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Valentina Verdoliva Giuseppe Digilio Michele Saviano Stefania De Luca 《Molecules (Basel, Switzerland)》2021,26(20)
Aziridine derivatives involved in nucleophilic ring-opening reactions have attracted great interest, since they allow the preparation of biologically active molecules. A chemoselective and mild procedure to convert a peptide cysteine residue into lanthionine via S-alkylation on aziridine substrates is presented in this paper. The procedure relies on a post-synthetic protocol promoted by molecular sieves to prepare lanthionine-containing peptides and is assisted by microwave irradiation. In addition, it represents a valuable alternative to the stepwise approach, in which the lanthionine precursor is incorporated into peptides as a building block. 相似文献
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Michele Saviano Laura Zaccaro Angela Lombardi Carlo Pedone Benedetto Di Blasio Xicheng Sun Gian P. Lorenzi 《Journal of inclusion phenomena and macrocyclic chemistry》1994,18(1):27-36
An X-ray analysis of single crystals (from MeOH) of cyclo(-D-Leu-L-MeLeu-D-Leu-L-MeLeu-D-Leu-L-MeLeu-) has been carried out. The analysis reveals that the molecules of the cyclopeptide occur in the crystals with two slightly different, almost hexagonal backbone conformations of the -type, and that pairs of molecules with the same conformation interact through their nonmethylated face, forming dimeric units (units A and B) with six interannular H-bonds. This kind of pairing reproduces well that expected for a two-ring element in a stack of antiparalle-rings. The X-ray analysis has also revealed the presence in the A units of two water molecules, each at one of two equivalent sites located on the 3-fold axis of the units and equidistant from the center of gravity, and the presence in the B units of one water molecule at the center of the units. This provides experimental support for the idea that stacks of-rings can serve as molecular channels. 相似文献
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A Combined NMR and Computational Approach to Determine the RGDechi‐hCit‐αvβ3 Integrin Recognition Mode in Isolated Cell Membranes 下载免费PDF全文
Dr. Biancamaria Farina Dr. Ivan de Paola Dr. Luigi Russo Dr. Domenica Capasso Dr. Annamaria Liguoro Dr. Annarita Del Gatto Dr. Michele Saviano Prof. Paolo V. Pedone Dr. Sonia Di Gaetano Dr. Gaetano Malgieri Dr. Laura Zaccaro Prof. Roberto Fattorusso 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(2):681-693
The critical role of integrins in tumor progression and metastasis has stimulated intense efforts to identify pharmacological agents that can modulate integrin function. In recent years, αvβ3 and αvβ5 integrin antagonists were demonstrated to be effective in blocking tumor progression. RGDechi‐hCit, a chimeric peptide containing a cyclic RGD motif linked to an echistatin C‐terminal fragment, is able to recognize selectively αvβ3 integrin both in vitro and in vivo. High‐resolution molecular details of the selective αvβ3 recognition of the peptide are certainly required, nonetheless RGDechi‐hCit internalization limited the use of classical in cell NMR experiments. To overcome such limitations, we used WM266 isolated cellular membranes to accomplish a detailed NMR interaction study that, combined with a computational analysis, provides significant structural insights into αvβ3 molecular recognition by RGDechi‐hCit. Remarkably, on the basis of the identified molecular determinants, we design a RGDechi‐hCit mutant that is selective for αvβ5 integrin. 相似文献
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Diana Salazar Illera Surisetti Suresh Maria Moccia Gea Bellini Michele Saviano Mauro F.A. Adamo 《Tetrahedron letters》2012,53(14):1808-1811
We describe the development of an N-heterocyclic carbene catalysed homoenolate addition to 4-nitro-5-styrylisoxazoles to give substituted cyclopentanones with a unique substitution pattern and as single diastereoisomers. The synthetic utility of the cyclopentanones obtained was briefly explored through their conversion into α-fluorinated diketones and keto acids. 相似文献
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Dr. Carlo Diaferia Dr. Concetta Avitabile Dr. Marilisa Leone Enrico Gallo Dr. Michele Saviano Prof. Dr. Antonella Accardo Prof. Dr. Alessandra Romanelli 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(57):14307-14316
Peptides and nucleic acids can self-assemble to give supramolecular structures that find application in different fields, ranging from the delivery of drugs to the obtainment of materials endowed with optical properties. Forces that stabilize the “suprastructures” typically are hydrogen bonds or aromatic interactions; in case of nucleic acids, Watson-Crick pairing drives self-assembly while, in case of peptides, backbone hydrogen bonds and interactions between aromatic side chains trigger the formation of structures, such as nanotubes or ribbons. Molecules containing both aromatic peptides and nucleic acids could in principle exploit different forces to self-assemble. In this work we meant to investigate the self-assembly of mixed systems, with the aim to understand which forces play a major role and determine formation/structure of aggregates. We therefore synthesized conjugates of the peptide FF to the peptide nucleic acid dimer “gc” and characterized their aggregates by different spectroscopic techniques, including NMR, CD and fluorescence. 相似文献
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Hassan Rakhshandeh Hamed Rajabi Khasevan Anella Saviano Mohammad Reza Mahdinezhad Vafa Baradaran Rahimi Sajjad Ehtiati Leila Etemad Alireza Ebrahimzadeh-bideskan Francesco Maione Vahid Reza Askari 《Molecules (Basel, Switzerland)》2022,27(18)
Background: Type-one diabetes (T1D), a chronic autoimmune disease with marked inflammatory responses, is associated with infertility complications and implications. Based on the anti-diabetic, antioxidant, and anti-hyperlipidemic potential of Portulaca oleracea (PO), this study aimed to evaluate the protective effect of this plant extract on streptozotocin-induced type-I-diabetes-associated reproductive system dysfunction and inflammation. Methods: Male rats were randomly divided into four experimental groups: control, diabetic, and treatment/s (PO extract at 100 or 300 mg/kg/daily). Then food and water consumption, body, testis and epididymis weights, histopathological evaluation, seminiferous tubules diameter, sperm count and motility, glucose levels, sex hormones, and inflammatory and oxidative stress markers were evaluated. Results: Our results showed that streptozotocin-induced diabetes significantly increased food and water consumption; increased glucose, MDA, TGF-β1, and TNF-α levels; and decreased the seminiferous tubules diameter, sperm count and motility, levels of LH, testosterone, total thiol, VEGF, and SOD activity. Interestingly, PO extract (phytochemically characterized by using liquid chromatography–mass spectrometry to detect bioactive molecules) significantly ameliorated these parameters and histopathological indexes’ damage in rats. Conclusion. Even if more preclinical assessments are needed to better characterize the mechanism/s of action, the results of this study will pave the way for the rational use of PO on diabetic-associated clinical complications and implications. 相似文献
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Bonomo RP Di Blasio B Maccarrone G Pavone V Pedone C Rizzarelli E Saviano M Vecchio G 《Inorganic chemistry》1996,35(15):4497-4504
The ternary copper(II) complex of 6-deoxy-6-[(2-(4-imidazolyl)ethyl)amino]cyclomaltoheptaose (CDhm) and L-tryptophanate (L-TrpO(-)) was characterized by ESR and X-ray diffraction. The solid state structure of [Cu(CDhm)(L-TrpO)](+) shows that the aromatic side chain of TrpO(-) is outside the cavity and that the two amino nitrogen atoms, one from the histamine molecule and one from the amino acidate, are in a cis disposition. The two amino nitrogens, the imidazole nitrogen, and the carboxylate oxygen atoms form the base of a square pyramid, which surrounds the copper(II) ion, a water molecule occupying an apical position. Atomic distances suggest for this complex that pi-pi and d-pi interactions could occur in the solid state. Morover, the [Cu(CDhm)(L-TrpO)](+) has a self-assembled structure in which a CDhm molecule behaves as host and as guest. The imidazole and the indole ring are directed into the cavity of an adjacent CDhm molecule from the wider cyclodextrin rim, thus forming a polymeric column structure. ESR spectra were run on the copper(II) ternary complexes with L- or D-tryptophanate and L- or D-alaninate in frozen aqueous solution and on the former pair of enantiomers in the solid state, as well. While in the case of the ternary complex with L- or D-alaninate no differences are observed in their frozen solution spectra, in the case of complexes with TrpO(-) subtle differences are found. These differences, which disappear when excess methanol is used, are ascribed to the presence of weak forces, such as hydrophobic or d-pi interactions. 相似文献