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A family of 2H-chromen-2-one derivatives were identified as G protein-coupled receptor-35 (GPR35) agonists using dynamic mass redistribution assays in HT-29 cells. The compounds with 1H-tetrazol-5-yl in 3-substituted position displayed higher potency than the corresponding carboxyl analogs, and the hydroxyl group in the 7-position also played an important role in GPR35 agonistic activity. 6-Bromo-7-hydroxy-8-nitro-3-(1H-tetrazol-5-yl)-2H-chromen-2-one (50) was found to be the most potent GPR35 agonist with an EC50 of 5.8 nM. Calculating the physicochemical properties of compounds with moderate to high potency suggested that compounds 30, 50, and 51 showed good druggability. This study provides a novel series of GPR35 agonists, and compound 50 may be a powerful tool to study GPR35.

Cocatalyst-free ionic liquid (IL)-based porous polymers (Px-Vy-OHzR) functionalized with an intermolecular hydroxyl group were prepared by means of radical copolymerization of 1-butyl-3-vinylimidazolium bromide, (4-vinylphenyl)methanol (VBzOH), and divinylbenzene (DVB) under solvothermal conditions. As the ratio of 4-vinylphenylmethanol in the initial mixture increased, the content of the hydroxyl groups in the polymer increased from 3.35 to 5.35 mmol g−1 and the Brunauer–Emmett–Teller (BET) surface area of the polymer decreased sharply from 365 to 2.5 m2 g−1. In the carbonation of CO2 and epoxides, the turnover frequency (TOF) of Px-Vy-OHzR increased gradually from 25 to 67 h−1 as the OH ratio increased irrespective of the sharp decrease in BET surface area, which suggests the existence of a cooperative activation effect between OH and ILs. To obtain a high OH content while still maintaining a high BET surface area, hybrid porous materials (SBA-[VxOHy]R-n) were prepared by means of copolymerization of 1-ethyl-3-vinylimidazolium bromide and 4-vinylphenylmethanol in the mesopores of SBA-15. SBA-[VxOHy]R-n was more active than its polymer counterpart (TOF: 188 versus 71 h−1) in the cycloaddition of CO2 with propyl oxide owing to the combined effect of the high BET surface area and the high OH content. The hybridization of mesoporous materials with polymers represents an efficient strategy for the preparation of high-performance solid catalysts for chemical transformations.

Novel (R)-(+)-1,1-bi-2-naphthol ((R)-(+)-BINOL)-based conjugated microporous polymers (CMP1-4) with high Brunauer-Emmett-Teller (BET) surface area are synthesized through Sonogashira-Hagihara cross-coupling of di-/tetra-bromo-substituted (R)-(+)-BINOL derivatives and 1,3,5-triethynylbenzene. Fluorescence studies find that CMP4 can act as a sensitive and enantioselective sensor for chiral amino alcohols, such as 2-amino-1-propanol (AA1), 2-amino-3-methyl-1-butanol (AA2), and 2-amino-2-phenylethanol (AA3), which expands the application scope of conjugated microporous polymers.

Factors that govern inclusion of organic molecules within octa acid (OA), a synthetic deep cavity cavitand, have been delineated by examining the complexation behavior of a number of organic molecules with varying dimensions and functionalities with OA. The formation of two types of complexes has been noted: the one which we call cavitandplex is a partially open complex in which a part of the guest molecule remains exposed to water, and the other termed capsuleplex is formed through assembly of two OA molecules. In capsuleplex, the guest is protected from water. Generally, guest molecules that possess ionic head groups form cavitandplex, and all others form capsuleplex. Capsuleplex may contain one or two guest molecules within the capsule. Small organic molecules (10 A in length) may form both 2:1 and 2:2 capsuleplex, while longer ones (12 A) preferentially form 2:1 capsuleplex. Extensive 1H NMR experiments have been carried out to characterize host-guest complexes. In the absence of the guest, OA tends to aggregate in water. The extent of aggregation depends on the concentration of OA and the presence of salts in solution. We expect the information obtained from this study to be of great value in predicting the nature of complexes with a given guest and facilitating appropriate guest chosen by researchers.

A new class of tetrathiafulvalene (TTF)-based microstructures fabricated by coordinative self-assembly has been successfully prepared by a solution process. The morphology of the TTF coordination polymers is readily tuned by the variation of metal ions. Upon incorporation of Pb(2+) and Zn(2+) ions, one-dimensional (1D) wirelike microstructures and spherical polymer particles were achieved, respectively. These results indicate that the coordinative approach pursued in this work, in which the building blocks of 1 are linked in a coordination polymer chain by association with metal ions, is an efficient and versatile approach to produce more mechanically robust micro- and nanometer-sized coordination polymer materials. More interestingly, the neutral coordination polymers are conductive and magnetic at room temperature without external manipulation. Such conductivity is reminiscent of the behavior of the neutral conductive TTF in single crystals.

Low temperature photoisomerization of stilbene and 1,4-diphenyl-1,3-butadiene derivatives was found to vary depending on the organic glass employed in such studies. Examination of the combined results showed that the variation was more likely to arise from the rigidity of the organic glass at the temperature of irradiation rather than the composition of the organic glass; that is, the observed results are consistent with the possible softening of the glass that surrounds the excited substrate in the same manner as detected in the photolysis of ethyl iodide reported by Porter and co-workers. These observations successfully account for the apparent "disagreement" of reports from the Hawaii and the Florida State groups on the mechanism of photoisomerization in low temperature glasses.

The model complexes 1 – 3 of functionalized azadithiolate (ADT)-bridged Fe-only hydrogenases, [Fe 2 (Co) 6 (μ-ADT)C 6 H 4 C CR] [R = C 6 H 4 NO 2 -4 ( 1 ), C 6 H 5 ( 2 ), C 6 H 4 OCH 3 -4 ( 3 )] have been synthesized in high yields under mild conditions by using Sonogashira reaction. Spectroscopic study and X-ray crystal structural analysis of 1 demonstrate that the model complexes retain the butterfly structure of 2Fe2S model analogues. The intermolecular C–H⋯O, C–H⋯π hydrogen bonding and π–π interactions play important roles in molecular packing of 1 . In the presence of HOAc, complex 1 features the catalytic electrochemical proton reduction.

A series of tetrathiafulvalene acetylene derivatives, [TTF-Ctriple bondC-A] [A=C6H4N(CH3)2-4 (1), C6H4OCH3-4 (2), C6H5 (3), C6H4F-4 (4), C6H4NO2-4 (5), C5H4N-2 (6), C5H4N-3 (7), and C5H4N-4 (8)], have been designed and synthesized to provide insight into the nature of the donor-acceptor interaction via a pi-conjugated triple bond. The X-ray crystal structure of [TTF-(Ctriple bondC)-C6H4OCH3-4] (2) reveals that the phenyl ring linked by acetylene is almost coplanar to the plane of TTF with a dihedral angle of 3.6 degrees. The strong intermolecular C-H...O hydrogen bonding was found to direct the molecular helical assemblies with a screw pitch of 5.148 A when viewed along the a-axis. Spectroscopic and electrochemical behaviors of the tetrathiafulvalene acetylene derivatives demonstrate that the TTF unit interacts with the electron-accepting group through the triple bond, thus leading to the intramolecular charge transfer. The pyridine-substituted TTF compounds 6-8 show remarkable sensing and coordinating properties toward Pb2+. Comparison of the spectroscopic and electrochemical properties and the calculation at the B3LYP/6-31G* level available in Gaussian 03 reveals that varying the bridged unit of the TTF-pi-A system from a double bond to a triple bond leads to positive shifts for the first and second oxidation potentials of the TTF moieties, while the extent of intramolecular charge transfer interactions through the pi-conjugated triple bond is smaller than that through the double bond.

A simple, highly selective, neutral, fluorescent sensor for fluoride anions is reported. It is based on 2-ureido-4[1H]-pyrimidinone quadruple hydrogen-bonded AADD supramolecular assembly, and its assembling and disassembling processes are also able to respond to external stimuli reversibly.

Aryl methyl ketones and α,β-unsaturated ketones are reduced stereoselectively to secondary alcohols in the presence of Rh-functionalized hybrid core—shell nanospheres.

The polymer-inorganic hybrid core-shell nanospheres with n-(para-toluenesulfonyl)-1,2-diphenylethylenediamine in the core and the poly(methyl acrylate) (pma) polymer in the shell were prepared by using a sol-gel process. the surface properties of solid catalysts were modified by controlling pma and the cetyltrimethylammonium bromide surfactant in the shell. the water contact angle results suggest that the presence of pma and cetyltrimethylammonium bromide in the shell increases the surface hydrophobicity. in the rh-catalyzed transfer hydrogenation of aromatic ketones in aqueous hcoona, the solid catalyst with higher surface hydrophobicity demonstrates higher activity, which suggests that suitable surface properties increase the reaction rate by increasing the diffusion rates of hydrophobic substrates. furthermore, this heterogeneous catalyst can be reused conveniently without loss of ee values.

Gold nanoparticles are confined and stabilized within the channels of SBA-15 through the poly(ionic liquid) brushes that are anchored onto the pore walls of SBA-15. The supported gold catalyst exhibited remarkably high catalytic activities for selective oxidation of silanes into silanols using water as an oxidant without the use of organic solvents.

Mg-ptcda (ptcda = perylene-3,4,9,10-tetracarboxylic dianhydride) coordination polymer particles (CPPs) with special hexagonal tubes morphology were manufactured by a self-assembly and hydrothermal method. The growth process from unstable nanoribbons to metastable hexagonal rods to a core–shell structure and finally to the stable hexagonal tubes was achieved and investigated by SEM and XRD characterizations. The morphology of Mg-ptcda is mainly controlled by Ostwald ripening and self-templating mechanism. Mg-ptcda CPPs with various morphologies, such as hexagonal rings and snowflakes, and particle sizes from micro to nanoscale can be finely tuned using organic solvent as additives. The optical properties of Mg-ptcda CPPs show that incorporation of ptcda dyes in coordination polymers can efficiently reduce their aggregation and interaction in the solid state. Furthermore, porous MgO nanomaterials with various morphologies can be fabricated from Mg-ptcda CPP precursors by a simple thermal treatment process.

We have examined triplet photosensitized isomerization of sterically crowded derivatives of stilbene, diene, triene and styrene. Under selective triplet sensitization, several such compounds proceeded in the synthetically desirable manner of complete one-way trans to cis conversion or in a highly stereoselective manner. In the process, we have identified several systems suitable for solar irradiation as a “green” procedure for preparation of hindered olefinic isomers. A simple procedure for determining the relative efficiency of a solar reaction has also been introduced.

Two new TTF crown ether derivatives, TNC and TBC, have been synthesized and well characterized. The interaction between the TTF and crown ether moieties through a triple bond has been demonstrated to show a remarkable sensing ability towards Pb2+ over the other cations.