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排序方式: 共有881条查询结果,搜索用时 15 毫秒
1.
Dr. Andy Hernández Montoto Dr. Antoni Llopis-Lorente Mónica Gorbe José M. Terrés Dr. Roberto Cao-Milán Dr. Borja Díaz de Greñu Dr. María Alfonso Dr. Javier Ibañez Prof. María D. Marcos Dr. Mar Orzáez Dr. Reynaldo Villalonga Prof. Ramón Martínez-Máñez Dr. Félix Sancenón 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(36):8471-8478
Janus gold nanostar–mesoporous silica nanoparticle ( AuNSt–MSNP ) nanodevices able to release an entrapped payload upon irradiation with near infrared (NIR) light were prepared and characterized. The AuNSt surface was functionalized with a thiolated photolabile molecule ( 5 ), whereas the mesoporous silica face was loaded with a model drug (doxorubicin) and capped with proton-responsive benzimidazole-β-cyclodextrin supramolecular gatekeepers ( N 1 ). Upon irradiation with NIR-light, the photolabile compound 5 photodissociated, resulting in the formation of succinic acid, which induced the opening of the gatekeeper and cargo delivery. In the overall mechanism, the gold surface acts as a photochemical transducer capable of transforming the NIR-light input into a chemical messenger (succinic acid) that opens the supramolecular nanovalve. The prepared hybrid nanoparticles were non-cytotoxic to HeLa cells, until they were irradiated with a NIR laser, which led to intracellular doxorubicin release and hyperthermia. This induced a remarkable reduction in HeLa cells viability. 相似文献
2.
Thioetherphenolate group 4 metal complexes in the ring opening polymerization of rac‐β‐Butyrolactone 下载免费PDF全文
Ermanno Luciano Antonio Buonerba Alfonso Grassi Stefano Milione Carmine Capacchione 《Journal of polymer science. Part A, Polymer chemistry》2016,54(19):3132-3139
Group 4 complexes 1 – 3 [ 1 = (t‐BuOS)2Ti(O‐i‐Pr)2; 2 = (t‐BuOS)2Zr(O‐t‐Bu)2; 3 = (t‐BuOS)2Hf(O‐t‐Bu)2] supported by two phenolate bidentate ligands (t‐BuOS‐H = 4,6‐di‐tert‐butyl‐2‐phenylsulfanylphenol) promote the well‐controlled ring opening polymerization of rac‐β‐butyrolactone. In presence of isopropanol, low dispersities and molecular weights proportional to the equivalents of isopropanol are achieved. Moreover, the zirconium complex is effective in the copolymerization of rac‐β‐butyrolactone with rac‐lactide. The 13 C nuclear magnetic resonance analysis revealed that the obtained copolymers have a tapered diblock microstructure consisting of an initial block composed of lactide sequences and a terminal block composed of butyrolactone sequences. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 3132–3139 相似文献
3.
Dr. Francesco Della Monica Dr. Veronica Paradiso Prof. Dr. Alfonso Grassi Dr. Stefano Milione Prof. Dr. Luigi Cavallo Prof. Dr. Carmine Capacchione 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(24):5347-5353
A new chromium(III) complex, bearing a bis-thioether-diphenolate [OSSO]-type ligand, was found to be an efficient catalyst in the copolymerization of CO2 and epoxides to achieve poly(propylene carbonate), poly(cyclohexene carbonate), poly(hexene carbonate) and poly(styrene carbonate), as well as poly(propylene carbonate)(cyclohexene carbonate) and poly(propylene carbonate)(hexene carbonate) terpolymers. 相似文献
4.
Gema Vivo-Llorca Vicente Candela-Noguera Dr. María Alfonso Dr. Alba García-Fernández Prof. Mar Orzáez Dr. Félix Sancenón Prof. Ramón Martínez-Máñez 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(69):16318-16327
Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype. In the last years, navitoclax has emerged as a possible treatment for TNBC. Nevertheless, rapid navitoclax resistance onset has been observed thorough Mcl-1 overexpression. As a strategy to overcome Mcl-1-mediated resistance, herein we present a controlled drug co-delivery system based on mesoporous silica nanoparticles (MSNs) targeted to TNBC cells. The nanocarrier is loaded with navitoclax and the Mcl-1 inhibitor S63845 and capped with a MUC1-targeting aptamer ( apMUC1-MSNs(Nav/S63845) ). The apMUC1-capped nanoparticles effectively target TNBC cell lines and successfully induce apoptosis, overcoming navitoclax resistance. Moreover, navitoclax encapsulation protects platelets against apoptosis. These results point apMUC1-gated MSNs as suitable BH3 mimetics nanocarriers in the targeted treatment of MUC1-expressing TNBC. 相似文献
5.
Dr. Pilar Ventosa‐Andrés Dr. Agustina La‐Venia Dr. Carlos Alfonso Barea Ripoll Dr. Ludmila Hradilová Dr. Viktor Krchňák 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(37):13112-13119
Herein, we describe the synthesis of molecular scaffolds consisting of medium‐sized fused heterocycles using amino acids, which are some of the most useful building blocks used by nature as well as chemists to create structural diversity. The acyclic precursors were assembled by using traditional Merrifield solid‐phase peptide synthesis, and cyclization was carried out through acid‐mediated tandem endocyclic N‐acyliminium ion formation, followed by nucleophilic addition with internal nucleophiles. The synthesis of molecular scaffolds consisting of seven‐, eight‐, and nine‐membered rings proceeded with full stereocontrol of the newly generated stereogenic center in most cases. 相似文献
6.
Reactivity with Amines of Bis(cyanamide) and Bis(cyanoguanidine) Complexes of the Iron Triad 下载免费PDF全文
Treatment of bis(cyanamide) [M(N≡CNEt2)2L4](BPh4)2 and bis(cyanoguanidine) [M{N≡CN(H)C(NH2)=NH}2L4](BPh4)2 complexes [M = Fe, Ru, Os; L = P(OEt)3] with an excess of amine RNH2 (R = nPr, iPr) affords mixed‐ligand complexes with cyanamide and amine [M(NH2R)(N≡CNEt2)L4](BPh4)2 ( 1a – 5a ) and [M(NH2R){N≡CN(H)C(NH2)=NH}L4](BPh4)2 ( 1b , 2b ). The complexes were characterized by spectroscopy and X‐ray crystal structure determination of [M(NH2iPr)(N≡CNEt2){P(OEt)3}4](BPh4)2 [M = Ru ( 3a ), Os ( 5a )]. 相似文献
7.
Aurora Molinari Alfonso Oliva Marlene Arismendi Elizabeth Imbarack Cristian Glvez Javier Maldonado Arturo San Feliciano 《Journal of heterocyclic chemistry》2015,52(2):620-622
New fused pyrazolo‐1,4‐naphthoquinones were prepared from the reaction of hydrazines with 6‐(4‐methyl‐3‐pentenyl)‐1,4‐naphthoquinone. The reaction was extended to hydroxylamine to afford the corresponding isoxazolo‐1,4‐napthoquinone compound. 相似文献
8.
Potential of prodendronic polyamines with modulated segmental charge density as novel coating for fast and efficient analysis of peptides and basic proteins by CE and CE‐MS 下载免费PDF全文
Tanize Acunha Clara Ibáñez María Isabel Pascual Reguera Mariagiovanna Sarò Rodrigo Navarro Juan Alfonso Redondo Helmut Reinecke Alberto Gallardo Carolina Simó Alejandro Cifuentes 《Electrophoresis》2015,36(14):1564-1571
In this work, the suitability of a new polymer family has been investigated as capillary coatings for the analysis of peptides and basic proteins by CE. This polymer family has been designed to minimize or completely prevent protein–capillary wall interactions and to modify the EOF. These coating materials are linear polymeric chains bearing as side cationizable moiety a dentronic triamine derived from N,N,N’,N’‐tetraethyldiethylenetriamine (TEDETA), which is linked to the backbone through a spacer (unit labeled as TEDETAMA). Four different polymers have been prepared and evaluated: a homopolymer which comprised only of those cationizable repetitive units of TEDETAMA, and three copolymers that randomly incorporate TEDETAMA together with neutral hydrosoluble units of N‐(2‐hydroxypropyl) methacrylamide (HPMA) at different molar percentages (25:75, 50:50 and 75:25). It has been demonstrated that the composition of the copolymers influences the EOF and therefore the separation of the investigated biopolymers. Among the novel polymers studied, poly‐(TEDETAMA‐co‐HPMA) 50:50 copolymer was successfully applied as coating material of the inner capillary surface in CE‐UV and CE‐MS, providing EOF reversing together with fast and efficient baseline separation of peptides and basic proteins. Finally, the feasibility of the polymer‐coated capillary was shown through the analysis of lysozyme in a cheese sample. 相似文献
9.
Alejandra Medrano-Banda Dr. Alfonso Crespo-Yapur Dr. Miguel Ángel Velasco-Soto Dr. Marcelo Videa 《ChemistryOpen》2022,11(2):e202100241
The synthesis of hybrid platinum materials is fundamental to enable alkaline water electrolysis for cost-effective H2 generation. In this work, we have used a galvanostatic method to co-deposit PtNi films onto polycrystalline gold. The surface concentrations of Ni (ΓNi) and Pt (ΓPt) were calculated from electrochemical measurements; the ΓPt/ΓNi ratio and electrocatalytic activity of these materials towards hydrogen evolution reaction (HER) in 1 M KOH show a strong dependence on the current density pulse applied during the electrodeposition. Analysis of the Tafel parameters hints that, on these deposits, HER proceeds through a Volmer-Heyrovsky mechanism. The galvanostatically deposited PtNi layers present a high current output per Pt gram, 3199 A gPt−1, which is significantly larger compared to other PtNi-based materials obtained by more extended and more complex synthesis methods. 相似文献
10.
In this paper, we introduce the notion of slant submanifolds of a para-Hermitian manifold. We study their first properties and present a whole gallery of examples. 相似文献