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In this study, we report an efficient fabrication method for the membrane of a metal-organic framework (MOF) (Kgm-OEt) which is one kind of kagome-type MOF with a two-dimensional (2D) sheet structure having one-dimensional (1D) channels suitable for separation of H2 from other larger gases. The Kgm-OEt seed layer was created on an Al2 O3 substrate using layer-by-layer (LBL) growth, then a membrane was fabricated by secondary growth. The membrane on a 3-aminopropyltriethoxysilane (APTEs)-treated substrate obtained in this method was continuous and defect-free with the crystal orientation suitable for gas transportation, while the membrane grown on an unmodified substrate was loosely packed with unfavorable crystal orientation.

Accumulation of amyloid β peptides (Aβ) is thought to be one of the causal factors of Alzheimer's disease (AD). The aspartyl protease β-site amyloid precursor protein cleaving enzyme 1 (BACE1) is the rate-limiting protease for Aβ production, and therefore, BACE1 inhibition is a promising therapeutic approach for the treatment of AD. Starting with a dihydro-1,3-thiazine-based lead, Compound J, we discovered atabecestat 1 (JNJ-54861911) as a centrally efficacious BACE1 inhibitor that was advanced into the EARLY Phase 2b/3 clinical trial for the treatment of preclinical AD patients. Compound 1 demonstrated robust and dose-dependent Aβ reduction and showed sufficient safety margins in preclinical models. The potential of reactive metabolite formation was evaluated in a covalent binding study to assess its irreversible binding to human hepatocytes. Unfortunately, the EARLY trial was discontinued due to significant elevation of liver enzymes, and subsequent analysis of the clinical outcomes showed dose-related cognitive worsening.

The ortho-isomer of molecular hydrogen (o-H2) was converted to the para-isomer (p-H2) within 600 s by using Prussian blue analogs, {MII3[CrIII(CN)6]2} (MCr; M = Mn and Ni), as nuclear-spin conversi...

Here, we report the adsorptive removal of trace amounts of dimethyl sulfide (DMS) using metal–organic frameworks (MOFs). Cu2+-based MOFs with open metal sites (OMSs), [Cu3(btc)2] (HKUST-1), where btc = 1,3,5-benzenetricarboxylate, and without OMSs, [Cu2(bdc)2(dabco)] (Cu-JAST-1), where bdc = 1,4-benzenedicarboxylate and dabco = 1,4-diazabicyclo[2.2.2]octane, were investigated for the removal of DMS to compare their performance with that of Ag–Y zeolite, which is currently widely used in industry. HKUST-1 exhibited a considerably higher adsorption capacity for DMS than the other adsorbents, which was confirmed by breakthrough measurements. The adsorption state of DMS with HKUST-1 was directly revealed by single-crystal X-ray diffraction (SXRD) analysis and in situ Raman spectroscopy. In addition, it was shown that DMS can be removed by HKUST-1 even under humid conditions.

A layered metal-organic framework (MOF) comprising extra-large nanographene sheets, HBCMOF, was successfully synthesized using a dicarboxylic acid derivative of hexa-peri-hexabenzocoronene (HBCLH2), and its structure was characterized by single-crystal X-ray diffraction analysis. The crystal structure shows that 2D layers composed of a dinuclear Zn2+ complex unit and HBCL are located on top of each other through multiple weak interlayer bonds, affording HBCMOF, having three dimensionally connected nanopores with large nanographene surfaces. The HBC-based nanographene sheets are anchored to the MOF framework via two zinc carboxylate linkages and therefore have an axial rotational freedom. The sorption isotherms of gaseous molecules such as carbon dioxide and hydrocarbons (acetylene, propane, propylene, benzene, and cyclohexane) on HBCMOF all displayed a hysteretic profile with reversible structural changes, as observed by in situ powder X-ray diffraction studies.

In this study, we report a facile ligand-assisted in situ hydrothermal approach for preparation of compact [Al(OH)(1,4-NDC)] (1,4-NDC=1,4-naphthalenedicarboxylate) MOF membranes on porous γ-Al2 O3 substrates, which also served as the Al3+ source of MOF membranes. Simultaneously, it was observed that the heating mode exerted significant influence on the final microstructure and separation performance of [Al(OH)(1,4-NDC)] membranes. Compared with the conventional hydrothermal method, the employment of microwave heating led to the formation of [Al(OH)(1,4-NDC)] membranes composed of closely packed nanorods with superior H2 /CH4 selectivity.

Triplet carbenes (TCs) are of great interest due to their magnetic properties and reactivity, which descend from TCs' unique electronic state. However, the reactivity and stability of TCs are usually a trade-off, and it is difficult to achieve both at the same time. In this work, we were able to enhance the thermal stability of a TC species while maintaining its reactivity by confining them in the nanospace of a metal-organic framework (MOF). We synthesized a new MOF using a TC precursor; subsequently, TCs were generated by photostimulation. The TCs generated in the MOF nanospace were detectable up to 170 K, whereas their non-MOF-confined counterparts (bare ligand) could not be detected above 100 K. In addition, the reactivity of TC generated in MOF with O2 was drastically improved compared to that of bare ligand. Our approach is generally applicable to the stabilization of highly reactive species, whose reactivity needs to be preserved.

Molecular motions taking place in the nanospace of metal–organic frameworks (MOFs) are an interesting research subject, although not yet fully investigated. In this work, we utilized in situ Raman spectroscopy in the ultralow-frequency region to investigate the libration motion (including the rotational motion of phenylene rings) of MOFs, in particular [Cu2(bdc)2(dabco)] (Cu-JAST-1), where bdc = 1,4-benzenedicarboxylate and dabco = 1,4-diazabicyclo[2.2.2]octane. The libration mode of Cu-JAST-1 was found to be significantly suppressed by the adsorption of various guest molecules, such as CO2, Ar, and N2. In addition, an appreciable correlation between the libration mode and adsorption equilibrium time was identified, which provides useful novel tools in the design of MOFs acting as molecular adsorption and separation materials.

We aimed to investigate whether coffee, green tea, and caffeine intake are associated with liver cancer risk, using data of a prospective cohort study. This study included 30,824 participants (14,240 men and 16,584 women) aged 35 years or older in the Takayama study, which was launched on September 1, 1992. The consumption frequencies of coffee and green tea were assessed using a self-administered questionnaire. Caffeine intake was estimated from the consumption frequencies of caffeine-containing beverages and foods and their caffeine content per serving. The incidence of liver cancer was confirmed using regional population-based cancer registries. During the follow-up period of 16 years, a total of 172 participants developed liver cancer. The adjusted hazard ratios and 95% confidence intervals (CIs) in relation to coffee consumption were 0.65 (95% CI: 0.46-0.93) for less than once per day, 0.63 (95% CI: 0.39-1.02) for once per day, and 0.40 (95% CI: 0.20-0.79) for twice per day or more, compared with nondrinkers. No associations with green tea, black tea and caffeine intake were observed. The present study confirmed that coffee consumption significantly reduces liver cancer risk and raises the possibility that caffeine intake might not account for the association.

Background: There is growing evidence suggesting that soy isoflavones play a protective role in the development of cancer. However, few epidemiological studies have investigated the association between soy isoflavone intake and bladder cancer. Methods: We evaluated the associations of soy and isoflavone intakes with bladder cancer incidence in a population-based prospective study in Japan. Subjects were 14,233 men and 16,584 women age 35 years or older in September 1992. Soy and isoflavone intakes were assessed via a validated food-frequency questionnaire, while controlling for total energy intake. Cancer incidence was mainly confirmed through regional population-based cancer registries. Bladder cancer was defined as code C67 according to the International Classification of Diseases and Health Related Problems, 10th Revision. Results: During mean follow-up of 13.6 years, 120 men and 41 women had developed bladder cancer. After adjustments for multiple confounders, compared with the lowest quartile of soy food intake, the estimated hazard ratios for the second, third, and highest quartiles of soy food intake were 0.74, 0.52, and 0.55, respectively, in men (P-trend: 0.023). The corresponding values were 0.60, 0.75, and 0.64, respectively, in women (P-trend: 0.43). Similar inverse associations were observed between isoflavone intake and bladder cancer risk. Conclusions: A significant decreased risk of bladder cancer was observed among men who had higher intakes of total soy and isoflavones. Impact: Our finding on the potential benefit of consuming soy foods against bladder cancer is promising and warrants further studies. Cancer Epidemiol Biomarkers Prev; 27(11); 1371–5. ©2018 AACR.

We report herein convenient access to tetranuclear clusters of [Ln4(RPO3)2(RPO3H)(tBuCO2)7(tBuCO2H)3(H2O)3]·solvent Ln4 (Ln = Gd, Dy), from dinuclear lanthanide precursors [Ln2(O2CtBu)6(HO2CtBu)6] and a bulky phosphonate ligand (9-methyl-9H-fluoren-9-yl)phosphonic acid (RPO3H2). In the structures of Ln4, four Ln(III) ions are arranged at the vertices of an irregular quadrilateral that are wrapped by bulky hydrophobic fluorenyl groups. Magnetic studies show that Gd4 exhibits high magnetocaloric effect (MCE) with entropy change of 23.10 J kg−1 K−1 at 2.5 K for ΔH = 7 T, while Dy4 shows slow magnetic relaxation that is the character of a single-molecule magnet (SMM).

The factors influenced on degradation of direct hydrazine hydrate fuel cells (DHFCs) under operation conditions are analyzed by in situ soft X-ray radiography. A durability of DHFCs is significantly improved by multi-step reaction DHFCs (MSR-DHFCs) approach designed to decrease the crossover of liquid fuel. An open circuit voltage (OCV) as well as cell voltage at 5 mA cm−2 of MSR-DHFC construct with commercial anion exchange membrane (AEM) maintained for over of 3500 h at 60 °C. Furthermore, the commercial proton exchange membrane (PEM) is integrated into AEM of MSR-DHFCs resulting in stable power output of MSR-DHFCs for over than 2800 h at 80 °C.

In this study, it was demonstrated that the introduction of Co–Al/Mg–Al hydrotalcite-like compound buffer layers on porous α-Al2O3 substrates enabled effective manipulation of the microstructure of ZIF-7 films so that metal ions located in the inorganic buffer layers were not necessarily identical with those residing in the MOF crystals. Moreover, zinc sources were found to exert a significant influence on the final microstructure of the prepared ZIF-7 films. In addition to ZIF-7, well-intergrown ZIF-8 and HKUST-1 films could also be in situ grown on diverse HTlc buffer layer-modified α-Al2O3 substrates, which convincingly demonstrated the generality of this strategy for the facile preparation of qualified MOF films/membranes.

[Zn2(FDC)2(bpy)] (LMOF-202) and [Zn2(OFDC)2(bpy)] (LMOF-201) (FDC: fluorene-2,7-dicarboxylate, OFDC: 9-fluorenone-2,7-dicarboxylate, bpy: 4,4′-bipyridine) have interpenetrated isostructures. However, their gas sorption behaviors indicate that LMOF-202 is rigid, whereas LMOF-201 is flexible. We found that the structural flexibility of LMOF-201 was due to the addition of only one oxygen atom into the ligand.

Reaction in well-designed solids allows yielding products with high selectivity and unique compounds that cannot be obtained in solution. However, the precise tuning of the arrangement of reactants in solids for the versatile application of solid-phase reactions remains a challenging subject. Here, a [2 + 2] photocyclization reaction at different positions of the carbon-carbon bonds is described in which the spatial arrangement of 4-styrylpyridines (4-spy) is changed by guest molecules in a flexible metal-organic framework. The 4-spy molecules undergo photodimerization between two carbon-carbon double bonds in the guest-free framework, whereas a reaction between olefinic and aromatic carbon-carbon bonds or the absence of reaction takes place in the solvent-incorporated form. This reactivity, which can be termed as "dynamic topochemistry" contributes to enforce the applicability of solid-phase reactions in synthetic chemistry.

Herein, we developed isostructural metal-organic frameworks (MOFs) [Cu1-xPdx(SiF6)(bpy)2] (bpy: 4,4'-bipyridine) (SIFSIX-1-CuPd-3, -5 and -10) containing open metal sites using a partial metal-replacement approach. Starting from the SIFSIX-1-Cu-type MOF, some of the Cu2+ ions having octahedral geometry were successfully replaced with Pd2+ ions having square planar geometry in different ratios, while the framework structure was maintained. The results showed that gas adsorption properties of SIFSIX-1-Cu-type MOFs can be tuned via partial metal replacement.

The layered P2-Nax MO2 (M: transition metal) system has been widely recognized as electronic or mixed conductor. Here, we demonstrate that Co vacancies in P2-Nax CoO2 created by hydrogen reductive elimination lead to an ionic conductivity of 0.045 S cm(-1) at 25 °C. Using in situ synchrotron X-ray powder diffraction and Raman spectroscopy, the composition of the superionic conduction phase is evaluated to be Na0.61 (H3 O)0.18 Co0.93 O2 . Electromotive force measurements as well as molecular dynamics simulations indicate that the ion conducting species is proton rather than hydroxide ion. The fact that the Co-stoichiometric compound Nax (H3 O)y CoO2 does not exhibit any significant ionic conductivity proves that Co vacancies are essential for the occurrence of superionic conductivity.

The adsorptive separation of C2H2 and CO2 via porous materials is nontrivial due to the close similarities of their boiling points and kinetic diameters. In this work, we describe a new flexible porous coordination polymer (PCP) [Mn(bdc)(dpe)] (H2bdc = 1,4-benzenedicarboxylic acid, dpe = 1,2-di(4-pyridyl)ethylene) having zero-dimensional pores, which shows an adsorbate discriminatory gate effect. The compound shows gate opening type abrupt adsorption for C2H2 but not for CO2, leading to an appreciable selective adsorption of CO2 over C2H2 at near ambient temperature (273 K). The origin of this unique selectivity, as unveiled by in situ adsorption-X-ray diffraction experiments and density functional theory calculations, is due to vastly different orientations between the phenylene ring of bdc and each gas in the nanopores. The structural change by photochemical transformation of this PCP via [2 + 2] photodimerization leads to the removal of inverse CO2/C2H2 selectivity, verifying the mechanism of the guest discriminatory gate effect.

Nanoporous materials can adsorb small molecules into their nanospaces. However, the trapping of light gas molecules dissolved in solvents suffers from low concentration and poor adsorption affinity. Here, the reversible trapping and releasing of dissolved oxygen are shown through integrating photosensitization and chemical capturing abilities into a metal-organic framework (MOF), MOMF-1. 9,10-Di(4-pyridyl)anthracene (dpa) ligands in MOMF-1 generates singlet oxygen from triplet oxygen under photoirradiation without additional photosensitizers, and successively reacts with it to produce anthracene endoperoxide, forming MOMF-2, which is proved crystallographically. The reverse reaction also proceeds quantitatively by heating MOMF-2. Moreover, MOMF-1 exhibits excellent water resistance, and completely removes oxygen of ppm order concentrations in water. The new material shown in this report allows controlling of the amount of dissolved oxygen, which can be applicable in various fields relating to numerous oxidation phenomena.

Robust assembly of aromatic molecules Organic materials can exhibit high porosity, but the structures often collapse or decompose at high temperatures. Yamagishi et al. synthesized an aromatic molecule that bears a symmetrical outer shell of three dipyridylphenyl wedges and crystallized it from highly dielectric solvents. Porous crystals formed with complex pore-wall structures that resulted from labile C–H⋯N bonds and van der Waals forces. Despite the weakness of these interactions, the porous structure was stable up to 202°C and could be recovered after collapse by exposure to solvent vapor. Science , this issue p. 1242

ObjectiveTo identify a candidate biomarker reflecting biological changes during the preclinical progression of spinal and bulbar muscular atrophy (SBMA).MethodsWe analyzed longitudinal changes in biochemical parameters obtained during health examinations before and after the diagnosis of SBMA. We estimated trajectories of clinical markers across years from the onset of weakness using linear mixed models and compared these trajectories with those estimated for male healthy controls and patients with amyotrophic lateral sclerosis (ALS) and Parkinson disease (PD). Moreover, we examined the relationship between serum creatinine level and the onset of symptoms using Kaplan-Meier curves.ResultsBetween October 2014 and October 2017, we enrolled 40 patients with genetically confirmed SBMA, 48 healthy controls, 25 patients with ALS, and 20 patients with PD. In patients with SBMA, we evaluated the patients' data for a period of 17.3 ± 7.5 years, including 11.4 ± 7.1 years of preclinical phase. Decreases in serum creatinine occurred >10 years before the onset. The mean serum creatinine concentration was 0.56 mg/dL at the onset of weakness in patients with SBMA compared to 0.88 ± 0.10 mg/dL on final evaluation in healthy controls. Serum levels of alanine transaminase and aspartate transaminase showed tendencies to increase in preclinical SBMA. These preclinical changes of biomarkers were not observed in either ALS or PD.ConclusionsOur findings suggest that serum creatinine begins to decrease before the onset of clinical symptoms and is a biomarker for disease progression and the efficacy of therapeutics in preclinical SBMA.

The design of porous materials that undergo selective adsorption of a specific molecule is a critical issue in research on porous coordination polymers or metal-organic frameworks. For the purpose of the selective capture of molecules possessing an electron-acceptor character such as nitric oxide (NO), one-dimensional chain compounds possessing a high donor character have been synthesized using 4-chloroanisate-bridged paddlewheel-type dimetal(II, II) complexes with M = Ru and Rh and phenazine (phz) as the chain linker: [M2(4-Cl-2-OMePhCO2)4(phz)]·n(CH2Cl2) (M = Ru, 1; Rh, 2). These compounds are isostructural and are composed of chains with a [-{M2}-phz-] repeating unit and CH2Cl2 occupying the void space between the chains. Compounds 1 and 2 change to a new phase (1-dry and 2-dry) upon evacuating the crystallization solvent (CH2Cl2) and almost lose their pores in the drying process: no void space in 1-dry and 31.8 Å(3), corresponding to 2.9% of the cell volume, in 2-dry. Nevertheless, the compounds show a unique gas accommodation ability. Accompanied by a structural transformation (i.e., the first gate-opening) at low pressures of10 kPa, both compounds show a typical physisorption isotherm for O2 (90 K) and CO2 (195 K), with the adsorption amount of ca. 2-4 gas molecules per [M2] unit. In addition, the adsorption isotherm for NO (121 K) involves the first gate-opening followed by a second gate-opening anomaly at NO pressures of ≈52 kPa for 1-dry and ≈21 kPa for 2-dry. At the first gate-opening, the absorbed amount of NO is ca. 4 molecules per [M2] unit, and then it reaches 8.4 and 6.3 for 1-dry and 2-dry, respectively, at 95 kPa. Only the isotherm for NO exhibits hysteresis in the desorption process, and some of the NO molecules are trapped in pores even after evacuating at 121 K, although it recovers to the original dried sample on heating to room temperature. The adsorbed NO molecules accrue a significant electron donation from the host framework even in the [Rh2] derivative, indicating that such simple porous compounds with electron-donor characteristics are useful for the selective adsorption of NO.

Two 2D Hofmann-type spin-crossover coordination polymers, [Fe(stpy)2Pt(CN)4]·0.5MeOH (stpy = 4-styrylpyridine; 1) and [Fe(pep)2Pt(CN)4] {pep = 4-(2-phenylethyl)pyridine; 2}, have been prepared by using long co-ligands with different flexibilities. These compounds form 3D interdigitate structures based on 2D layers extended by Pt–CN–Fe linkages with different interlayer structures depending on the nature of the axial co-ligand. The stpy co-ligand forms one-directional π–π networks between the layers, whereas pep forms two-directional π–π networks as a result of its perpendicularly twisted structure. Coordination polymer 1 exhibits a half-spin transition with Tc = 106 K and Tc = 110 K. In contrast, coordination polymer 2 shows a sharp, two-step spin transition in the temperature range 184–236 K. The difference in spin-transition behavior is discussed in terms of the interlayer packing structure.

International audience; The effect of mineral additions based on calcium aluminates on the hydration mechanism of ordinary Portland cement (OPC) was investigated using isothermal calorimetry, thermal analysis, X-ray diffraction, scanning electron microscopy, solid state nuclear magnetic resonance and pore solution analysis. Results show that the addition of a calcium sulfoaluminate cement (CSA) to the OPC does not affect the hydration mechanism of alite but controls the aluminate dissolution. In the second blend investigated, a rapid setting cement, the amorphous calcium aluminate reacts very fast to ettringite. The release of aluminum ions strongly retards the hydration of alite but the C-S-H has a similar composition as in OPC with no additional Al to Si substitution. As in CSA-OPC, the aluminate hydration is controlled by the availability of sulfates. The coupling of thermodynamic modeling with the kinetic equations predicts the amount of hydrates and pore solution compositions as a function of time and validates the model in these systems.

Three porous coordination polymers {Fe(dpa)[Pt(CN)4]·G·nH2O} (1-G; dpa = 1,2-di(4-pyridyl)ethane, G = dpa, bibenzyl (bbz) and stilbene (stb)) have been prepared by using a long and flexible ligand dpa. These compounds formed analogous 3-D elongated Hofmann-type frameworks based on 2-D planar layers extended by Pt–CN–Fe linkages with dpa as flexible pillar ligands. 1-dpa showed a characteristic three-step spin transition (ST) in the temperature range 180–240 K. The ST behavior was reversibly modulated by dehydration and hydration processes in keeping with the three steps. 1-bbz and 1-stb exhibited a gradual three-step ST over the range 80–200 K and an abrupt ST with Tc = 163 K. The guest-dependent cooperativity of the ST behavior is discussed by considering the flexibility of the framework and guest molecules.

Four MIL-101-type porous coordination polymers were synthesized containing different substituents (–H, –NO2, –NH2, –SO3H) in the ligand and their water sorption properties were investigated. All of the compounds adsorbed huge amounts of water (ca. 0.8–1.2 g g−1) and the adsorbed water can be released at relatively low temperatures (ca. 353 K). In addition, the trapping pressure of water adsorption was found to be controlled by changing the substituents, varying the hydrophobicity of the functional groups.

Stress analysis of RC structures that have been retrofitted by an externally bonded layer of Polymer Cement Mortar (PCM) based materials requires the development of a constitutive model of the PCM-concrete interface under static and fatigue loading. In this paper, the bending fatigue and shear fatigue tests were conducted to determine the interface fatigue degradation properties by using the J-integral method based on the energy equivalence. Substrate concretes with four different compressive strengths and interface roughness were applied to understand the effects of substrate concrete and interface roughness on the fatigue degradation properties. It was found that the failure characteristics of the PCM-concrete interface is similar to those of cementitious material and the failure modes of PCM-concrete interface has an important effect on the interface tensile and shear degradation relation and S-N relation under fatigue loading. The degradation relation is similar in the case that the failure mode is identical, regardless of the type of substrate concrete. The fatigue resistance of the PCM-concrete interface is inferior to that in the concrete cohesion layer.

The ability to design and control properties of nano-sized space in porous coordination polymers (PCPs) would provide us with an ideal stage for fascinating physical and chemical phenomena. We found an interconversion of nuclear-spin isomers for hydrogen molecule H 2 adsorbed in a Hofmann-type PCP, {Fe(pz)[Pd(CN) 4 ]} (pz=pyrazine), by the temperature dependence of Raman spectra. The ortho (o)–para (p) conversion process of H 2 is forbidden for an isolated molecule. The charge density study using synchrotron radiation X-ray diffraction reveals the electric field generated in coordination nano-space. The present results corroborate similar findings observed on different systems and confirm that o–p conversion can occur on non-magnetic solids and that electric field can induce the catalytic hydrogen o–p conversion.

Circular dichroism spectroscopy revealed that the thermal stability of chicken egg white lysozyme in an aqueous buffer solution is significantly lowered by the addition of 6-O-α- d -glucosyl-β-cyclodextrin (G1-β-CD), whereas it is raised by the addition of methyl α- d -glucopyranoside. The α- and γ-cyclodextrin also lowered the thermal stability, although the effects were less prominent than that of G1-β-CD. Fluorescence spectroscopy suggested that cyclodextrins include the side chains of tryptophan residues within their internal cavities to lower the thermal stability of lysozyme. The fluorescence intensity of a sample, re-cooled to 25 °C after thermal denaturation at 75 °C in the presence of G1-β-CD, was stronger than that observed for native lysozyme. The fact that the fluorescence intensity of the re-cooling sample was stronger than that of the native one indicates that G1-β-CD persists in binding to the side chains of tryptophan residues of the re-cooled lysozyme.

The total synthesis of luotonin A was achieved in excellent yield by using a Pd-assisted biaryl coupling reaction of N-(bromoquinolinyl)methylquinazolinone with Cy3P and KOAc. The successive treatment of luotonin A with NBS and aq. AgNO3 gave luotonin B in good yield. Although the Pd-assisted coupling reaction of N-(2-bromoindolyl)ethylquinazolinone with Cy3P and KOAc yielded rutaecarpine in poor yield, N-acetate under the same reaction conditions yielded the desired rutaecarpine directly in excellent yield.

The concise synthesis of Amaryllidaceae alkaloids, such as anhydrolycorinone, anhydrolycorin-7-one, assoanine, and oxoassoanine, which have a pyrrolophenanthridine skeleton, was achieved in moderate yield using the Pd-mediated biaryl coupling reaction of 1-(2-halobenzyl)-2,3-dihydroindole, which applied the regioselective C–H activation method with intramolecular coordination of the benzylamino group to Pd.

The novel synthesis of a new skeletal compound, benzonaphthazepine, from N-bromobenzylnaphthylamine using a Pd reagent is described. In the biaryl coupling reaction of N-bromobenzylnaphthylamine using a Pd reagent, the intramolecular coordination of the benzylamino group to Pd causes regioselective C-H activation at the peri position relative to the amine group on the naphthalene ring, producing benzonaphthazepine in good to excellent yield The bulkiness of the substituent at C 7 on the naphthalene ring affects the regioselectivity of the biaryl coupling reaction.

In a biaryl coupling reaction of N-bromobenzylnaphthylamine using Pd reagent, the intramolecular coordination of the benzylamino group to Pd causes the regioselective C-H activation at the peri-position to the amine groupon the naphthalene ring to produce a new skeletal compound, naphthobenzazepine, in good to excellent yield.

Soft, Selective CO Sorption Many industrial processes produce CO, which could be used as a chemical feedstock, but separation of CO from other gases, especially N 2 , is too difficult to be economically viable. Sato et al. (p. 167 , published online 12 December 2013) now report that a porous coordination polymer containing Cu 2+ ions can selectivity bind CO through serial structural changes reminiscent of allosteric effects in proteins. The separation of CO-N 2 mixtures can be achieved with a low input energy for CO desorption.

A pressurized flow and countermigration, due to electrophoretic mobility of a solute, are used for sample concentration. An apparatus composed of two rooms with electrodes, connecting tubes, and a pump for aspirating the sample solution is proposed. The sample solution is aspirated into small tubes (1.5-mm i.d. and 15 mm long), over which a voltage is applied (300-800 V/cm). A solute of high electrophoretic mobility is found to be drawn back from the small tube. Naphthalene-sulfonic acids, herring DNA, and magnesium ions are concentrated 10-47 times under pressurized flow (0.1-0.4 mL/min). We call this method «countercurrent electroconcentration»

Total synthesis of several benzo[c]phenanthridine alkaloids was accomplished via an aryl-aryl coupling reaction using a novel Pd reagent prepared from Pd(OAc) 2 , DPPP, and Bu 3 P. This is a versatile method for the coupling reactions of not only aryl triflates and arenes hut also aryl halides and arenes.

Free polyamines in rat tissues were determined by high performance capillary electrophoresis using fluorescence detection. After precipitation of proteins with perchloric acid, the sample solution was derivatized with fluorescamine using a microscale procedure. Ethylenediamine was added to the medium to avoid adsorption of polyamines onto the capillary wall. An internal standard of 6-amino-n-caproic acid a was used. To improve detector sensitivity, the fluorescence signal was collected with a cylindrical lens. The minimum detectable amount and concentration of the sample for the present method were around 200 fmol and 10 nmol mL−1, respectively.

Total synthesis of several benzo[c]phenanthridine alkaloids was accomplished via an aryl-aryl coupling reaction using a novel Pd reagent prepared from Pd(OAc) 2 , DPPP, and Bu 3 P. This is a versatile method for the coupling reactions of not only aryl triflates and arenes hut also aryl halides and arenes.

A palladium reagent prepared from Pd (OAc) 2 (0.2 eq) and n-Bu 3 P (0.6 eq) catalyzed an aryl-aryl coupling reaction. This procedure is effective for coupling reactions of aryl triflate possessing no oxygen groups with arene, and of aryl iodide with arene.

Nontypable Haemophilus influenzae (NTHI) is one of the major pathogens of human respiratory infections and has the ability to attach to pharyngeal epithelial cells. We characterized the epithelial cell receptor to which NTHI bind. Neuraminidase pretreatment of pharyngeal epithelial cells resulted in a significant decrease in NTHI attachment, suggesting sialic acid as an important component of the receptor. The attachment was not decreased in NTHI pretreated with 1,000 microg/ml of fucose, N-acetyl-neuraminic acid, N-acetyl-glucosamine, N-acetyl-galactosamine, acetyl-salicylic acid and colominic acid. Only treatment with gangliosides D1a, D1b and D2 at a concentration of 12.5 microg/ml significantly decreased the attachment. On the other hand, treatment with gangliosides M1, M2, M3, D3, T1b and asialoganglioside M1 did not decrease the attachment of NTHI. Only ganglioside D2 inhibited the attachment significantly at a concentration of 12.5 ng/ml. Other isolates of NTHI showed a decrease in attachment after treatment with ganglioside D2. Treatment of cells with anti-human GD2 monoclonal antibody also decreased the attachment of NTHI in a dose-dependent manner. This study indicates that sialic acid glycoconjugate, GD2, is one of the receptors of NTHI on human pharyngeal epithelial cells.

In a model system of an O2–O2 dimer confined in the nanopores of Cu-1,4-cyclohexanedicarboxylic acid, the molecular orientation associated with the spin state was observed by precise synchrotron radiation structure analysis. The obtained charge density level structures revealed that the molecular orientation varied with increasing temperature, coupling with the spin states of the O2–O2 dimer. The magnetic properties previously reported were consistently explained by the \(S = 1\) dimer model taking into account the molecular arrangements. The obtained gap parameters are different from those of the O2–O2 dimer confined in the nanopores of Cu-2,3-pyrazinedicarboxylate-pyrazine, which is explained by the pore deformation due to the adsorption, depending on the pore size and/or flexibility of the coordination polymer.

To implement specific guest responsivity, a hydrophobic cholesterol-based co-ligand, cholest-5-en-3-yl-4-isonicotinate (Cholpy), was incorporated into a two-dimensional Hofmann-type Co(II)Ni(II) coordination polymer. The chemically programmed structure successfully demonstrated the unique guest response with remarkable chromatic changes.

High-field magnetization measurements have been performed at various temperatures on the molecular oxygen adsorbed in a microporous coordination polymer CPL-1. Molecular oxygen with S = 1 forms O2-O2 dimer in the nanochannels of CPL-1. The magnetic properties can be explained by not the S = 1 Heisenberg antiferromagnetic dimer model but the O2-O2 dimer model taking into account the spin-dependent intermolecular potential. This feature is attributed to the fact that the magnetic interaction between O2 is comparable to the van der Waals force.