Design, Synthesis, and Efficacy Testing of Nitroethylene- and 7-Nitrobenzoxadiazol-Based Flavodoxin Inhibitors against Helicobacter pylori Drug-Resistant Clinical Strains and in Helicobacter pylori-Infected Mice
摘要:
Helicobacter pylori (Hp) infection is the main cause of peptic ulcer and gastric cancer. Hp eradication rates have fallen due to increasing bacterial resistance to currently used broad-spectrum antimicrobials. We have designed, synthesized, and tested redox variants of nitroethylene- and 7-nitrobenzoxadiazole-based inhibitors of the essential Hp protein flavodoxin. Derivatives of the 7-nitrobenzoxadiazole lead, carrying reduced forms of the nitro group and/or oxidized forms of a sulfur atom, display high therapeutic indexes against several reference Hp strains. These inhibitors are effective against metronidazole-, clarithromycin-, and rifampicin-resistant Hp clinical isolates. Their toxicity for mice after oral administration is low, and, when administered individually at single daily doses for 8 days in a mice model of Hp infection, they decrease significantly Hp gastric colonization rates and are able to eradicate the infection in up to 60% of the mice. These flavodoxin inhibitors constitute a novel family of Hp-specific antimicrobials that may help fight the constant increase of Hp antimicrobial-resistant strains.
Synthesis of Chiral Cyclic Nitrones by Asymmetric Addition of β-Ketosulfones to Nitroalkenes followed by Reductive Cyclization
作者:Olga García Mancheño、Pia Tangen、Renate Rohlmann、Roland Fröhlich、José Alemán
DOI:10.1002/chem.201001914
日期:2011.1.17
transformed into chiral nitrones by reduction of the nitro group and in situ cyclization (up to 99:1 e.r. and >98:2 d.r.). Moreover, the utility of this method has additionally been demonstrated by the further transformation to functionalized N‐hydroxypyrrolidines that possess a quaternary center by addition of trimethylsilyl cyanide (TMSCN) to the CN bond of the cyclic nitrones in the presence of a
Direct Synthesis of N-Unsubstituted 4-Aryl-1,2,3-triazoles Mediated by Amberlyst-15
作者:Zu-Li Wang、Hui Zhang、Dao-Qing Dong
DOI:10.1055/s-0035-1560488
日期:——
A highly efficient and effective method for the synthesis of N-unsubstituted 4-aryl-1,2,3-triazoles promoted by Amberlyst-15 is described. The promoter can be recycled and reused up to eight times without any reduction in its catalytic activity.
Substrate Promiscuity of <i>ortho</i>-Naphthoquinone Catalyst: Catalytic Aerobic Amine Oxidation Protocols to Deaminative Cross-Coupling and <i>N</i>-Nitrosation
作者:Tengda Si、Hun Young Kim、Kyungsoo Oh
DOI:10.1021/acscatal.9b03442
日期:2019.10.4
been identified as versatile aerobicoxidationcatalysts. Primary amines were readily cross-coupled with primary nitroalkanes via deaminative pathway to give nitroalkene derivatives in good to excellent yields. Secondary and tertiary amines were inert to ortho-naphthoquinone catalysts; however, secondary nitroalkanes were readily converted by ortho-naphthoquinone catalysts to the corresponding nitrite
Design, Synthesis, and Efficacy Testing of Nitroethylene- and 7-Nitrobenzoxadiazol-Based Flavodoxin Inhibitors against <i>Helicobacter pylori</i> Drug-Resistant Clinical Strains and in <i>Helicobacter pylori</i>-Infected Mice
作者:Sandra Salillas、Miriam Alías、Valérie Michel、Alejandro Mahía、Ainhoa Lucía、Liliana Rodrigues、Jessica Bueno、Juan José Galano-Frutos、Hilde De Reuse、Adrián Velázquez-Campoy、José Alberto Carrodeguas、Carlos Sostres、Javier Castillo、José Antonio Aínsa、María Dolores Díaz-de-Villegas、Ángel Lanas、Eliette Touati、Javier Sancho
DOI:10.1021/acs.jmedchem.9b00355
日期:2019.7.11
Helicobacter pylori (Hp) infection is the main cause of peptic ulcer and gastric cancer. Hp eradication rates have fallen due to increasing bacterial resistance to currently used broad-spectrum antimicrobials. We have designed, synthesized, and tested redox variants of nitroethylene- and 7-nitrobenzoxadiazole-based inhibitors of the essential Hp protein flavodoxin. Derivatives of the 7-nitrobenzoxadiazole lead, carrying reduced forms of the nitro group and/or oxidized forms of a sulfur atom, display high therapeutic indexes against several reference Hp strains. These inhibitors are effective against metronidazole-, clarithromycin-, and rifampicin-resistant Hp clinical isolates. Their toxicity for mice after oral administration is low, and, when administered individually at single daily doses for 8 days in a mice model of Hp infection, they decrease significantly Hp gastric colonization rates and are able to eradicate the infection in up to 60% of the mice. These flavodoxin inhibitors constitute a novel family of Hp-specific antimicrobials that may help fight the constant increase of Hp antimicrobial-resistant strains.