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Abstract: Adsorption properties of magnetic species in nano-porous crystals were studied theoretically. The crystal [Rh2bza4pyz] n , which had been reported by Mori, Takamizawa and their co-workers in detailed, was employed in this study. As adsorbed magnetic radicals, a oxygen molecule (O2; S =1) was treated. From the results by our MO calculations, weak magnetic interactions between O2 molecules in cavities existed. Two types of magnetic interactions (ferro- and antiferro-magnetic) made alignment of trimer spin structure. Our theoretical calculations analyzed not only position but also orientation of the adsorbed O2 molecules. For the position, cloud of mass densities of O2 molecules by MD simulation showed stacking styles in nano-pores statistically. Number of adsorbed gas was estimated to be 3.00 molecules/unit. For the orientation, a certain adsorbed O2 molecule was stabilized by contribution of the two next O2 molecules as well as four phenyl groups. [Copyright &y& Elsevier]

A new series of microporous materials containing infinite chains of mononuclear metal (Cu(II), Zn(II), Ni(II))-pyridine unit bridged by dicarboxylates, copper(II) terephthalate-pyridine, [CuII(OOCC6H4COO)(C5H5N)2(H2O)] · C5H5N · H2O (1), copper(II) terephthalate-4-phenylpyridine, [CuII(OOCC6H4COO)(C11H9N)2(H2O)] · (MeOH)2 (2), zinc(II) fumarate-pyridine, [ZnII(OOCC2H2COO)(C5H5N)3] · C5H5N · (H2O)0.5 (3), zinc(II) terephthalate-pyridine, [ZnII(OOCC6H4COO)(C5H5N)2(H2O)2] · (C5H5N)2 · (H2O)2 (4), nickel(II) fumarate-pyridine, [NiII(OOCC2H2COO)(C5H5N)3] · C5H5N · (H2O)2 (5), and nickel(II) terephthalate-pyridine, [NiII(OOCC6H4COO)(C5H5N)3]6 · (C5H5N)2 · (DMF)6 · (H2O)9 (6), have been prepared. A porous structure, which is formed by stacking and self-assembly of the linear metal(II) dicarboxylates, has been determined by X-ray crystallography. When released with guest solvents, these complexes, except for 5, occlude large amounts of gases such as N2 and Ar. The maximum amount of N2 gas is 0.7–10.7 mol per mole of metal(II) salt, indicating the presence of a large number of micro- and/or mesopores. The magnetic susceptibilities of 1 and 2 obey the Curie–Weiss law over the range of 70–300 K (θ=-1.4 K and θ=+5.5 K, respectively); the obtained Weiss constants (θ) indicate the existence of small antiferromagnetic interactions (1), and ferromagnetic interactions (2). The different magnetic behaviors between 1 and 2 demonstrate that hydrogen bonding between the carboxylate groups and coordinated water molecules plays an important role in determining the bridge geometries and superexchange interaction between the Cu(II) ions through the Cu–O–C–O–H–O–Cu pathways. In contrast to those of the copper(II) complexes, the magnetic susceptibilities of 5 and 6 obey the Curie law.Novel inclusion complexes between host microporous molybdenum(II) dicarboxylates (fumarate (7), terephthalate (8), trans–trans-muconate (9), and pyridine-2,5-dicarboxylate (10)) and guest organic polyethers (poly(ethylene glycol) (PEG) and poly(propylene glycol) (PPG)) of various molecular weights have been synthesized. The rate of complex formation depends on the shapes of the micropores and polyethers. The amount of included polyethers increases with their molecular weight, and reaches up to a saturated amount, with the exception that complex 10 does not form complex with bulky PPG. The amount of absorbed argon in the microporous molybdenum(II) dicarboxylates decreases with increase in the amount of include polyethers. The 13C CP/MAS NMR measurement of complex 8 with PEG has demonstrated that PEG chains are included in the capillaries. This is an effective method for synthesizing supramolecular complexes.Three dimensional microporous polymers of Rh fumarate (Rh(f)) (11), Rh terephthalate (Rh(t)) (12), and a novel porphyrin rhodium coordination polymer, [Rh2(H2TCPP)] (H2TCPP=4,4′,4″,4‴-(21H,23H-porohine-5,10,15,20-tetrayl)tetrakis benzoic acid) complexes (13) have exhibited high catalytic activities for hydrogen exchange and hydrogenation of olefins (ethylene, propene, and butene) at 200 K. The turnover frequencies of complexes 11, 12, and 13 for hydrogenation of ethylene at 194 K are much higher than those of other published Rh-containing materials. The microwave spectroscopic analyses of the deuterium isotopic distribution of formed propene-d1 during C3H6–C3D6 reaction over complexes 11 and 12 reveal that the hydrogen exchange reactions take place only inside the nanopores of complexes 11 and 12 without complete scission of C–H bond of olefin molecule. Such a novel bimolecular pathway may play an important role for development of new heterogeneous hydrogenation catalysts. [Copyright &y& Elsevier]

A novel crystalline solid, [Cu(II)2(O2CPh)4(2,5-dmpyz)]n (2,5-dmpyz = 2,5-dimethyl-pyrazine), was synthesized and characterized by single-crystal X-ray diffraction analysis. The compound demonstrates multistep phase transition induced by CO2 adsorption, which readily obeys the Clausius–Clapeyron equation in terms of the set of partial pressures of CO2 and transition temperatures. [Copyright &y& Elsevier]

A novel crystalline solid, [Cu(II)2(O2CPh)4(pyz)]n, was synthesized and characterized by single-crystal X-ray diffraction analysis; the compound demonstrates thermal phase transition that is correlated with CO2 adsorption. [Copyright &y& Elsevier]

Abstract: The first total syntheses of (−)-dysibetaine CPa and the antipode have been achieved using enantioselective solvolysis of meso-cyclic anhydride mediated by quinine derivative as an organocatalyst. The synthesis features a demonstration of an enantiodivergent organic synthesis of both enantiomers of dysibetaine CPa whereby the absolute configurations of natural product were elucidated as (3R,4R). Application of the present methodology to an enantiomerically pure novel GABA analog is also reported. [Copyright &y& Elsevier]

Abstract: Here we report total synthesis of enantiomerically pure dysibetaine CPa, isolated from Micronesian marine sponge and expected to serve as a neuroactive agent. Starting from meso-cyclopropane triester, the synthesis was achieved in 12.8% overall yield over 10 steps including organocatalytic enantioselective solvolysis of meso-succinic anhydride as a key step. This work established the absolute configurations of the natural product as (3R,4R). [Copyright &y& Elsevier]

Abstract: The crystal structure of the thermoelectric clathrate Sn24P19.3I8 was determined down to 10K showing no variations with the temperature. Even at 10K Sn24P19.3I8 crystallizes in the type-I clathrate structure, space group Pm3-n, with the cubic unit cell parameter ranging from 10.9173Å at 10K to 10.9554Å at room temperature. In its crystal structure, tin and phosphorus atoms form the framework that traps the guest iodine atoms in the polyhedral cavities of two different shapes. The temperature-dependent crystal structure data and the results of the heat capacity measurements revealed the localized vibrations of the guest atoms inside the oversized cavities with the characteristic Einstein temperatures of θ E1 =60K and θ E2 =78K, whereas the characteristic Debye temperature for Sn24P19.3I8 is 265K. The room temperature lattice thermal conductivity was calculated using the Debye model to be κ L =0.85Wm−1 K−1, which is in excellent agreement with the experimentally measured data and demonstrates that the thermal conductivity is almost entirely phononic. [Copyright &y& Elsevier]

Abstract: Objective: To investigate the effectiveness of montelukast, a leukotriene receptor antagonist, in alleviating the symptoms of dysmenorrhea. Study design: This prospective, double-blind, randomized, placebo-controlled study was comprised of 62 patients with dysmenorrhea who were randomly divided into 2 groups (montelukast and placebo). Data obtained from 50 patients were analyzed (montelukast: 24; placebo: 26). Using visual analog scale (VAS) scores and nonsteroidal anti-inflammatory drug (NSAID) usage per menstrual cycle, values before treatment were compared to average scores over two menstrual cycles with treatment. Results: Both the VAS scores and NSAID usage decreased significantly in both groups. The decreases were greater in the montelukast group compared to the placebo group, but the differences were not statistically significant. Nevertheless, in “highly effective cases,” which were defined as having a post-treatment value less than half of the pre-treatment value, the decreases were significantly greater in the montelukast group than in the placebo group (VAS: montelukast, 4 vs. placebo, 0 (P =0.029); NSAID: montelukast, 9 vs. placebo, 3 (P =0.031)). Conclusions: The present study found that montelukast may be effective in alleviating pain associated with dysmenorrhea in some women. Montelukast is safe and does not influence hormonal levels. Therefore, montelukast is a clinically reasonable management option to consider before prescribing a hormonal agent. [Copyright &y& Elsevier]

Abstract: The crystalline one-dimensional compounds, [M2(bza)4(pyz)] n (bza=benzoate; pyz=pyrazine; M=CuII (1)) and [M2(bza)4(2-mpyz)] n (2-mpyz=2-methylpyrazine; M=RhII (2), CuII (3)), demonstrate gas absorbency of NO. The amounts of adsorbed NO gas are 0.61 for 1, 0.30 for 2, and 0.23 for 3 per M2 unit at 195K (800Torr). The crystals of 1 adsorbed more NO molecules than did those of 2 and 3. The magnetic susceptibilities of the NO-inclusion crystals indicate that included NO molecules interact antiferromagnetically with neighboring guests without dimerization to N2O2. Magnetic behaviors indicated NO aggregation in the narrow 1D channels of 1–3 under unsaturated adsorption conditions. [Copyright &y& Elsevier]