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A new microporous Zn(ii)-based MOF 1 has been successfully synthesized by utilizing both amino- and nitro-functionalized ligands. Gas sorption explorations reveal that the activated sample exhibits significant C2H2 uptakes and selective capture from CO2.

A new hybrid uranyl-silicotungstate (U3) was synthesized and characterized. U3 contains two kinds of Keggin-type building units and shows good catalytic activity in the synthesis of dihydropyrimidin-2(1H)-ones from aldehydes, acetoacetates, and urea.

Buccal midazolam treatment is licensed in the European Union for prolonged acute convulsive seizures in children and adolescents, but the buccal pathway is often hampered by jaw clenching, hypersalivation, or uncontrolled swallowing. Midazolam formulations that are more secure, reliable, and faster for use are needed in the acute setting. Pharmacokinetics and comparative bioavailability of intranasally administered midazolam and two midazolam intravenous solutions administered buccally or intravenously in healthy adults were evaluated.In this phase 1, open-label, randomized, single-dose, three-period, three-sequence crossover study, 12 healthy adults (19-41 years) were randomly assigned to receive 2.5 mg midazolam intranasally; 2.5 mg midazolam intravenously; 2.5 mg midazolam buccally. Blood samples were collected for 10 h post dose to determine pharmacokinetic profiles. Adverse events and vital signs were recorded.Intranasal administration of 2.5 mg midazolam demonstrated a more rapid median time to CIntranasal administration of midazolam may be a preferable alternative to the currently approve buccal midazolam treatment for prolonged acute convulsive seizures in children and adolescents.This study is registered at the Chinese Clinical Trial [ http://www.chictr.org.cn ] (ChiCTR2000032595) on 3 May, 2020.

A facile strategy was developed for the preparation of magnetically recyclable Co2P nanosheets with efficient catalytic activity for NaBH4 hydrolysis.

This review exhibits a comprehensive summary of uranium-containing polyoxometalates, including synthesis and structures, characterizations, properties, and applications. The development prospects and future directions are also elucidated.

Background Ixodes granulatus is of significant research value as the primary vector of Lyme disease in Asia, yet the bacterial community structure and diversity carried by these ticks have not been reported so far. Part of bacteria in ticks can affect tick development and the transmission of tick-borne pathogens. With the emergence of new pathogens, it is necessary to identify the bacterial microbiome carried by I. granulatus. Methods Ixodes granulatus were collected from rodent animals in the Binchuan, China. The bacterial DNA was extracted from non-engorged adult female I. granulatus. Sequencing of the V3-V4 regions of the 16S rRNA genes was performed using the Illumina NovaSeq sequencing platform. Initial data was assembled in FLASH, QIIME, and UCHIME algorithm. Uparse and MUSCLE software were used to annotate and analyze the effective data. Result The predominant phyla in all samples were Firmicutes, Proteobacteria, Actinobacteria, and Spirochaetota. The major genera were Spiroplasma, Staphylococcus, Candidatus-Lariskella, Corynebacterium, Ralstonia, Borreliella (Borrelia), Vibrio, Bacillus, and Listeria. Staphylococcus xylosus, Ralstonia pickettii, Corynebacterium mastitidis, Bryopsis hypnoides, and Vibrio metschnikovii were dominant bacterial species. The results demonstrated that there were discrepancies in bacterial microbiome richness and diversity among different individual ticks of the same species, and found a large number of pathogenic bacteria and opportunistic pathogens, yet Coxiella and Rickettsia were not detected. Conclusion The results presented here speculate that Spiroplasma is the endosymbiont of I. granulatus and competitively inhibits Borrelia. Our study suggested that Binchuan is at risk of Lyme disease transmission and needs to be taken seriously. These findings may serve fundamental knowledge for developing novel strategies to control ticks and their transmission of diseases.

Introduction HS-10234, a novel prodrug of tenofovir (TFV), functions by inhibiting nucleotide reverse transcriptase against retroviral infections including hepatitis B virus and human immunodeficiency virus (HIV). As it is a possible substitute for TFV co-administration with emtricitabine, determining the drug-drug interactions (DDI) between HS-10234 and emtricitabine therapy will be helpful for researchers to design and conduct future phase II/III studies and merits careful examination in the era of evolving new combination antiretroviral therapy regimens. Methods We conducted an open-label, two-sequence, two-period, self-controlled phase I trial that enrolled 36 healthy volunteers randomized into two groups (group 1 and group 2). Eighteen subjects in group 1 were orally administered HS-10234 at a 25-mg daily dose for 7 days during period 1 (D1-D7) followed by co-administration of emtricitabine at a 200-mg dose once daily (QD) for 7 additional days during period 2 (D8-D14). Participants in group 2 were orally administered emtricitabine 200 mg QD for 7 days during period 1 (D1-D7) and then co-administered HS-10234 25 mg QD for 7 additional days during period 2 (D8-D14). Pharmacokinetics (PK) of HS-10234 and emtricitabine were characterized when administered alone and in combination. The concentrations of HS-10234 and its metabolites TFV and emtricitabine were determined using high performance liquid chromatography-mass spectrometry (HPLC-MS)/MS. Peripheral blood monocyte cells (PBMCs) were isolated for detection of intracellular concentrations of HS-10234's active metabolite, intracellular tenofovir diphosphate (TFV-DP) pre-dose and 2, 4, 8, 12 and 24 h post-dose on D7 and D14 in group 1. WinNonlin software was used to calculate PK parameters. Results After multiple-dose administration of HS-10234 with emtricitabine, the AUC0-tau of HS-10234 and TFV-DP was 1.327- and 1.403-fold higher than that with HS-10234 administration alone. The Cmax and AUC0-tau were increased 1.120- and 1.077-fold compared to emtricitabine administration alone. Co-administration of HS-10234 with oral emtricitabine was well tolerated. No serious adverse events were observed. Conclusions Although a slightly increased steady-state PK exposure of HS-10234 and TFV-DP was observed with co-administration of oral HS-10234 with emtricitabine, these changes were not considered clinically relevant. Thus, dose adjustments are not recommended for HS-10234 combination with emtricitabine. Trial registration NCT04477096, July 20, 2020.

A novel U(VI)-containing polytungstate (U-POW) tetramer, {K

The reasonable design and preparation of cheap, Earth-abundant, efficient, and durable heterogeneous electrocatalytic materials are a probable solution to the key problems of energy shortages and e...

A new porous metal–organic framework (MOF) {[Cd(Hbptc)]·H2O}n (Cdbptc) was assembled by Cd(II) ions and a rigid (1,1′-biphenyl)-2,4,6-tricarboxylic acid (H3bptc) ligand via a solvothermal method. C...

Though N-heterocyclic carbenes (NHCs) have emerged as diverse and powerful discrete functional molecules in pharmaceutics, nanotechnology, and catalysis over decades, the heterogenization of NHCs and their precursors for broader applications in porous materials, like metal–organic frameworks (MOFs), porous coordination polymers (PCPs), covalent-organic frameworks (COFs), porous organic polymers (POPs), and porous organometallic cages (POMCs) was not extensively studied until the last ten years. By de novo or post-synthetic modification (PSM) methods, myriads of NHCs and their precursors containing building blocks were designed and integrated into MOFs, PCPs, COFs, POPs and POMCs to form various structures and porosities. Functionalisation with NHCs and their precursors significantly expands the scope of the potential applications of porous materials by tuning the pore surface chemical/physical properties, providing active sites for binding guest molecules and substrates and realizing recyclability. In this review, we summarise and discuss the recent progress on the synthetic methods, structural features, and promising applications of NHCs and their precursors in functionalised porous materials. At the end, a brief perspective on the encouraging future prospects and challenges in this contemporary field is presented. This review will serve as a guide for researchers to design and synthesize more novel porous materials functionalised with NHCs and their precursors.

Two new three-dimensional (3D) metal–organic frameworks (MOFs), namely {[Cu2(L)(4,4′-bipy)(OH)]·H2O}n (1) and {[Mn3(L)2(4,4′-bipy)(DMA)2]·H2O}n (2), were constructed by a newly synthesized thioether carboxylic acid ligand 5-((formic acid-3-sulfur)methyl)isophthalic acid (H3L) and 4,4′-bipyridine (4,4′-bipy). Thioether bonds in H3L can rotate freely in space, which are conducive in constructing MOFs with rich and stable structures. Simultaneously, the uncoordinated sulfur atoms affect the polarity of the framework and play an important role in adsorption. Gas adsorption results indicated that 1 can selectively adsorb CO2 from the mixture of CH4/CO2. Moreover, due to the high catalytic activity of [Cu4(COO)6N4O2] clusters, 1 is also an excellent recyclable catalyst that can chemically fix CO2 into cyclic carbonate under mild solvent-free conditions. Therefore, 1 may be explored as a dual-functional material for industrial adsorption and catalysis.

Herein, we report a new 3D porous Co(II)-based metal–organic framework catalyst (Me2NH2)2[Co3(L)2(H2O)2]·2DMF (MOF I), which has been successfully prepared by using Co(II) ions and rigid V-shaped 3,5-di(2,4-dicarboxylphenyl)pyridine (H4L) via the solvothermal reaction. Structural analysis reveals that I displays a porous structure with the pore size of 16.2 × 7.2 A2 based on the trinuclear [Co3(COO)4(H2O)2N2] secondary building units (SBUs). Gas sorption experiments on the guest free sample I′ reveals a high capacity and selectivity to CO2 over CH4. And further, the catalytic explorations of the I′-catalyzed system (I′: 3 mol%; proline: 40 mol%; CH3CN: 2 mL) reveal that benzyl alcohols with different structures can be efficiently transformed into benzyl alcohols without by-products under mild conditions.

The discharge of excessive metal ions and anions into water bodies leads to the serious pollution of water and environment, which in turn has a certain impact on industry, agriculture, and human life. Because of the unique advantages of luminescent metal-organic frameworks (LMOFs), they have been successfully explored as various fluorescent probes to quickly and effectively detect these pollutants. This perspective not only introduces the design strategy and classification of LMOFs, especially the construction methods of water-stable LMOFs, but also reports the latest progresses in some LMOFs between 2016 and 2020 as well as expounds the mechanisms of LMOFs for detecting anions and cations. Moreover, the luminescence properties of LMOFs are related to the selection of metal ions, the structure of organic ligands, the pore size, and the interaction of guest molecules. Finally, the further development of LMOFs is summarized and prospected in this field.

A novel two-dimensional coordination polymer with a negatively charged framework named {[(CH3)2NH2][Zn2(L)2]·DMF}n (1) was solvothermally synthesized via the assembly of Zn(II) ions with the organic ligand H3L (2-(3,5-dicarboxylphenyl)-6-carboxyl-benzimidazole). 1 was characterized by IR spectroscopy, thermogravimetry, single-crystal, and powder X-ray diffraction methods. 1 possesses a 1D rectangle channel decorated by abundant uncoordinated imidazole N atoms and carboxylate O atoms, and is a better CO2 adsorbent and promising CO2/CH4 selective material, suggesting potential application in gas separation. Moreover, 1 can also serve as a multi-responsive sensing material for detecting nitrobenzene (NB) and Cr2O72−via a luminescence quenching effect with a low detection limit, and the mechanisms of the quenching effect and sensing properties of 1 are discussed in detail.

Two new metal–organic frameworks (MOFs), formulated as [Cd3(L)2(H2O)2]·2H2O (1) and [Zn2(L)(OH)(H2O)]·2DMA (2, DMA = N,N-dimethylacetamide), were first constructed via an unsymmetrical N-heterocyclic 5-((4-carboxypyridin-2-yl)oxy)isophthalic acid (H3L) ligand. Then, a proportion of the Zn(II) ions of 2 were substituted by fine-tuning the contents of Co(II) ions to obtain two new isomers, Co1-MOF 2 and Co2-MOF 2, the successful doping of which can be proved by PXRD, IR spectra, ICP, XPS, and SEM. The luminescent experiments suggested that complex 1 should be a good detector for detecting Fe3+ and Cr2O72− ions. More remarkably, the Co-rich MOF materials have increased gas capture for CO2 and CH4 compared to that of the Co-free isomer 2, and the absorption amount of CO2 and CH4 may rise with the increasing content of Co(II) ions in the system at higher pressure and lower temperature.

A new 3D luminescent Ba-organic framework {[Ba3L2(NMP)2(H2O)2]·2NMP·H2O}n (1) was first synthesized based on Ba(II) and a triangular-shaped bridging rigid ligand, namely 1,3,5-tris(4-carboxyphenly)benzene (H3L), via solvothermal reaction (NMP = N-methyl pyrrolidone), thereby forming a stabilized network including a one-dimensional (1D) infinite rod-like helical metal chain. 1 may be explored as a recyclable heterogeneous catalyst for the efficient fixation of CO2 to form serviceable cyclic carbonate since 1D channels remain decorated with abundant open metal sites (OMSs), and the catalytic efficiency of 1 was up to 98% for 1-bromo-2,3-propylene oxide. Simultaneously, the luminescence sensing shows that 1 has excellent response and sensitivity towards pollutants such as Fe3+, Cr2O72−, CrO42−, and [Fe(CN)6]3− ions. Moreover, 1 exhibits the particularly selective sorption towards the Congo red (CR) dye. Consequently, this study may provide a facile synthetic route for the construction of multi-functional Ba-MOF materials.

Three isostructural lanthanide metal–organic frameworks (Ln-MOFs), {[Ln(L)(H2O)2]·H2O}n (M-Ln, Ln = Eu/Tb/Dy), were prepared with a flexible 3,5-(4-carboxybenzyloxy) benzoic acid (H3L) ligand and lanthanide ions by a solvothermal method. M-Ln are two-dimensional (2D) grid layer-stacking frameworks. M-Eu exhibits excellent chemical stabilities against organic solvents and shows strong luminescence. The experimental results indicated that M-Eu could be used as an ideal fluorescent probe to detect nitrobenzene (NB) in different solvents with a lower detection limit. M-Eu can also be used as a pH sensor because of its superior water stability. Furthermore, M-Eu and M-Tb show unique strong luminescence properties with high absolute quantum yields. The quantum yields can even reach up to 11.8% and 60.5%, respectively. Simultaneously, various kinds of heterometallic doped M-EuxTb1−x MOFs were acquired by tuning the ratios of Eu3+/Tb3+ ions, showing the unique color changes from red, orange-red, orange, orange-yellow, light yellow, yellow to green.

A new series of isomorphic lanthanide metal–organic frameworks (Ln-MOFs), {[Ln2(L)3·DMF·H2O]·DMF·H2O}n (denoted as 1-Ln, Ln = Eu, Gd, Tb or EuxTb1−x), were constructed using the 4′-(1H-1,2,4-triazol-1-yl)-[1,1′-biphenyl]-3,5-dicarboxylic acid (H2L) ligand and Ln3+ ions under solvothermal conditions. 1-Ln shows a binodal (3,3,8)-connected three-dimensional (3D) framework based on a π-conjugated and uncoordinated Lewis basic triazolyl ligand. Then, six two-color doped 1-EuxTb1−x and the tri-metallic doped 1-Eu0.01Gd0.6015Tb0.3885 with white light emitting MOFs were fabricated by doping diverse concentrations of Eu3+, Tb3+ and Gd3+ ions. More interestingly, 1-Eu0.01Gd0.6015Tb0.3885 has a higher quantum yield (36.49%). Meanwhile, 1-Ln shows excellent performance in fluorescence sensing (Ksv = 1.5143 × 104 M−1) and anticounterfeiting applications.

A versatile heteropoly acid (H3PMo12O40)-catalyzed coupling of diarylmethanols with epoxides was established for the synthesis of polyaryl-substituted aldehydes. Furthermore, the catalytic system was also suitable for the reaction of diarylmethanols and diols/aldehydes. The application of such an earth-abundant, readily accessible, and nontoxic catalyst provides a green approach for the construction of polyaryl-substituted aldehydes

Three new polyoxometalate-based metal-organic frameworks (POMOFs) [Cu

The largest organic–inorganic hybrid Se-4f cluster incorporated polyoxometalate has been synthesized. It exhibits excellent Lewis acid–base catalytic activity and reusability in the gram-scale dehydration condensation reaction of hydrazines and 1,3-diketones.

Several new isostructural lanthanide metal-organic frameworks (Ln-MOFs), {[Ln

The current study compared the safety, tolerability, and pharmacokinetics of the new compound pharmaceutical preparation tazarotene clindamycin cream, and 2 single pharmaceutical preparations, tazarotene cream and clindamycin phosphate gel. Twelve healthy volunteers were enrolled in this single-center, single-blind, 3-treatment, 3-period crossover, single-dose randomized study. An 800-cm2 area on volunteers' backs was evenly smeared with 1.6 g of the test preparation to form a film. Blood samples were collected at predetermined time points for pharmacokinetic analysis. Safety and tolerability were assessed via skin reaction evaluation and clinical laboratory tests. The incidences of skin reactions were 18.2% for tazarotene clindamycin cream, 25.0% for tazarotene cream, and 18.2% for clindamycin phosphate gel. There were no significant differences in safety or tolerability among the 3 groups. Erythema, desquamation, and pruritus occurred in 7 volunteers, but no burning or tingling occurred. All adverse events were mild and resolved spontaneously, and there were no severe adverse events. The respective maximum plasma concentrations of tazarotenic acid after local administration of tazarotene clindamycin cream and tazarotene cream were 11 ± 5 pg/mL and 18 ± 12 pg/mL, and the areas under the curve within 72 hours were 444 ± 341 pg · h/mL and 692 ± 462 pg · h/mL.

We compared the demographic structure and reproductive output of the critically endangered tree Pterospermum kingtungense population in different size forest fragments (5-ha and 15-ha) and continuous forests in southwestern China. Specifically, we tried to answer the following questions: (1) are habitat fragmentations affecting the population demographic structure? (2) Do the plant reproductive outputs vary in the different size forest fragments compared with continuous forests? Within each of the three habitats, three permanent demographic plot of 50 m × 100 m in size were established and surveyed. We found that the density of P. kingtungense is relatively higher in the 15-ha fragment and continuous forests than in the 5-ha forest fragment, but the difference is not significant in the three habitats. Large trees (dbh ≥ 15 cm) were significantly higher in continuous and 15-ha forest fragments than that of the 5-ha forest fragment, whereas no seedlings occurred in the 5-ha forest fragment. The flowering proportion of the P. kingtungense populations was also lower in the 5-ha fragments than that of 15-ha fragment and continuous forests. During the investigation, no flowering occurred in the 5-ha forest fragments for two consecutive years, indicating that habitat fragmentation has an effect on the reproduction of the population. Due to the self-compatible of the species, the fruit and seed settings of the two types of forest fragment were similar to that of the continuous forests. Our findings showed an alteration of basic underlying demographic properties due to forest fragmentation, which may influence the population dynamic of P. kingtungense.

Two new different metal–organic frameworks (MOFs) [Ba(L1)(H2O)2]n·nH2O (MOF 1) and [Ba(L2)(H2O)2]n·0.5nDMF·0.5nH2O (MOF 2) were yielded by the assembly of oxygen-friendly Ba(II) ions and two similar linkers, namely 2-(imidazol-1-yl)terephthalic acid (H2L1) and 2-(1H-1,2,4-triazol-1-yl) terephthalic acid (H2L2). Single-crystal X-ray diffractions (XRD) indicate that MOF 1 is a new three-dimensional (3D) stacking dense network formed by the one-dimensional (1D) rod-shaped chains and L1 linkers, whereas MOF 2 presents a 3D nanotube porous framework with cylindrical tunnels based on the 1D loop chains as the secondary building units (SBUs) by replacing the imidazole group in H2L1 with the triazole group in H2L2. As a result, MOF 2 has a higher density of active sites and Lewis acid sites in the porous surface of nanotube than MOF 1. Thereby, the CO2 capture and separation capacity of MOF 2 is great higher than that of CH4 at 298 K.

The coordination preference of different metal ions and ligands have an immense influence on the constructions of functional MOF materials. In this work, two new monometallic complexes, namely [Ag(HL)(bipy)0.5 ] (1) and {[Tb(L)1.5 (H2 O)]⋅4 H2 O}n (2) (bipy=4,4-bipyridine), have been synthesized successfully by employing a bifunctional 2-(imidazol-1-yl)terephthalic acid (H2 L) ligand. After that, two new different heterometallic-organic frameworks (HMOFs), namely {[TbAg(L)2 (H2 O)3 ]⋅H2 O}n (3) and [TbAg(L)2 (H2 O)]n (4), were obtained from complexes 1 and 2 as the precursors based on a rational stepwise construction strategy and the theory of hard and soft acids and bases (HSAB principle), respectively. The HMOFs bearing dual metallic catalytic sites (Tb and Ag) can be used as heterogeneous catalysts without losing performance for the chemical fixation of CO2 with epoxides including the sterically hindered epoxides, demonstrating some of the highest reported catalytic activity values. This work may provide a new synthetic route toward tailoring new HMOFs with excellent catalytic activity.