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941.
Raffaella Catalano Francesca Procopio Daniel Chavarria Sofia Benfeito Stefano Alcaro Fernanda Borges Francesco Ortuso 《Molecules (Basel, Switzerland)》2022,27(8)
Human monoamine oxidases (hMAOs) are well-established targets for the treatment of neurological disorders such as depression, Parkinson’s disease and Alzheimer’s disease. Despite the efforts carried out over the years, few selective and reversible MAO inhibitors are on the market. Thus, a continuous search for new compounds is needed. Herein, MAO inhibitors were searched among the non-chiral constituents of Bergamot Essential Oil (BEO) with the aid of computational tools. Accordingly, molecular modeling simulations were carried out on both hMAO-A and hMAO-B for the selected constituents. The theoretically predicted target recognition was then used to select the most promising compounds. Among the screened compounds, Bergamottin, a furocoumarin, showed selective hMAO-B inhibitory activity, fitting its active site well. Molecular dynamics simulations were used to deeply analyze the target recognition and to rationalize the selectivity preference. In agreement with the computational results, experimental studies confirmed both the hMAO inhibition properties of Bergamottin and its preference for the isoform B. 相似文献
942.
Annette Wagner Stefan Dussling Stefano Scansani Peter Bach Michael Ludwig Christof B. Steingass Frank Will Ralf Schweiggert 《Molecules (Basel, Switzerland)》2022,27(8)
In this work, two vintages (2019 and 2020) of red-fleshed ‘Weirouge’ apples were processed with the innovative spiral filter press technology to investigate juice production in an oxygen-reduced atmosphere. After pressing, a more brilliant red color and appreciably higher amounts of oxidation-sensitive constituents (ascorbic acid, anthocyanins, and colorless (poly)phenols) were seen in spiral filter pressed juices compared to those produced with conventional systems (horizontal filter press and decanter). In a subsequent stability study (24 weeks storage at 4, 20, and 37 °C), the color and phenolic compounds were monitored and differences in the juices produced with the different pressing-systems were widely maintained during the storage period. The analyses of the anthocyanins and colorless (poly)phenols were conducted by UHPLC-DAD-ESI-QTOF-HR-MS/MS and UHPLC-DAD. The spiral filter press emerged as a promising technology for the production of juices with a more attractive color and a better retention of oxidation-sensitive constituents during processing and storage compared to conventional juices. 相似文献
943.
Gabriele Albertin Stefano Antoniutti Sonia Pizzol 《Journal of organometallic chemistry》2004,689(9):1639-1647
Chloro-complexes [OsCl(N-N)P3]BPh4 (1, 2) [N-N=2,2′-bipyridine (bpy) and 1,10-phenanthroline (phen); P=P(OEt)3 and PPh(OEt)2] were prepared by allowing OsCl4(N-N) to react with zinc dust in the presence of phosphites. Treatment of the chloro-complexes 1, 2 with NaBH4 yielded, in the case of bpy, the hydride [OsH(bpy)P3]BPh4 (4) derivatives. Mono-phosphite [OsCl(bpy)2P]BPh4 (3) complexes were also prepared by reacting the [OsCl2(bpy)2]Cl compound with zinc dust in the presence of phosphite. Protonation reaction of the hydride [OsH(bpy)P3]+ (4) cations with Brønsted acid was studied and led to thermally unstable (above 0 °C) dihydrogen [Os(η2-H2)(bpy)P3]2+ (4*) derivatives. The presence of the H2 ligand is supported by variable-temperature NMR spectra and T1min measurements. Carbonyl [Os(CO)(bpy){P(OEt)3}3](BPh4)2 (5), nitrile [Os(CH3CN)(bpy){P(OEt)3}3](BPh4)2 (6), and hydrazine [Os(bpy)(NH2NH2){P(OEt)3}3](BPh4)2 (7) complexes were prepared by substituting the H2 ligand in the η2-H2 (4*) derivatives. Aryldiazene complex [Os(C6H5NNH)(bpy){P(OEt)3}3](BPh4)2 (8) was also obtained by allowing the hydride [OsH(bpy)P3]BPh4 to react with phenyldiazonium cation. 相似文献
944.
B. Doug Park Mainak Poddar Stefano Vidussi 《Transactions of the American Mathematical Society》2007,359(6):2651-2662
We construct an infinite family of homologous, non-isotopic, symplectic surfaces of any genus greater than one in a certain class of closed, simply connected, symplectic four-manifolds. Our construction is the first example of this phenomenon for surfaces of genus greater than one.
945.
Benoît Corretja Stefano Evangelisti Nicolas Suaud 《Journal of Molecular Structure》2008,863(1-3):9-15
Ab initio calculations on molecular structures composed of hexagonal rings of sp3-hybridated nitrogen atoms (the external nitrogen atoms being saturated with hydrogens) are presented. All the studied systems are local minima on the potential energy surface, and dissociate producing nitrogen dimer and ammonia in different proportions. A periodic Hartree–Fock study of the infinite layer is also presented, and it is shown that the molecular structural parameters quickly converge towards the infinite-system values. Accordingly to the computed dissociation energies, these systems have a very high energy content. 相似文献
946.
Stefano Vigni 《Journal of Number Theory》2008,128(7):2159-2184
If E is a non-isotrivial elliptic curve over a global function field F of odd characteristic we show that certain Mordell-Weil groups of E have 1-dimensional χ-eigenspace (with χ a complex ring class character) provided that the projection onto this eigenspace of a suitable Drinfeld-Heegner point is non-zero. This represents the analogue in the function field setting of a theorem for elliptic curves over Q due to Bertolini and Darmon, and at the same time is a generalization of the main result proved by Brown in his monograph on Heegner modules. As in the number field case, our proof employs Kolyvagin-type arguments, and the cohomological machinery is started up by the control on the Galois structure of the torsion of E provided by classical results of Igusa in positive characteristic. 相似文献
947.
Michele A. Forastiere Stefano Pelli Giancarlo C. Righini Massimo Guglielmi Alessandro Martucci Munir M. Ahmad Orla McCarthy Eric Yeatman Antonello Vannucci 《Fiber and Integrated Optics》2001,20(1):29-43
Sol-gel is one of the most attractive techniques for production of silica-on-silicon integrated optical devices. In fact, it combines low cost with flexibility and ease of doping; thus, nonlinear and active compounds can be effectively included in the silica matrix. Here, the feasibility of applying the sol-gel technique to the realization of an erbium-doped optical amplifier is reported on, operating in the third telecommunication window. In particular, the development of an optimum strategy for the design and fabrication of a guiding structure in the strip-loaded configuration is described. Design optimization results, as well as fabrication results and measured characteristics, are described and discussed. 相似文献
948.
Roee Engelberg Jochen Knemann Stefano Leonardi Joseph Naor 《Journal of Discrete Algorithms》2007,5(2):262-279
We study budgeted variants of classical cut problems: the Multiway Cut problem, the Multicut problem, and the k-Cut problem, and provide approximation algorithms for these problems. Specifically, for the budgeted multiway cut and the k-cut problems we provide constant factor approximation algorithms. We show that the budgeted multicut problem is at least as hard to approximate as the sparsest cut problem, and we provide a bi-criteria approximation algorithm for it. 相似文献
949.
Polyleucines of various lengths act as enantioselective catalysts in the aldol condensation between cyclohexanone and various aromatic aldehydes. Polyleucine and other polyamino acids behave as synthetic enzymes in the epoxidation of chalcone and other electron-deficient alkenes. Both reactions are of considerable prebiotic significance. 相似文献
950.
Stefano Cicchi Dr. Pierangelo Fabbrizzi Dr. Giacomo Ghini Dr. Alberto Brandi Prof. Paolo Foggi Prof. Agnese Marcelli Dr. Roberto Righini Prof. Chiara Botta Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(3):754-764
A series of dendrimeric compounds bearing pyrene units were synthesized to afford light‐harvesting antennae based on the formation of intramolecular excimers. The synthetic plan profited from the efficiency of the Huisgen reaction, the 1,3‐dipolar cycloaddition of azides and terminal alkynes, which allowed ready assembly of the different building blocks. The three molecular antennae obtained, of increasing generation, revealed efficient energy transfer both in solution and in the solid state. 相似文献