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71.
72.
Claudia Curcio Silvia Brugiapaglia Sara Bulfamante Laura Follia Paola Cappello Francesco Novelli 《Molecules (Basel, Switzerland)》2021,26(6)
Pancreatic ductal adenocarcinoma (PDA) is one of the most lethal forms of human cancer, characterized by unrestrained progression, invasiveness and treatment resistance. To date, there are limited curative options, with surgical resection as the only effective strategy, hence the urgent need to discover novel therapies. A platform of onco-immunology targets is represented by molecules that play a role in the reprogrammed cellular metabolism as one hallmark of cancer. Due to the hypoxic tumor microenvironment (TME), PDA cells display an altered glucose metabolism—resulting in its increased uptake—and a higher glycolytic rate, which leads to lactate accumulation and them acting as fuel for cancer cells. The consequent acidification of the TME results in immunosuppression, which impairs the antitumor immunity. This review analyzes the genetic background and the emerging glycolytic enzymes that are involved in tumor progression, development and metastasis, and how this represents feasible therapeutic targets to counteract PDA. In particular, as the overexpressed or mutated glycolytic enzymes stimulate both humoral and cellular immune responses, we will discuss their possible exploitation as immunological targets in anti-PDA therapeutic strategies. 相似文献
73.
Sara Gil-Guerrero Prof. Manuel Melle-Franco Prof. Ángeles Peña-Gallego Prof. Marcos Mandado 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(68):16138-16143
The Clar Goblet, the first radical bowtie nanographene proposed by Erich Clar nearly 50 years ago, was recently synthesized. Bowtie nanographenes present quasi-degenerate magnetic ground states, which make them so elusive as unique. A thorough analysis is presented of the spin-state energetics of Clar Goblet and bowtie nanographenes by a battery of existing and novel ab initio procedures ranging from density functional theory to complete active space Hamiltonians. With this, it was proven that π radicals of bowtie nanographenes sit on BP (Benzo[cd]Pyrene) moieties driven by their local aromaticity, a purely chemical concept, which confers global stability to the whole structure. Besides, a novel Pauli energy densities analysis provided a visual intuitive explanation for this preference. These findings allow envisioning that analogous bowtie nanographenes with arbitrary polyradical character are not only feasible at the molecular scale but will share Clar Goblet's peculiar properties. 相似文献
74.
Large‐Scale Synthesis of Enantiopure Molecular Cages: Chiroptical and Recognition Properties 下载免费PDF全文
Sara Lefevre Dawei Zhang Estelle Godart Marion Jean Dr. Nicolas Vanthuyne Jean‐Christophe Mulatier Dr. Jean‐Pierre Dutasta Dr. Laure Guy Prof. Alexandre Martinez 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(6):2068-2074
A convenient and efficient gram‐scale synthesis for enantiopure hemicryptophane–tren (tren=tris(2‐aminoethyl)amine) derivatives has been developed. The four‐step synthesis is based on the optical resolution of a key intermediate, cyclotriveratrylene, for which the energy barrier for racemization has been measured to ensure that no racemization occurs during the two last steps of the synthetic pathway. The assignments of the absolute configurations have been performed by electronic circular dichroism and the enantiopurity was determined by NMR spectroscopy in the presence of enantiopure camphor sulfonic acid. To highlight the interest of such compounds, the recognition of norephedrine neurotransmitter was investigated and showed a remarkable enantioselectivity towards the C3 symmetrical hosts. Finally, this highly modular synthetic pathway was used to provide eight enantiopure hemicryptophanes with different sizes, shapes, and functionalities. These results underline the high potential of this approach, which could lead to many applications in chiral recognition or asymmetric supramolecular catalysis. 相似文献
75.
A simple and efficient procedure has been developed for the synthesis of biologically relevant 2‐substituted benzimidazoles through a one‐pot condensation of o‐phenylenediamines with aryl aldehydes catalysed by iron oxide magnetic nanoparticles (Fe3O4 MNPs) in short reaction times with excellent yields. In the present study, Fe3O4 MNPs synthesized in a green manner using aqueous extract of white tea (Camelia sinensis) (Wt‐Fe3O4 MNPs) were applied as a magnetically separable heterogeneous nanocatalyst to synthesize 2‐(4‐chlorophenyl)‐1H–benzo[d]imidazole which has potential application in pharmacology and biological systems. Fourier transform infrared and NMR spectroscopies were used to characterize the 2‐(4‐chlorophenyl)‐1H–benzo[d]imidazole. In vitro cytotoxicity studies on MOLT‐4 cells showed a dose‐dependent toxicity with non‐toxic effect of 2‐(4‐chlorophenyl)‐1H–benzo[d]imidazole, up to a concentration of 0.147 µM. The green synthesized Wt‐Fe3O4 MNPs as recyclable nanocatalyst could be used for further research on the synthesis of therapeutic materials, particularly in nanomedicine, to assist in the treatment of cancer. 相似文献
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77.
Genesis Infante Assoc. Prof. Sara Eisler 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(65):16121-16126
Sequential anionic intramolecular cyclizations and modelling were used for the first time to access unusual fused heterocyclic frameworks in excellent yields. 5-Exo-dig cyclizations yielded isoindolinone motifs and a subsequent 6-exo- and 7-endo-dig cyclization was directed to provide either fused isoquinoline or azepine frameworks. Regioselectivities were controlled by exploiting stereoelectronic effects via nC−→π*(Ph) interactions, and modelling studies provided reaction scope. 相似文献
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79.
Maud Jenart Claude Niebel Jean-Yves Balandier Julie Leroy Alix Mignolet Sara Stas Antoine Van Vooren Jérôme Cornil Yves Henri Geerts 《Tetrahedron》2012,68(1):349-355
Two quaterthiophene-based dimers including an ethylene bridge have been designed and efficiently prepared; experimental and computational studies show a promising potential as semiconducting material with a charge transport of higher dimensionality compared to quaterthiophene. 相似文献