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Robert G. Surbella III Korey P. Carter Trevor D. Lohrey Dallas Reilly Mark Kalaj Bruce K. McNamara Jon Schwantes Rebecca J. Abergel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(61):13819-13825
A new uranyl containing metal–organic framework, RPL-1 : [(UO2)2(C28H18O8)] . H2O (RPL for Radiochemical Processing Laboratory), was prepared, structurally characterized, and the solid-state photoluminescence properties explored. Single crystal X-ray diffraction data reveals the structure of RPL - 1 consists of two crystallographically unique three dimensional, interpenetrating nets with a 4,3-connected tbo topology. Each net contains large pores with an average width of 22.8 Å and is formed from monomeric, hexagonal bipyramidal uranyl nodes that are linked via 1,2,4,5-tetrakis(4-carboxyphenyl)benzene (TCPB) ligands. The thermal and photophysical properties of RPL-1 were investigated using thermogravimetric analysis and absorbance, fluorescence, and lifetime spectroscopies. The material displays excellent thermal stability and temperature dependent uranyl and TCPB luminescence. The framework is stable in aqueous media and due to the large void space (constituting 76 % of the unit cell by volume) can sequester organic dyes, the uptake of which induces a visible change to the color of the material. 相似文献
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Dr. Lidia A. Maslovskaya Dr. Andrei I. Savchenko Prof. Elizabeth H. Krenske Dr. Sharon Chow Tina Holt Dr. Victoria A. Gordon Dr. Paul W. Reddell Carly J. Pierce Prof. Peter G. Parsons Prof. Glen M. Boyle Prof. Andrei G. Kutateladze Prof. Craig M. Williams 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(51):11862-11867
Structurally unique halimanes EBC-232 and EBC-323, isolated from the Australian rainforest plant Croton insularis, proved considerably difficult to elucidate. The two diastereomers, which consist an unusual oxo-6,7-spiro ring system fused to a dihydrofuran, were solved by unification and consultation of five in silico NMR elucidation and prediction methods [i.e., ACDLabs, olefin strain energy (OSE), DP4, DU8+ and TD DFT CD]. Structure elucidation challenges of this nature are prime test case examples for empowering future AI learning in structure elucidation. 相似文献
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Ana Salomé Pires João Batista Dina Murtinho Célia Nogueira Anna Karamysheva M. Luísa Ramos Bruce F. Milne Nuno Tiago Tavares José Gonçalves Ana Cristina Gonçalves Ana Margarida Abrantes Rui Soares Teresa Gonçalves Maria Filomena Botelho M. Elisa Silva Serra 《应用有机金属化学》2020,34(5):e5569
Platinum metal complexes are the most common chemotherapeutics currently used in cancer treatment. However, the frequent adverse effects, as well as acquired resistance by tumor cells, urge the development of effective alternatives. In the recent past, copper complexes with Schiff base ligands have emerged as good alternatives, showing interesting results. Accordingly, and in continuation of previous studies in this area, three new camphoric acid-derived halogenated salen ligands and their corresponding Cu (II) complexes were synthesized and their antitumor activity was evaluated in order to determine the influence of the type and number of halogens present (Br, Cl). The in vitro cytotoxic activity was screened against colorectal WiDr and LS1034 and against breast MCF-7 and HCC1806 cancer cell lines. The results proved the halogenated complexes to be very efficient, the tetrachlorinated Cu (II) complex being the most promising, presenting IC50 of 0.63–1.09 μM for the cell lines studied. The complex also shows selectivity to colorectal cancer cells compared to non-tumor colon cells. It is worth highlighting that the tetrachlorinated Cu (II) complex, our most efficient complex, shows a significantly more powerful antitumor effect than the reference drugs currently used in conventional chemotherapy. The halogenated salen and corresponding complexes were also screened for their antimicrobial activity against four bacterial species-Staphylococcus aureus, Enterococcus faecalis, Escherichia coli and Pseudomonas aeruginosa-and four fungal species-Candida albicans, Candida glabrata, Aspergillus fumigatus and Alternaria alternata. The compounds were found to exhibit moderate to strong antibacterial activity against the bacterial strains studied. NMR studies and theoretical calculations provided some insight into the structure of the ligands and copper complexes. Considering the results presented herein, our work validates the potential use of copper-based chemotherapeutics as alternatives for cancer treatment. 相似文献
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Single‐Site Zeolite‐Anchored Organoiridium Carbonyl Complexes: Characterization of Structure and Reactivity by Spectroscopy and Computational Chemistry 下载免费PDF全文
Claudia Martinez‐Macias Dr. Mingyang Chen Prof. David A. Dixon Prof. Bruce C. Gates 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(33):11825-11835
A family of HY zeolite‐supported cationic organoiridium carbonyl complexes was formed by reaction of Ir(CO)2(acac) (acac=acetylacetonate) to form supported Ir(CO)2 complexes, which were treated at 298 K and 1 atm with flowing gas‐phase reactants, including C2H4, H2, 12CO, 13CO, and D2O. Mass spectrometry was used to identify effluent gases, and infrared and X‐ray absorption spectroscopies were used to characterize the supported species, with the results bolstered by DFT calculations. Because the support is crystalline and presents a nearly uniform array of bonding sites for the iridium species, these were characterized by a high degree of uniformity, which allowed a precise determination of the species involved in the replacement, for example, of one CO ligand of each Ir(CO)2 complex with ethylene. The supported species include the following: Ir(CO)2, Ir(CO)(C2H4)2, Ir(CO)(C2H4), Ir(CO)(C2H5), and (tentatively) Ir(CO)(H). The data determine a reaction network involving all of these species. 相似文献
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