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排序方式: 共有771条查询结果,搜索用时 31 毫秒
761.
762.
Erica Gazzillo Stefania Terracciano Dafne Ruggiero Marianna Potenza Maria Giovanna Chini Gianluigi Lauro Katrin Fischer Robert Klaus Hofstetter Assunta Giordano Oliver Werz Ines Bruno Giuseppe Bifulco 《Molecules (Basel, Switzerland)》2022,27(12)
The development of new bioactive compounds represents one of the main purposes of the drug discovery process. Various tools can be employed to identify new drug candidates against pharmacologically relevant biological targets, and the search for new approaches and methodologies often represents a critical issue. In this context, in silico drug repositioning procedures are required even more in order to re-evaluate compounds that already showed poor biological results against a specific biological target. 3D structure-based pharmacophoric models, usually built for specific targets to accelerate the identification of new promising compounds, can be employed for drug repositioning campaigns as well. In this work, an in-house library of 190 synthesized compounds was re-evaluated using a 3D structure-based pharmacophoric model developed on soluble epoxide hydrolase (sEH). Among the analyzed compounds, a small set of quinazolinedione-based molecules, originally selected from a virtual combinatorial library and showing poor results when preliminarily investigated against heat shock protein 90 (Hsp90), was successfully repositioned against sEH, accounting the related built 3D structure-based pharmacophoric model. The promising results here obtained highlight the reliability of this computational workflow for accelerating the drug discovery/repositioning processes. 相似文献
763.
Dr. Ana M. Ortuño Dr. Pablo Reiné Prof. Luis Álvarez de Cienfuegos Dr. Irene R. Márquez Dr. Wynand Dednam Prof. Enrico B. Lombardi Prof. Juan J. Palacios Dr. Edmund Leary Prof. Giovanna Longhi Prof. Vladimiro Mujica Dra. Alba Millán Dra. M. Teresa González Linda A. Zotti Dra. Delia Miguel Prof. Juan M. Cuerva 《Angewandte Chemie (International ed. in English)》2023,62(16):e202218640
We report on the chemical design of chiral molecular junctions with stress-dependent conductance, whose helicity is maintained during the stretching of a single molecule junction due to the stapling of both ends of the inner helix. In the reported compounds, different conductive pathways are observed, with clearly different conductance values and plateau-length distributions, attributed to different conformations of the helical structures. The large chiro-optical responses and the potential use of these molecules as unimolecular spin filters have been theoretically proved using state-of-the-art Density Functional Theory (DFT) calculations, including a fully ab-initio estimation of the CISS-originating spin polarization which is done, for the first time, for a realistic molecular system. 相似文献
764.
Francesco A. Bottino Giovanna Di Pasquale Antonino Pollicino Robert D. Short 《Macromolecular rapid communications》1995,16(11):799-806
The accelerated ageing of polystyrene by means of 2-(2-methoxy-5-methylphenyl)-2H-benzotriazole, under conditions reproducing the outdoor environment, was studied. The results show that this benzotriazole derivative appreciably accelerates the rate of photodegradation at the surface of polystyrene. 相似文献
765.
Matteo Tommasini Giovanna Longhi Sergio Abbate Giuseppe Zerbi 《Journal of Raman spectroscopy : JRS》2014,45(1):89-96
We review the theory for overtones and combinations in resonant Raman spectroscopy introduced by Nafie, Stein and Peticolas in 1971 on the basis of time‐ordered diagrams, and we apply it to β‐carotene with the support of density functional theory calculations. Comparison with experimental results obtained by Tasumi's group in 1994 is provided. The theory here presented allows a prompt evaluation of resonant Raman intensities with presently available quantum chemistry tools. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
766.
Guilherme B. Strapasson Eduarda de C. Flach Dr. Marcelo Assis Prof. Silma A. Corrêa Prof. Elson Longo Dr. Giovanna Machado Prof. Jacqueline F. L. Santos Prof. Daniel E. Weibel 《Chemphyschem》2023,24(21):e202300002
Environmentally friendly methods for silver nanoparticles (AgNPs) synthesis without the use of hazardous chemicals have recently drawn attention. In this work, AgNPs have been synthesized by microwave irradiation using only honey solutions or aqueous fresh pink radish extracts. The concentrations of honey, radish extract, AgNO3 and pH were varied. AgNPs presented mean sizes between 7.0 and 12.8 nm and were stable up to 120 days. The AgNPs were employed as co-catalyst (TiO2@AgNPs) to increase the hydrogen photogeneration under UV-vis and only visible light irradiation, when compared to pristine TiO2 NPs. The prepared photocatalyst also showed hydrogen generation under visible light. Additionally, AgNPs were used to assemble a nanoplasmonic biosensor for the biodetection of extremely low concentrations of streptavidin, owing to its specific binding to biotin. It is shown here that green AgNPs are versatile nanomaterials, thus being potential candidates for hydrogen photogeneration and biosensing applications. 相似文献
767.
Gaetano Giammona Giovanna Pitarresi Gennara Cavallaro Giuseppe Spadaro 《Macromolecular Symposia》1999,138(1):225-230
α,β-Poly(N-2-hydroxyethyl)-DL-aspartamide (PHEA) was derivatized with glycidyl methacrylate (GMA). Aqueous solutions of the obtained copolymer PHEA-GMA (PHG) were irradiated by gamma rays with a dose rate of 0.5 KGy/h and at zero°C in the presence or in the absence of N, N'-methylenebisacrylamide (BIS). New hydrogel systems were obtained and characterized by FT-IR analyses and swelling measurements in aqueous medium at different pH values. 相似文献
768.
Giacomo Facchin Mario Gleria Francesco Minto Roberta Bertani Massimo Guglielmi Giovanna Brusatin 《Macromolecular rapid communications》1995,16(3):211-217
In this paper we describe a method for the functionalization of catenapoly[bis(4-hydroxyphenoxy)-λ5-phosphazene] with diazonium salts to form new, deeply-coloured, phosphazene copolymers containing variable amounts of azo dyes attached to the polyphosphazene skeleton. The degree of functionalization in these substrates is regulated in order not to exceed 20% of the sites available in the pristine polyphosphazene and to maintain a high percentage of unreacted, free, hydroxy groups, in the final, coloured copolymers. These species are still very reactive and able to undergo further functionalization reactions. 相似文献
769.
Paolo Vacca Maria Grazia Maglione Carla Minarini Giovanna Salzillo Eugenio Amendola Dario Della Sala Alfredo Rubino 《Macromolecular Symposia》2005,228(1):263-272
In order to optimize polymer light emitting diode (PLED) performances, devices with holes injected through an Indium Tin Oxide (ITO) / Polyaniline (PANI) electrode into the polymer are much more efficient than devices fabricated with the anode made only by ITO. We demonstrated that by using doped PANI as hole injection layer in a polymer light emitting diode the manufacturing process can become simpler. Indeed, the pattern of conductive layer can be produced without ITO photolithography by UV exposition. As hole transporter layer, Poly(N-vinylcarbazole) (PVK) was spin coated over the doped PANI layer and a layer of tris (8-hydroxy) quinoline aluminum (Alq3) was then thermally evaporated so as to form the electron transport layer. To complete the device structure, Aluminum contacts were deposited onto the organic layers by vacuum evaporation at low pressure. The layers were characterized by X-ray small-angle diffraction, IR Raman and UV-Vis spectroscopies. Devices without PANI and with PANI as HIL were studied. 相似文献
770.