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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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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 Å2 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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(H2O)]⋅4 H2O}n (2) (bipy=4,4‐bipyridine), have been synthesized successfully by employing a bifunctional 2‐(imidazol‐1‐yl)terephthalic acid (H2L) ligand. After that, two new different heterometallic–organic frameworks (HMOFs), namely {[TbAg(L)2(H2O)3]⋅H2O}n (3) and [TbAg(L)2(H2O)]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. [ABSTRACT FROM AUTHOR]

In this work, a new monometallic metal–organic framework (MOF), namely {[Pb2(L)2(H2O)]·H2O}n (1), was prepared via a N,O-mixed 2-(imidazol-1-yl)terephthalic acid (H2L) ligand and Pb(II) ions. Then, a first new porous d–p heterometallic MOF (HMOF), namely {[PbZn(L)2]·DMA·H2O}n (2), was yielded via Zn(II) ions and MOF 1 as the precursor because of the different coordination affinity of oxygen and nitrogen atoms with various metal ions. MOF 1 is a condensed packing motif, whereas HMOF 2 is a porous three-dimensional (3D) framework with unsaturated Pb(II) and Zn(II) active sites, uncoordinated carboxylate oxygen atoms and two kinds of porous channels due to the introduction of Zn(II) ions into the framework of MOF 1, which thus endowed HMOF 2 with excellent sorption and selectivity for CO2 over CH4. Moreover, HMOF 2 was explored to be an efficient heterogeneous catalyst for the fixation of CO2 with various epoxides because of the existence of the abundant unsaturated bimetallic sites as the Lewis acid. It is hoped that this work may supply an effective strategy to build plenty of d–p HMOF materials with excellent gas adsorption and catalytic properties. [ABSTRACT FROM AUTHOR]

Three new 3D isostructural lanthanide MOFs, {[Ln(L)1.5(H2O)2]⋅2H2O⋅2DMF}n (Ln=Gd, Dy and Eu, H2L=4‐(2‐carboxyvinyl)benzoic acid)), were obtained by solvothermal reaction. The three complexes are topologically expressed as the trinodal (2,4,5)‐connected nets. The thermogravimetric analysis showed that the three complexes maintained favorable thermal stability at 425 °C. Further, the fluorescence detection tests showed that Eu‐MOF had excellent recognition ability to Fe3+ and small organic nitrobenzene in DMF and other different mixed solutions, with stable crystal skeleton revealed by PXRD date. In addition, the result of the magnetic testing showed that Dy‐MOF had antiferromagnetic properties at 1000 Oe. [ABSTRACT FROM AUTHOR]