Vietnamese traditional medicine has utilised the roots of Buch.-Ham. ex D.
View Article and Find Full Text PDFTwelve compounds were isolated from aerial parts through phytochemical analysis and the genus is the first place where the compounds 4-6 and 11-12 have been found. Based on the ability to inhibit NO production in RAW264.7 cells, compound 2 has demonstrated the strongest anti-inflammatory activity with an IC of 7.
View Article and Find Full Text PDFPore space partition (PSP) is an effective materials design method for developing high-performance small-pore materials for storage and separation of gas molecules. The continued success of PSP depends on broad availability and judicious choice of pore-partition ligands and better understanding of each structural module on stability and sorption properties. Here, by using substructural bioisosteric strategy (sub-BIS), a dramatic expansion of pore-partitioned materials is targeted by using ditopic dipyridyl ligands with non-aromatic cores or extenders, as well as by expanding heterometallic clusters to uncommon nickel-vanadium and nickel-indium clusters rarely known before in porous materials.
View Article and Find Full Text PDFFlexi-MOFs are typically limited to low-connected (<9) frameworks. Here we report a platform-wide approach capable of creating a family of high-connected materials (collectively called CPM-220) that integrate exceptional framework flexibility with high rigidity. We show that the multi-module nature of the pore-space-partitioned (partitioned net) platform allows us to introduce flexibility as well as to simultaneously impose high rigidity in a tunable module-specific fashion.
View Article and Find Full Text PDFMetal-Organic Frameworks (MOFs) can deliver many advantages when acting as enzyme mimics to assist with signal amplification in molecular detection: they have abundant active catalytic sites per unit volume of the material; their structures and elemental compositions are highly tunable, and their high specific surface area and porous property can assist with target separation and enrichment. In the present work, we have demonstrated that, by adding the pore partition agent, 2,4,6-tris(4-pyridyl)pyridine (TPY) during synthesis of the bimetallic Fe/Co-MIL-88(NH) MOF to block the open metal sites, a highly porous MOF of Fe/Co-TPY-MIL-88(NH) can be produced. This material also exhibits high stability in basic solutions and biofluids and possesses high peroxidase-mimicking activity, which can be utilized to produce long-lasting chemiluminescence (CL) from luminol and HO.
View Article and Find Full Text PDFA new perspective is proposed in the design of pore-space-partitioned MOFs that is focused on ligand symmetry properties sub-divided here into three hierarchical levels: 1) overall ligand, 2) ligand substructure such as backbone or core, and 3) the substituent groups. Different combinations of the above symmetry properties exist. Given the close correlation between nature of chemical moiety and its symmetry, such a unique perspective into ligand symmetry and sub-symmetry in MOF design translates into the influences on MOF properties.
View Article and Find Full Text PDFPore space partitioning (PSP) is methodically suited for dramatically increasing the density of guest binding sites, leading to the partitioned acs (pacs) platform capable of record-high uptake for CO and small hydrocarbons such as CH. For gas separation, achieving high selectivity amid PSP-enabled high uptake offers an enticing prospect. Here we aim for high selectivity by introducing the bioisosteric (BIS) concept, a widely used drug design strategy, into the realm of pore-space-partitioned MOFs.
View Article and Find Full Text PDFWe report here a one-step method for synthesizing multi-component and in-situ-formed homochiral spiroborate-ester-based metal-organic framework CPM-B1. This unique material successfully integrates COF fragment spiroborate ester within the MOF and simultaneously incorporate homochirality and helicity. In addition, CPM-B1 is a rare example of framework materials that results from the cooperative assembly of three charge-complementary cations: +1 (lithium), +2 (cobalt), and +3 (boron).
View Article and Find Full Text PDFMetal-organic frameworks (MOFs) have many attractive features, including tunable composition, rigid structure, controllable pore size, and large specific surface area, and thus are highly applicable in molecular analysis. Depending on the MOF structure, a high number of unsaturated metal sites can be exposed to catalyze chemical reactions. In the present work, we report that using both Co(II) and Fe(III) to prepare the MIL-88(NH) MOF, we can produce the bimetallic MOF that can catalyze the conversion of 3,3',5,5″-tetramethylbenzidine (TMB) to a color product through a reaction with HO at a higher reaction rate than the monometallic Fe-MIL-88(NH).
View Article and Find Full Text PDFTwo new rod-packing metal-organic frameworks (RPMOF) are constructed by regulating the in situ formation of the capping agent. In CPM-s7, carboxylate linkers extend 1D manganese-oxide chains in four additional directions, forming 3D RPMOF. The substitution of Mn with a stronger Lewis acidic Co , leads to an acceleration of the hydrolysis-prone sulfonate linker, resulting in presence of sulfate ions to reduce two out of the four carboxylate-extending directions, and thus forming a new 2D rod-packing CPM-s8.
View Article and Find Full Text PDFTwo new phenolic glycosides, 4-(3-hydroxypropyl)-2,6-dimethoxyphenol D-apiofuranosyl-(1→6)-D-glucopyranoside (), -cinnamyl alcohol 9(6'D-apiofuranosyl)-D-glucopyranoside (), together with nine known phenolic glycosides () were isolated from the roots of . Their structures were determined by extensive analysis of HRESIMS and NMR spectral data, as well as by comparison of their spectral data (including CD spectra) with those reported in the literature. Compounds - and - inhibited NO production in LPS-activated RAW264.
View Article and Find Full Text PDFWe report here a strategy for making anionic pacs type porous materials by combining pore space partition with charge reallocation. The method uses the first negatively charged pore partition ligand (2,5,8-tri-(4-pyridyl)-1,3,4,6,7,9-hexaazaphenalene, H-tph) that simultaneously enables pore partition and charge reallocation. Over two dozen anionic pacs materials have been made to demonstrate their excellent chemical stability and a high degree of tunability.
View Article and Find Full Text PDFThe chemical composition and anti-inflammatory activity of the endemic were investigated for the first time in this study. A phytochemical fractionation of the methanol extract of resulted in the isolation of a new stilbene (bavienside A) and two new chalcone glycosides (baviensides B and C, ). Their structures were elucidated via the interpretation of NMR and HRESIMS spectroscopic data.
View Article and Find Full Text PDFState-of-the-art MOFs are generally known for chemical stability at one end of the pH scale (i.e., pH < 0 or pH > 14).
View Article and Find Full Text PDFACS Appl Mater Interfaces
November 2021
The development of effective propane (CH)-selective adsorbents for the purification of propylene (CH) from CH/CH mixture is a promising alternative to replace the energy-intensive cryogenic distillation. However, few materials possess the dual desirable features of propane selectivity and high uptake capacity. Here, we report a family of pore-space-partitioned crystalline porous materials (CPM) with remarkable CH uptake capacity (up to 10.
View Article and Find Full Text PDFFor rare-earth separation, selective crystallization into metal-organic frameworks (MOFs) offers new opportunities. Especially important is the development of MOF platforms with high selectivity toward target ions. Here we report a MOF platform (CPM-66) with low-coordination-number environment for rare-earth ions.
View Article and Find Full Text PDFIntroduction of pore partition agents into hexagonal channels of MIL-88 type (acs topology) endows materials with high tunability in gas sorption. Here, we report a strategy to partition acs framework into pacs (partitioned acs) crystalline porous materials (CPM). This strategy is based on insertion of in situ synthesized 4,4'-dipyridylsulfide (dps) ligands.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
September 2020
By introducing a compatible reducing agent (2-ethylimidazole) into a mono-micelle assembly process, we present a type of ordered mesoporous TiO microspheres that combines radially aligned mesostructure with Ti defects in mesoporous frameworks. Such reductant acts as a building block of mesostructured frameworks and reduces Ti in situ to generate defects during calcination, giving rise to the coexistence of bulk Ti defects and an ordered mesostructure. The mesoporous TiO has both excellent mesoporosity (a high surface area of 106 m g , a mean pore size of 18.
View Article and Find Full Text PDFAn ideal material for CH/CH separation would simultaneously have the highest CH uptake capacity and the highest CH/CH selectivity. But such material is elusive. A benchmark material for ethane-selective CH/CH separation is peroxo-functionalized MOF-74-Fe that exhibits the best known separation performance due to its high CH/CH selectivity (4.
View Article and Find Full Text PDFZeolitic imidazolate frameworks (ZIFs) are traditionally synthesized solvothermally by using cost- and waste-incurring organic solvents. Here, a direct synthesis method is reported for ZIF-8, ZIF-67, and their heterometallic versions from solid precursors only. This solvent-free crystallization method not only completely avoids organic solvents, but also provides an effective path for the synthesis of homogeneous mixed-metal ZIFs.
View Article and Find Full Text PDFBackground: Primary health care (PHC) is usually the initial point of contact for individuals seeking to access health care and providers of PHC play a crucial role in the healthcare model. However, few studies have assessed the knowledge, ability, and skills (capacity) of PHC providers in delivering care. This study aimed to identify the capacity of PHC providers in countries of the Southeast and East Asian Nursing Education and Research Network (SEANERN).
View Article and Find Full Text PDFThe family of viruses encompasses a group of pathogens with a zoonotic potential as observed from previous outbreaks of the severe acute respiratory syndrome coronavirus and Middle East respiratory syndrome coronavirus. Accordingly, it seems important to identify and document the coronaviruses in animal reservoirs, many of which are uncharacterized and potentially missed by more standard diagnostic assays. A combination of sensitive deep sequencing technology and computational algorithms is essential for virus surveillance, especially for characterizing novel- or distantly related virus strains.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
June 2018
Homochiral metal-organic frameworks (MOFs) are an important class of chiral solids with potential applications in chiral recognition; however, relatively few are available. Of great importance is the availability of low-cost, racemization-resistant, and versatile enantiopure building blocks. Among chiral building blocks, d-camphoric acid is highly prolific, yet, its trans-isomer, l-isocamphoric acid, has remained unknown in the entire field of solid-state materials.
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