Development of novel antibacterial agents against methicillin-resistant Staphylococcus aureus
摘要:
Methicillin-resistant Staphylococcus aureus (MRSA) poses a serious threat to public health because of its resistance to multiple antibiotics most commonly used to treat infection. In this study, we report the unique ability of the cyclooxygenase-2 (COX-2) inhibitor celecoxib to kill Staphylococcus aureus and MRSA with modest potency. We hypothesize that the anti-Staphylococcus activity of celecoxib could be pharmacologically exploited to develop novel anti-MRSA agents with a distinct mechanism. Examination of an in-house, celecoxib-based focused compound library in conjunction with structural modifications led to the identification of compound 46 as the lead agent with high antibacterial potency against a panel of Staphylococcus pathogens and different strains of MRSA. Moreover, this killing effect is bacteria-specific, as human cancer cells are resistant to 46. In addition, a single intraperitoneal administration of compound 46 at 30 mg/kg improved the survival of MRSA-infected C57BL/6 mice. In light of its high potency in eradicating MRSA in vitro and its in vivo activity, compound 46 and its analogues warrant continued preclinical development as a potential therapeutic intervention against MRSA. (C) 2012 Elsevier Ltd. All rights reserved.
Oligonucleotides having alkylphosphonate linkages and methods for their preparation
申请人:Isis Pharmaceuticals, Inc.
公开号:US20030078414A1
公开(公告)日:2003-04-24
The present invention provides alkylphosphonate dimers and oligonucleotides prepared therefrom. The invention further provides novel methods for the preparation of these alkylphosphonate dimers. Methods for the preparation of substantially diastereomerically pure alkylphosphonate dimers are also provided.
An unconventional [1 + 1 + 1 + 1 + 1 + 1] annulation process was developed for the construction of β,β-dithioketones by merging C–C and C–S bond cleavage. In this reaction, rongalite concurrently served as triple C1 units, dual sulfur(II) synthons, and a reductant for the first time. Mechanism investigation indicated that the reaction involved the self-mediated valence state change of rongalite. By