Designing analogs of ticlopidine, a wall teichoic acid inhibitor, to avoid formation of its oxidative metabolites
摘要:
The thienopyridine antiplatelet agent, ticlopidine and its analog, clopidogrel, have been shown to potentiate the action of beta-lactam antibiotics, reversing the methicillin-resistance phenotype of methicillin- resistant Staphylococcus aureus (MRSA), in vitro. Interestingly, these thienopyridines inhibit the action of TarO, the first enzyme in the synthesis of wall teichoic acid, an important cell wall polymer in Gram-positive bacteria. In the human body, both ticlopidine and clopidogrel undergo a rapid P450-dependent oxidation into their respective antiplatelet-active metabolites, resulting in very low plasma concentrations of intact drug. Herein, a series of analogs of ticlopidine and clopidogrel that would avoid oxidative metabolism were designed, prepared and evaluated as inhibitors of TarO. Specifically, we replaced the P450-labile thiophene ring of ticlopidine and clopidogrel to a more stable phenyl group to generate 2-(2-chlorobenzyl)-1,2,3,4-tetrahydro-isoquinoline) (6) and (2-chloro-phenyl)-(3,4-dihydro-1H-isoquinolin- 2-yl)-acetic acid methyl ester (22), respectively. The latter molecules displayed inhibitory activity against TarO and formed the basis of a library of analogs. Most synthesized compounds exhibited comparable efficacy to ticlopidine and clopidogrel. So far, it was introduction of a trifluoromethyl group to compound 6, to generate 2-(2-trifluoromethyl-benzyl)-1,2,3,4-tetrahydro-isoquinoline (13) that exhibited enhanced activity against TarO. Compound 13 represents a novel stable inhibitor of TarO with synergistic impact on b-lactam antibiotics against MRSA and low potential for P-450 metabolism. (C) 2013 Elsevier Ltd. All rights reserved.
Efficient Synthesis of <i>N</i>-Alkyl Tetrahydroisoquinolines by Reductive Amination
作者:Sukanta Bhattacharyya、Hephzibah Kumpaty
DOI:10.1055/s-2005-872081
日期:——
An expedient access to diverse N-alkyl 1,2,3,4-tetrahydroisoquinolines is reported by reductive amination of aldehydes and ketones with tetrahydroisoquinoline (THIQ) in the presence of Ti(Oi-Pr) 4 and NaBH 4 . The N-alkyl THIQ products were rapidly purified by flow-through catch and release technique using commercially available polymer-supported sulfonic acid, MP-TsOH columns.
Direct β-C(sp<sup>3</sup>)–H Functionalization of Aliphatic Amines to α,β-Unsaturated Imines, Aldehydes, and Chromenes
作者:Sumana Mandal、Sujit Mahato、Chandan K. Jana
DOI:10.1021/acs.orglett.5b01744
日期:2015.8.7
functionalization of aliphatic amine was developed. The method is based on a reaction that yields enamine directly from the corresponding aliphatic amine, which otherwise requires the aid of metallic reagent and/or external oxidant. The reaction is operationally simple, general, and highly efficient in functionalizing both cyclic and acyclic amines. Structurally diverse unsaturated imines were obtained from N-heterocycles
An antibacterial composition is provided including a combination of a β-lactam antibiotic that has a binding affinity for bacterial penicillin-binding protein 2; and a non-antibiotic compound which may be a thienopyridine or a non-thienopyridine compound. A method of treatment using the composition is also provided.
[EN] NOVEL ANTIBACTERIAL COMBINATION THERAPY<br/>[FR] NOUVEAU TRAITEMENT COMBINÉ ANTIBACTÉRIEN
申请人:UNIV MCMASTER
公开号:WO2012162814A1
公开(公告)日:2012-12-06
An antibacterial composition is provided including a combination of a β-lactam antibiotic that has a binding affinity for bacterial penicillin-binding protein 2; and a non-antibiotic compound which may be a thienopyridine or a non-thienopyridine compound. A method of treatment using the composition is also provided.