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71.
A method for C-Br/C-H bis-phenylation of methyl 4-bromocrotonate via nickel-catalyzed cross-coupling reaction has been developed. This protocol involves commercially available catalyst components and furnishes a suitable doubly phenylated building block. 相似文献
72.
Andrea Ventrella Raffaella Verrone Francesco Longobardi Angela Agostiano Vincenzo Lippolis Michelangelo Pascale Chris M. Maragos Michael Appell Lucia Catucci 《Journal of inclusion phenomena and macrocyclic chemistry》2013,75(3-4):285-292
T-2 and HT-2 toxins are mycotoxins produced by several Fusarium species that are commonly found in various cereal grains, including oats, barley, wheat and maize. Intake estimates indicate that the presence of these mycotoxins in the diet can be of concern for public health. In this work, the inclusion processes occurring between fluorescent anthracene-derivatives of T-2 and HT-2 toxins and different cyclodextrin (CD) molecules were investigated in aqueous solutions by means of UV–Vis absorption, fluorescence emission and dynamic light scattering. Binding constant values and chemico-physical parameters were calculated. It was found that β-CDs give stronger inclusion reactions with both T-2 and HT-2 derivatives, as stated by important emission intensity increments. Such interactions were found to be fundamentally enthalpy-driven. Among β-CDs, the effect of the methylation at hydroxyl groups was tested: as a result, the di-methyl form of β-CD was found to induce the best fluorescence intensity enhancements. 相似文献
73.
JPC – Journal of Planar Chromatography – Modern TLC - This paper was aimed at analytical and antioxidant activity studies on a series of European beech (Fagus sylvatica L.) leaves... 相似文献
74.
75.
Human Y‐chromosome SNP characterization by multiplex amplified product‐length polymorphism analysis
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Laura Smeldy Jurado Medina Marina Muzzio Marisol Schwab María Leticia Bravi Costantino Guillermo Barreto Graciela Bailliet 《Electrophoresis》2014,35(17):2524-2527
We designed an allele‐specific amplification protocol to optimize Y‐chromosome SNP typing, which is an unavoidable step for defining the phylogenetic status of paternal lineages. It allows the simultaneous highly specific definition of up to six mutations in a single reaction by amplification fragment length polymorphism (AFLP) without the need of specialized equipment, at a considerably lower cost than that based on single‐base primer extension (SNaPshot?) technology or PCR‐RFLP systems, requiring as little as 0.5 ng DNA and compatible with the small fragments characteristic of low‐quality DNA. By designation of two primers recognizing the derived and ancestral state for each SNP, which can be differentiated by size by the addition of a noncomplementary nucleotide tail, we could define major Y clades E, F, K, R, Q, and subhaplogroups R1, R1a, R1b, R1b1b, R1b1c, J1, J2, G1, G2, I1, Q1a3, and Q1a3a1 through amplification fragments that ranged between 60 and 158bp. 相似文献
76.
Adil Mustafa Elisa Pedone Lucia Marucci Despina Moschou Mirella Di Lorenzo 《Electrophoresis》2022,43(3):501-508
Effective methods for rapid sorting of cells according to their viability are critical in T cells based therapies to prevent any risk to patients. In this context, we present a novel microfluidic device that continuously separates viable and non-viable T-cells according to their dielectric properties. A dielectrophoresis (DEP) force is generated by an array of castellated microelectrodes embedded into a microfluidic channel with a single inlet and two outlets; cells subjected to positive DEP forces are drawn toward the electrodes array and leave from the top outlet, those subjected to negative DEP forces are repelled away from the electrodes and leave from the bottom outlet. Computational fluid dynamics is used to predict the device separation efficacy, according to the applied alternative current (AC) frequency, at which the cells move from/to a negative/positive DEP region and the ionic strength of the suspension medium. The model is used to support the design of the operational conditions, confirming a separation efficiency, in terms of purity, of 96% under an applied AC frequency of 1.5 × 106 Hz and a flow rate of 20 μl/h. This work represents the first example of effective continuous sorting of viable and non-viable human T-cells in a single-inlet microfluidic chip, paving the way for lab-on-a-chip applications at the point of need. 相似文献
77.
Dr. Andrea Aloia Dr. Michele Casiello Prof. Lucia D'Accolti Dr. Caterina Fusco Prof. Angelo Nacci Dr. Antonio Monopoli 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(65):e202202350
A novel Pd-catalysed oxidative coupling between benzoic acids and vinylarenes or acrylates to furnish isocoumarins and phthalides is reported. The reaction proceeds smoothly in molten tetrabutylammonium acetate via a selective C−H bond activation, with very low percentage of ligand-free palladium acetate as the catalyst, under atmospheric pressure of oxygen. Sub-stoichiometric amount of copper acetate is also required as a reoxidant for the palladium. 相似文献
78.
Michele Tomasini Dr. Lucia Caporaso Jonathan Trouvé Dr. Jordi Poater Dr. Rafael Gramage-Doria Dr. Albert Poater 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(57):e202201970
Non-biological catalysts following the governing principles of enzymes are attractive systems to disclose unprecedented reactivities. Most of those existing catalysts feature an adaptable molecular recognition site for substrate binding that are prone to undergo conformational selection pathways. Herein, we present a non-biological catalyst that is able to bind substrates via the induced fit model according to in-depth computational calculations. The system, which is constituted by an inflexible substrate-recognition site derived from a zinc-porphyrin in the second coordination sphere, features destabilization of ground states as well as stabilization of transition states for the relevant iridium-catalyzed C−H bond borylation of pyridine. In addition, this catalyst appears to be most suited to tightly bind the transition state rather than the substrate. Besides these features, which are reminiscent of the action modes of enzymes, new elementary catalytic steps (i. e. C−B bond formation and catalyst regeneration) have been disclosed owing to the unique distortions encountered in the different intermediates and transition states. 相似文献
79.
Lucia De Rosa Rossella Di Stasi Alessandra Romanelli Luca Domenico DAndrea 《Molecules (Basel, Switzerland)》2021,26(12)
Although a plethora of chemistries have been developed to selectively decorate protein molecules, novel strategies continue to be reported with the final aim of improving selectivity and mildness of the reaction conditions, preserve protein integrity, and fulfill all the increasing requirements of the modern applications of protein conjugates. The targeting of the protein N-terminal alpha-amine group appears a convenient solution to the issue, emerging as a useful and unique reactive site universally present in each protein molecule. Herein, we provide an updated overview of the methodologies developed until today to afford the selective modification of proteins through the targeting of the N-terminal alpha-amine. Chemical and enzymatic strategies enabling the selective labeling of the protein N-terminal alpha-amine group are described. 相似文献
80.
Johura Ansary Francesca Giampieri Tamara Y. Forbes-Hernandez Lucia Regolo Denise Quinzi Santos Gracia Villar Eduardo Garcia Villena Kilian Tutusaus Pifarre Jos M. Alvarez-Suarez Maurizio Battino Danila Cianciosi 《Molecules (Basel, Switzerland)》2021,26(8)
In recent times, scientific attention has been paid to different foods and their bioactive components for the ability to inhibit the onset and progress of different types of cancer. Nigella sativa extract, powder and seed oil and its main components, thymoquinone and α-hederin, have showed potent anticancer and chemosensitizing effects against various types of cancer, such as liver, colon, breast, renal, cervical, lung, ovarian, pancreatic, prostate and skin tumors, through the modulation of various molecular signaling pathways. Herein, the purpose of this review was to highlight the anticancer activity of Nigella sativa and it constitutes, focusing on different in vitro, in vivo and clinical studies and projects, in order to underline their antiproliferative, proapoptotic, cytotoxic and antimetastatic effects. Particular attention has been also given to the synergistic effect of Nigella sativa and it constitutes with chemotherapeutic drugs, and to the synthesized analogs of thymoquinone that seem to enhance the chemo-sensitizing potential. This review could be a useful step towards new research on N. sativa and cancer, to include this plant in the dietary treatments in support to conventional therapies, for the best achievement of therapeutic goals. 相似文献