the treatment of beta-3 receptor mediated conditions.
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Page/Page column 28
(2008/12/07)
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- SULFONAMIDE SUBSTITUTED CHROMAN DERIVATIVES USEFUL AS BETA 3 ADRENORECEPTOR AGONISTS
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This invention related to novel sulfonamide substituted chroman derivatives which are useful in the treatment of beta-3 receptor mediated conditions.
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- Tetrazoles: XXXVIII. Reactions of 5-methylthio-and 5-methylsulfonyl-1-(4-nitrophenyl)tetrazoles with O-nucleophiles
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5-Methylthio-1-(4-nitrophenyl)tetrazole reacts with O-nucleophiles such as HO- and AlkO- to form 1-(4-nitrophenyl)tetrazol-5(4H)-one and 5-alkoxy-1-(4-nitrophenyl)tetrazoles, respectively. Replacement of the methylthio group in the substrate by methylsulfonyl group strongly increases its reactivity, so that 5-methylsulfonyl-1-(4-nitrophenyl)tetrazole is a promising starting compound for synthesis of functionally substituted tetrazoles.
- Koreneva,Koldobskii
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p. 1511 - 1515
(2007/10/03)
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- Reactions of Trimethylsilyl Azide with Heterocumulenes
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Trimethylsilyl azide (TMSA) reacted with aryl isocyanates to give arylcarbamoyl azides, 1-aryl-5(4H)-tetrazolinones, and / or 1-aryl-4-(arylcarbamoyl)-5(4H)-tetrazolinones, whose yields were dependent on the reaction conditions.The reaction between TMSA and benzoyl or thiobenzoyl isocyanates provides a facile method for the preparation of 5-aryl-3-hydroxy-1,2,4-oxadiazoles or -1,2,4-thiadiazoles, respectively.However, with phenyl or benzoyl isothiocyanate, 1-anilino-1,2,3,4-thiatriazole or benzoylcyanamide was obtained in low yield, respectively.TMSA reacted with carbodiimides to afford the corresponding 5-aminotetrazoles.Tetraphenylsuccinimide, N-(diphenylacetyl)tetraphenylsuccinimide, 1,3-bis(diphenylmethyl)urea, and / or benziloylamide were obtained from the reaction of TMSA with diphenyl ketene.The pathways for the formation of the above products are also described.
- Tsuge, Otohiko,Urano, Satoshi,Oe, Koji
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p. 5130 - 5136
(2007/10/02)
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