- Synthetic (±)-axinellamines deficient in halogen
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Hiding in plain sight: Tailored synthetic dimers of the natural product dispacamide exist as a dynamic set of structural isomers. These materials isomerize readily to unveil a spirocyclic glycocyamidine from which ring systems common to complex pyrrole/imidazole alkaloids can be derived. Fully synthetic axinellamine congeners have been prepared in this way (see scheme), wherein a host of unusual and unanticipated reactions are employed. Copyright
- Ding, Hui,Roberts, Andrew G.,Harran, Patrick G.
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- 4-Alkyl-1,2,4-triazole-3-thione analogues as metallo-β-lactamase inhibitors
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In Gram-negative bacteria, the major mechanism of resistance to β-lactam antibiotics is the production of one or several β-lactamases (BLs), including the highly worrying carbapenemases. Whereas inhibitors of these enzymes were recently marketed, they only target serine-carbapenemases (e.g. KPC-type), and no clinically useful inhibitor is available yet to neutralize the class of metallo-β-lactamases (MBLs). We are developing compounds based on the 1,2,4-triazole-3-thione scaffold, which binds to the di-zinc catalytic site of MBLs in an original fashion, and we previously reported its promising potential to yield broad-spectrum inhibitors. However, up to now only moderate antibiotic potentiation could be observed in microbiological assays and further exploration was needed to improve outer membrane penetration. Here, we synthesized and characterized a series of compounds possessing a diversely functionalized alkyl chain at the 4-position of the heterocycle. We found that the presence of a carboxylic group at the extremity of an alkyl chain yielded potent inhibitors of VIM-type enzymes with Ki values in the μM to sub-μM range, and that this alkyl chain had to be longer or equal to a propyl chain. This result confirmed the importance of a carboxylic function on the 4-substituent of 1,2,4-triazole-3-thione heterocycle. As observed in previous series, active compounds also preferentially contained phenyl, 2-hydroxy-5-methoxyphenyl, naphth-2-yl or m-biphenyl at position 5. However, none efficiently inhibited NDM-1 or IMP-1. Microbiological study on VIM-2-producing E. coli strains and on VIM-1/VIM-4-producing multidrug-resistant K. pneumoniae clinical isolates gave promising results, suggesting that the 1,2,4-triazole-3-thione scaffold worth continuing exploration to further improve penetration. Finally, docking experiments were performed to study the binding mode of alkanoic analogues in the active site of VIM-2.
- Gavara, Laurent,Legru, Alice,Verdirosa, Federica,Sevaille, Laurent,Nauton, Lionel,Corsica, Giuseppina,Mercuri, Paola Sandra,Sannio, Filomena,Feller, Georges,Coulon, Rémi,De Luca, Filomena,Cerboni, Giulia,Tanfoni, Silvia,Chelini, Giulia,Galleni, Moreno,Docquier, Jean-Denis,Hernandez, Jean-Fran?ois
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supporting information
(2021/06/15)
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- Reinvestigation of the structure-activity relationships of isoniazid
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Isoniazid (INH) remains a cornerstone for treatment of drug susceptible tuberculosis (TB), yet the quantitative structure-activity relationships for INH are not well documented in the literature. In this paper, we have evaluated a systematic series of INH analogs against contemporary Mycobacterium tuberculosis strains from different lineages and a few non-tuberculous mycobacteria (NTM). Deletion of the pyridyl nitrogen atom, isomerization of the pyridine nitrogen to other positions, replacement of the pyridine ring with isosteric heterocycles, and modification of the hydrazide moiety of INH abolishes antitubercular activity. Similarly, substitution of the pyridine ring at the 3-position is not tolerated while substitution at the 2-position is permitted with 2-methyl-INH 9 displaying antimycobacterial activity comparable to INH. To assess the specific activity of this series of INH analogs against mycobacteria, we assayed them against a panel of gram-positive and gram-negative bacteria, as well as a few fungi. As expected INH and its analogs display a narrow spectrum of activity and are inactive against all non-mycobacterial strains evaluated, except for 4, which has modest inhibitory activity against Cryptococcus neoformans. Our findings provide an updated analysis of the structure-activity relationship of INH that we hope will serve as useful resource for the community.
- Hegde, Pooja,Boshoff, Helena I.M.,Rusman, Yudi,Aragaw, Wassihun Wedajo,Salomon, Christine E.,Dick, Thomas,Aldrich, Courtney C.
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- Discovery, synthesis and in combo studies of Schiff’s bases as promising dipeptidyl peptidase-IV inhibitors
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Abstract: Diabetes mellitus is a main global health apprehension. Macrovascular illnesses, neuropathy, retinopathy, and nephropathy are considered some of its severe hitches. Gliptins are a group of hypoglycemic agents that inhibit dipeptidyl peptidase-IV (DPP-IV) enzyme and support blood glucose-lowering effect of incretins. In the current research, synthesis, characterization, docking, and biological evaluation of fourteen Schiff’s bases 5a–f and 9a–h were carried out. Compound 9f revealed the best in vitro anti-DPP-IV activity of 35.7% inhibition at a concentration of 100?μM. Compounds 9c and 9f with the highest in vitro DPP-IV inhibition were subjected to the in vivo glucose-lowering test using vildagliptin as a positive inhibitor. Vildagliptin, 9c, and 9f showed significant reduction in the blood glucose levels of the treated mice after 30?min of glucose administration. Moreover, induced fit docking showed that these derivatives accommodated the enzyme binding site with comparable docking scores. Schiff’s bases can serve as promising lead for the development of new DPP-IV inhibitors. Graphical Abstract: [Figure not available: see fulltext.].
- Abu Khalaf, Reema,Awad, Maha,Al-Essa, Luay,Mefleh, Sara,Sabbah, Dima,Al-Shalabi, Eveen,Shabeeb, Ihsan
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- From indole to pyrrole, furan, thiophene and pyridine: Search for novel small molecule inhibitors of bacterial transcription initiation complex formation
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The search for small molecules capable of inhibiting transcription initiation in bacteria has resulted in the synthesis of N,N′-disubstituted hydrazines and imine-carbohydrazides comprised of indole, pyridine, pyrrole, furan and thiophene using the respec
- Thach, Oscar,Mielczarek, Marcin,Ma, Cong,Kutty, Samuel K.,Yang, Xiao,Black, David StC.,Griffith, Renate,Lewis, Peter J.,Kumar, Naresh
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p. 1171 - 1182
(2016/03/01)
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- LABELLED AND UN-LABELLED METHYL-PYRROLYL-OXADIAZOLYL-DIAZABICYCLONONANE DERIVATIVES AND THEIR MEDICAL USE
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The present invention relates to certain labelled or un-labelled pyrrolyl-oxadizolyl-diazabicyclononane derivatives and their medical use. Furthermore, the present invention relates to the use of said derivatives in their labelled form in diagnostic methods, in particular for in vivo receptor imaging (neuroimaging).
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Page/Page column 12
(2012/11/06)
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- DIAZABICYCLONONYL OXADIAZOLE COMPOUNDS AND THEIR USE AS NICOTINIC ACETYLCHOLINE RECEPTOR MODULATORS
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This invention relates to diazabicyclononyl oxadiazolyl derivatives, which are found to-be modulators of the nicotinic acetylcholine receptors. Due to their pharmacological profile the compounds of the invention may be useful for the treatment of diseases or disorders as diverse as those related to the cholinergic system of the central nervous system (CNS), the peripheral nervous system (PNS), diseases or disorders related to smooth muscle contraction, endocrine diseases or disorders, diseases or disorders related to neuro-degeneration, diseases or disorders related to inflammation, pain, and withdrawal symptoms caused by the termination of abuse of chemical substances. Ar1 represents a pyrrolyl group, optionally substituted with alkyl or halo-alkyl.
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Page/Page column 16
(2011/07/07)
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- Bishydrazide derivatives of isoindoline as simple anion receptors
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Isoindoline has been investigated as a scaffold for the construction of anion receptors. A family of bishydrazide derivatives of isoindoline has been synthesized, and the anion-binding properties of these receptors were investigated both in solution and in the solid state. Enhanced affinity toward halides has been observed for isoindoline-based ligands compared to analogous pyrroledicarboxyamides. However, in the case of highly basic anions, the anion binding is accompanied by partial deprotonation of the receptors, which also leads to the color changes of ligands' solutions.
- Dydio, Pawel,Zielinski, Tomasz,Jurczak, Janusz
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supporting information; experimental part
p. 1525 - 1530
(2009/09/06)
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