1,237 research outputs found
Switching on the activity of 1,5-diaryl-pyrrole derivatives against drug-resistant ESKAPE bacteria
No full textAntibiotic resistance represents a significant threat worldwide. There is an urgent need to discover structurally innovative antibacterial agents for which no pre-existing resistance is known.
With the aim to speed up the drug discovery process and to reduce the limitations of target-based high-through put screenings (HTS) we described the synthesis and biological evaluation of a novel series of 1,5-diphenylpyrroles active against a wide panel of ESKAPE bacteria. In particular, a subsequent structure-activity relationship (SAR) study revealed that the modification of the functional groups can switch the selectivity and the antimicrobial activity from mycobacteria to Gram positive and Gram negative bacteria [1,2].
The new compounds show high activity against both wild type and drug-resistant Gram positive and Gram negative bacteria at concentrations similar than levofloxacin.
Microbiology studies revealed that the plausible target of this class of compounds is the bacterial DNA gyrase, with the pyrrole derivatives displaying similar inhibitory activity to levofloxacin against the wild type enzyme and retaining activity against the fluoroquinolone-resistant enzyme.
References:
[1] Bhakta, S.; Manetti, F.; Castagnolo, D. et al (2016) Design and Synthesis of 1-((1,5-Bis(4-chlorophenyl)-2-methyl-1H-pyrrol-3-yl)methyl)-4-methylpiperazine (BM212) and N-Adamantan-2-yl-N′-((E)-3,7-dimethylocta-2,6-dienyl)ethane-1,2-diamine (SQ109) Pyrrole Hybrid Derivatives: Discovery of Potent Antitubercular Agents Effective against Multidrug-Resistant Mycobacteria. J. Med. Chem.59:2780-2793.
[2] Masci, D.; Hind, C.; K. Islam, M.; Toscani, A.; Clifford, M.; Coluccia, A.; Conforti, I.; Touitou, M.; Wei, X.; Memdouh, S.; La Regina, G.; Silvestri, R; Sutton, M.; Castagnolo, D. (2019) Switching on the activity of 1,5-diaryl-pyrrole derivatives against drug-resistant ESKAPE bacteria: structure-activity relationships and mode of action studies. Eur. J. Med. Chem. 178:500-514
Structural analyses of two heterologously expressed native and mutated low molecular weight glutenin subunits. In: . (vol. 295, pp. 316-319). ISBN: . : (UNITED KINGDOM).
No full textSTRUCTURAL ANALYSES OF TWO HETEROLOGOUSLY EXPRESSED NATIVE AND MUTATED LOW MOLECULAR WEIGHT GLUTENIN SUBUNITS
No full textAnhydrous Superprotonic Conductivity in the Zirconium Acid Triphosphate ZrH5(PO4)(3)
No full text: The development of solid-state proton conductors with high proton conductivity at low temperatures is crucial for the implementation of hydrogen-based technologies for portable and automotive applications. Here, we report on the discovery of a new crystalline metal acid triphosphate, ZrH5 (PO4 )3 (ZP3), which exhibits record-high proton conductivity of 0.5-3.1×10-2 S cm-1 in the range 25-110 °C in anhydrous conditions. This is the highest anhydrous proton conductivity ever reported in a crystalline solid proton conductor in the range 25-110 °C. Superprotonic conductivity in ZP3 is enabled by extended defective frustrated hydrogen bond chains, where the protons are dynamically disordered over two oxygen centers. The high proton conductivity and stability in anhydrous conditions make ZP3 an excellent candidate for innovative applications in fuel cells without the need for complex water management systems, and in other energy technologies requiring fast proton transfer
A history of the various approaches to the vases from the end of XVII century until the beginning of the XIX century
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Preparation and characterization of pillared alkanedioxy and polyethylenglycol derivatives of lamba-zirconium phosphate
No full textTemperature-independent sensors based on perovskite-type oxides
No full textThe need of energy security and environment sustainability drives toward the development of energy technology in order to enhance the performance of internal combustion engines. Gas sensors play a key role for controlling the fuel oxygen ratio and monitoring the pollution emissions. The perovskite-type oxides can be synthesized for an extremely wide variety of combinations of chemical elements, allowing to design materials with suitable properties for sensing application. Lanthanum strontium ferrites, such as La 0.7Sr0.3FeO3, are suitable oxygen sensing materials with temperature-independence conductivity, but they have low chemical stability under reducing conditions. The addition of aluminum into the perovskite structure improves the material properties in order to develop suitable oxygen sensing probes for lean burn engine control systems. Perovskite-type oxides with formula (La0.7Sr0.3FeO 3,)(AlxFe1-x)O3 was synthesized by the citrate-nitrate combustion synthesis method. XRD analyses, show that it was synthesized a phase-pure powder belonging to the perovskite structure. Aluminum affects both the unit cell parameters, by shrinking the unit cell, and the powder morphology, by promoting the synthesis of particles with small crystallite size and large specific surface area. The partial substitution of iron with aluminum improves the chemical stability under reducing gas conditions and modulates the oxygen sensitivity by affecting the relative amount of Fe4+ and Fe3+, as confirmed from TPR profiles. In the same time, the addition of aluminum does not affects the temperature-independent properties of lanthanum strontium ferrites. Indeed, the electrical measurements show that (La0.7Sr0.3)(AlxFe1-x)O3 perovskites have temperature-independence conductivity from 900 K. © 2014 AIP Publishing LLC
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