Structure-Activity Relationship of Omeprazole and Analogs as Helicobacter pylori Urease Inhibitors
摘要:
Helicobacter pylori urease belongs to a family of highly conserved urea-hydrolyzing enzymes. A common feature of these enzymes is the presence of two Lewis acid nickel ions and a reactive cysteine residue in the active site. The H+/K(+)-ATPase inhibitor omeprazole is a prodrug of a sulfenamide which covalently modifies cysteine residues on the luminal side of the H+/K(+)-ATPase of gastric parietal cells. Omeprazole and eight analogues were selected based on their chemical, electronic, and kinetic properties, and each was incubated with viable H. pylori in phosphate-buffered saline at pH 7.4 for 30 min, after which 100 mM urea was added and the amount of ammonia formed analyzed after a further 10 min. Inhibition between 0% and 100% at a 0.1 mM concentration was observed for the different analogues and could be expressed as a function of the pKa-value of the pyridine, the pKa-value of the benzimidazole, the overall lipophilicity, and, most importantly, the rate of sulfenamide formation, in a quantitative structure-activity relationship. The inhibition was potentiated by a lower pH (favoring the formation of the sulfenamide) but abolished in the presence of beta-mercaptoethanol (a scavenger of the sulfenamide). Structural analogues incapable of yielding the sulfenamide did not inhibit ammonia production. Treatment of Helicobacter felis-infected mice with 230 mumol/kg flurofamide b.i.d. for 4 weeks, known to potently inhibit urease activity in vivo, as a means of eradicating the infection, was tested and compared with the effect of 125 mumol/kg omeprazole b.i.d. for 4 weeks. Neither treatment proved efficacious.
PYRAZOLE-OXAZOLIDINONE COMPOUND FOR ANTI-HEPATITIS B VIRUS
申请人:Shanghai Zhimeng Biophama Co., Ltd.
公开号:US20190152963A1
公开(公告)日:2019-05-23
The present invention discloses a pyrazole-oxazolidinone compound having anti-hepatitis B virus activity, which has the structure of formula (I), wherein each variable is as defined herein.
Structure−Activity Relationship of 2-[[(2-Pyridyl)methyl]thio]-1<i>H</i>- benzimidazoles as Anti <i>Helicobacter pylori </i>Agents in Vitro and Evaluation of their in Vivo Efficacy
作者:Thomas C. Kühler、Marianne Swanson、Vladimir Shcherbuchin、Håkan Larsson、Björn Mellgård、Jan-Eric Sjöström
DOI:10.1021/jm970165r
日期:1998.5.1
A relationship between the structure of 21 2-[[(2-pyridyl)methyl]thio]-1H-benzimidazoles (6) and their anti Helicobacter pylori activity expressed as minimum bactericidal concentration (MBC) values is described. Observed MBCs ranged from 256 to 1 microg/mL. The structure-activity relationship (SAR) showed that larger and more lipophilic compounds, especially compounds with such substituents in the
A series of pleuromutilinderivativescontaining benzimidazole were designed, synthesized, and evaluated for their antibacterial activities against Methicillin-resistant Staphylococcus aureus (MRSA) in this study. The in vitro antibacterial activities of the synthesized derivatives against four strains of S. aureus (MRSA ATCC 43300, S. aureus ATCC 29213, S. aureus 144, and S. aureus AD3) were determined
Compounds effective in inhibiting replication of Hepatitis C virus (“HCV”) are described. This invention also relates to processes of making such compounds, compositions comprising such compounds, and methods of using such compounds to treat HCV infection.