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Cysteine, an organic small molecule containing a sulfhydryl group, plays key roles in human physiology and disease. The detection of cysteine in vitro and in vivo is essential for further elucidating its many biological functions. Herein, we designed and synthesized a coumarin-based fluorescent probe for cysteine detection. This probe was successfully applied to the monitoring of cysteine in living HeLa cells, indicating that this probe can penetrate viable cell membranes and selectively detect cysteine in the presence of other analytes such as homocysteine and glutathione. The linear relationship of Cys in the range of 0-50 µM and the limit of detection (LOD) of the probe 1 was 1.3 μM, provides a potential possibility for the quantitative study of intracellular Cys.

Organogels with unique liquid crystalline properties are potential candidates for developing optical electronics.

A novel low-molecular-weight organogelator (1) based on thiacrown-cyclized tetrathiafulvalene has been synthesized through cross-coupling reaction of crown-fused 1,3-dithiole-2-one 3 and the thione 4 in the presence of triethyl phosphite. The molecular structure of 1 was fully characterized by nuclear magnetic resonance spectroscopy, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, and infrared spectroscopy. Gel-forming-ability experiments showed that the gelator could only form an opaque gel in dimethyl sulfoxide by sonication. The xerogel morphology observed by scanning electron microscopy showed an amorphous wrinkled structure. The gel exhibited varied responses to various external stimuli, including temperature, chemical oxidation, anions, and Na+ ions.

This article presents a nonlinear site amplification model for ground-motion prediction equations (GMPEs), using site period as site-effect proxy based on the measured shear-wave velocity profiles of selected KiK-net and K-NET sites in Japan. This model was derived using 1D equivalent-linear site-response analysis for a total of 516 measured soil-site shear-wave velocity profiles subjected to a total of 912 components of rock-site records. The modulus reduction and damping curves for each soil layer were assigned based on the soil-type description for a particular layer. The site period and site impedance ratio affect both the linear and nonlinear parts of this study, and were used as the site parameters in the 1D amplification model. A large impedance ratio enhances the amplification ratios when the site responds elastically and enhances the nonlinear response when the site develops a significant nonlinear response. The effects of moment magnitude and source distance on the linear part of the 1D amplification model were also incorporated in the model. To implement the 1D amplification model into GMPEs, a model adjustment is required to match the GMPE amplification ratio at weak motion and to retain the nonlinear amplification ratio at the strong motion of the 1D model. The two-step adjustment method by Zhao, Hu, et al. (2015) was adopted in this study with significant modifications. It is not possible to obtain a credible second-step adjustment parameter using the GMPEs dataset only. We proposed three methods for calculating the scale factors. Method 1 is a constant angle in a 30°–60° range for all spectral periods; method 2 was based on the GMPE dataset and 1-D model parameters; and method 3 was based on the strong-motion records used for the 1D site modeling. A simple second-step adjustment factor leads to smoothing amplification ratios and soil-site spectrum.

In this manuscript we present a nonlinear site amplification model for ground-motion prediction equations (GMPEs) in Japan, using a site period-based site class and a site impedance ratio as site parameters. We used a large number of shear-wave velocity profiles from the Kiban-Kyoshin network (KiK-net) and the Kyoshin network (K-NET) to construct the one-dimensional (1D) numerical models. The strong-motion records from rock-sites in Japan with different earthquake categories and taken from the Pacific Earthquake Engineering Research Center dataset were used in this study. We fit a set of 1D site amplification models using the spectral amplification ratios derived from 1D equivalent linear analyses. Parameters of site impedance ratios for both linear and nonlinear site response were included in the 1D model. The 1D model could be implemented into GMPEs using a new proposed adjustment method. The adjusted site amplification ratios retain the nonlinear characteristics of the 1D model for strong motions and match the linear amplification ratio in GMPE for weak motions. The nonlinearity of the present site model is reasonably similar to that of the historical models, and the present site model could satisfactorily capture the nonlinear site response in empirical data.

For the development of self-assembly donor-σ-acceptor (D-σ-A) molecules, a series of D-σ-A low-molecular mass organogelators, consisting of tetrathiafulvalene (D) and cyanobiphenyl (A) connected by...

A series of ethylenedithiotetrathiafulvalene (EDT-TTF) compounds with cyanobiphenyl moieties attached with different length alkyl chains has been designed and synthesized. The phase behavior of these derivatives was investigated by a combination of polarizing optical microscopy, differential scanning calorimetry, and X-ray diffraction. Among the derivatives, the derivatives with spacer group lengths of n = 6–12 (3b–3d) show a distinct glassy transition during the heating and cooling processes, and 3c (n = 8) and 3d (n = 12) show liquid crystal (LC) phases below the isotropic temperature. An electrochemical study shows that the longer the spacer group, the more readily the target compound is oxidized. Density functional theory calculations show that the LC molecules are typical donor–σ-bridge–acceptor molecules.

Adamantane and its derivatives have been introduced into many drugs for current clinical research and some of them are used for the treatment of neurological disease and/or used as the antiviral agents as well as the agents against type-2 diabetes. Recently, there have been many relevant research reported for developing medicinal chemistry by employing the adamantyl group. In this paper, a new adamantane-based compound (3-phenyl-adamantane-1-carboxylic acid, PACA) was synthesized and characterized by X-ray diffraction(XRD), thermogravimeric analysis(TGA), Fourier transform infrared spectroscopy(FTIR), etc., which should be a beneficial complement or extension to the existing adamantyl-based materials.

Increased bacterial resistance to antibiotics is a major threat to human health, and it is particularly important to develop novel antibiotic drugs. Here, we designed a series of Schiff base thiosemicarbazone derivatives containing an adamantane moiety, and carried out structural characterization of the compounds and in vitro antibacterial activity tests. Compound 7e was as effective as the commonly-used antibiotic ampicillin against the Gram-negative bacterium Escherichia coli, and compound 7g had a good inhibitory effect against Gram-positive Bacillus subtilis. These findings provide data for the development of better thiosemicarbazone antibacterial agents.

The synthesis and characterisation of tetrasubstituted tetrathiafulvalenes (TTFs) 1a–1c, which bear photoresponsive 4ʹ-cyanoazobenzenyl units, are described. These units were linked to the TTF core through spacers of different lengths. All synthesised compounds displayed mesogenic phases over a wide temperature range and no crystallisation, but vitrified to form glassy mesogens during cooling from the isotropic melt. Compound 1a with a short spacer (n = 6) exhibited enantiotropic nematic and smectic A mesophases. In contrast, compound 1b showed monotropic smectic A and oblique columnar phases. However, compound 1c with the longest spacer (n = 10) only possessed an oblique columnar phase. The results for this compound series showed that the molecular packing pattern depended on the spacer length and that cool-crystallisation was observed upon further heating. Furthermore, cyclic voltammetry and impedance tests confirmed that compound 1a has potential applications in organic semiconductor materials. A new series of compounds derived from heterocycle TTF was successfully designed and synthesised using simple synthetic methods. All compounds formed glassy mesogens with an above-ambient glass transition temperature during cooling from the isotropic melt. With increasing spacer length, the self-assembled structures changed from Lam to Colo. These TTF‐based LCs, in combination with good electron-donating properties and the inherent optoelectronic properties of azobenzene, might be attractive new candidates for organic optoelectronic devices.

A series of symmetric, silicon-linked organic fluorescent compounds with two electron-deficient 1,3,4-oxadiazole units were synthesized and characterized. The compounds possessed a V-shaped structure with a silicon atom, which weakened π–π stacking, promoting aggregation-induced emission. The compounds were fluorescent in both solution and solid-state thin films. The efficient fluorescent behavior of the materials was confirmed through optical and electrochemical measurements. The compounds displayed excellent thermal stability, with decomposition temperatures exceeding 400 °C. Amorphous films of the compounds possessed high morphological stability. These results indicate that the compounds may be promising emissive and electron-transporting materials.

Bioinspired strategies have drawn much attention for designing intelligent hydrogels with promising performance. Herein, we present a bioinspired adhesive hydrogel driven by adenine and thymine, which are the basic units of DNA. The adhesive hydrogel exhibited promising adhesive property for the surface of various solid materials, including muscle tissues, plastics, rubbers, glasses, metals, ceramics, carnelians, and woods. The maximum peeling strength of hydrogels was 330 N m–1 on aluminum, superior to that of PAAm hydrogels with 70 N m–1. The strong adhesive behavior remained more than 30 times repeated peeling tests. Moreover, the swelling behavior, morphological structure, mechanical strength, and peeling adhesive strength were also investigated and confirmed the formation and various characteristics of adhesive hydrogels driven by adenine and thymine. Thus, the biomimetic strategy to design promising adhesive hydrogels can provide various opportunities in tissue engineering, such as wound dressing, b...

Chronic myelogenous leukemia (CML) is a disease of the blood stem cells that features the oncoprotein Bcr-Abl. Tyrosine kinase inhibitors (TKIs) are used to treat CML patients, but these have limited efficacy due to the emergence of resistance via genetic mutation. Kamebakaurin is an ent-kaurane diterpenoid that has been isolated from Rabdosia excisa (Maxim.) H.Hara. Herein, we investigate the potential of kamebakaurin as a chemotherapy reagent for the treatment of CML. We conducted in vitro and in vivo biological experiments and found that kamebakaurin potently inhibits cell proliferation, mainly by enhancing cell apoptosis and down-regulating Bcr-Abl protein levels. In addition, kamebakaurin was found to inhibit tumor growth and has no side effects on five internal organs for in vivo experiment. These results suggest that kamebakaurin is a potential anticancer agent and is a key compound for further investigations.

Chronic myelogenous leukemia (CML) is a disease of the blood stem cells that features the oncoprotein Bcr-Abl. Tyrosine kinase inhibitors (TKIs) are used to treat CML patients, but these have limited efficacy due to the emergence of resistance via genetic mutation. Kamebakaurin is an ent-kaurane diterpenoid that has been isolated from Rabdosia excisa (Maxim.) H.Hara. Herein, we investigate the potential of kamebakaurin as a chemotherapy reagent for the treatment of CML. We conducted in vitro and in vivo biological experiments and found that kamebakaurin potently inhibits cell proliferation, mainly by enhancing cell apoptosis and down-regulating Bcr-Abl protein levels. In addition, kamebakaurin was found to inhibit tumor growth and has no side effects on five internal organs for in vivo experiment. These results suggest that kamebakaurin is a potential anticancer agent and is a key compound for further investigations.

A novel, silicon-linked, symmetric, V-shaped, coumarin derivative (1) with an electron-deficient 1,3,4-oxadiazoles unit and a phenyl moiety was synthesized and characterized. An efficient multifunctional organic light-emitting diode material was obtained through the use of optical, electrochemical, thermal, and theoretical investigations. We show that the Si atom induces a V-shaped structure that weakens π–π stacking and thus limits aggregation-induced quenching. As expected, a gradual transition from a locally excited state to an intramolecular charge-transfer state is observed with increasing solvent polarity. This new type of compound exhibits tunable light emission in solution making it a versatile emitter.

The frequency content of strong ground motions from subduction slab earthquakes differs significantly from that of ground motions produced by other categories (tectonic locations: shallow crustal, upper mantle, and subduction interface) of earthquakes in subduction zones. In the last two decades, a large number of records from subduction slab events have been obtained in Japan. We present a ground‐motion prediction equation (GMPE) for this category of earthquakes. We used a large dataset from reliably identified slab events up to the end of 2012. The GMPEs were based on a set of simple geometric attenuation functions, site classes were used as site terms, and nonlinear site amplification ratios were adopted. A bilinear magnitude‐scaling function was adopted for large earthquakes with moment magnitude M w≥7.1, with the scaling rates for large events being much smaller than for the smaller events. A magnitude‐squared term was used for events with M w

A novel magnesium-base and metal-free norphthalocyanine ( 6 and 7 ) containing peripheral thiacrown ether-linked tetrathiafulvalene moieties have been synthesized and fully characterized. Electrochemical investigations showed two quasi-reversible one-electron oxidation waves, one irreversible one-electron oxidation wave and two irreversible one-electron reduction waves, indicating that these triads are good π-electron donors. Triad 6 reacted with 2,3,5,6-tetrafluoro-7,7,8,8-tetra-cyanoquinodimethane (F 4 TCNQ) to form a charge transfer complex that exhibited absorption bands in the vicinity of 750 and 960 nm. Compound 6 showed evident intramolecular charge transfer interactions in ground states and these may be explained on the basis of the density functional theory.

A novel highly conjugated donor–acceptor dyad composed of a tetrathiafulvalene (TTF) moiety covalently attached to a magnesium norphthalocyanine (NPc) unit (1) has been synthesized and full characterized. Ultraviolet–visible spectroscopy and electron paramagnetic resonance data reveal that 1 forms an electron transfer complex with 2,3,5,6-tetrafluoro-7,7,8,8-tetra-cyanoquinodimethane (F4TCNQ). Detailed electrochemical investigations show one irreversible one-electron oxidation wave, two quasi-reversible one-electron oxidation waves, and two irreversible one-electron reduction waves, indicating that 1 is a good π-electron donor. Compound 1 shows clear intramolecular charge transfer (ICT) interactions from the tetrathiafulvalene fragments to the norphthalocyanine core. This phenomenon can be explained by density functional theory (DFT).

A series of symmetric sulfone-linked organic fluorescent compounds (1a&ndash, c) was synthesized and characterized. V-shaped 1a&ndash, c were designed as aggregate of intramolecular charge transfer (ICT) and aggregation-induced emission enhancement (AIEE) processes. The 1a&ndash, c emitted intense blue violet lights in normal solvents. A large red shift of the emission wavelength and dramatic decrease of emission efficiency occurred with increasing solvent polarity. The 1a&ndash, c will function well as electron transport and blue light-emitting materials through theoretical calculations.

A series of novel, symmetric, silicon-linked, V-shaped, organic fluorescent compounds 1a–c with an electron-deficient 1,3,4-oxadizoles unit and a diphenyl moiety were successfully synthesized. We show that the Si atom possesses a special V-shaped structure that weakens π–π stacking resulting in aggregation-induced emission. This new type of compound may show tunable light emission in solution and in a solid-state thin film. Theoretical calculations were used to analyze the frontier molecular orbitals of the two compounds. The HOMO and LUMO energy levels of the studied compounds range from −1.55 to −1.78 eV and from −5.70 to −6.15 eV, indicating that they will function well as electron transport materials.

All synthetic procedures and listing of data parameters are presented

The title compound was prepared via a cross-coupling reaction and its crystal structure has been determined. It crystallized in the triclinic space group P-1 with cell parameters: a = 8.552(2) Å, b = 11.310(2) Å, c = 16.150(3) Å, α = 109.55(3)°, β = 91.45(3)°, γ = 91.28(3)°, V = 1470.6(5) Å3, Z = 2 at 296 K. There is one molecule in the asymmetric unit. In the crystal structure, the neighboring molecules from dimers by weak intermolecular π···π interactions between the pyrrole and tetrathiafulvalene units. The dimers are further linked through C-H···π interactions to generate one-dimensional chains along the [100] direction. The arrangement of the molecules corresponds to an overlap between the HOMO and LUMO.

A serials of Cd(II) coordination polymers have been attained through hydrothermal self-assembly. During the selfassembly, the flexibility and the scale in length of the ligands play an important role in the construction of interdigitated molecular structures, which supports an alternative approach for designing such networks under the guidance of spacers. Accepted version

The complete molecule of the title compound, C18H20O4Si, is generated by crystallographic twofold symmetry, with the Si atom lying on the rotation axis. The molecule adopts a V-shape: the dihedral angle between the benzene ring and it attached methyl formate unit is 9.3 (2)°, and the dihedral angle between the benzene rings is 68.8 (1)°. In the crystal, weak C—H...O hydrogen bonds link the molecules into [101] chains.

A series of tetrakis(tetrathiafulvalene-tetrathiacrown ether)porphyrazine triads with long and flexible aliphatic side-chains at the periphery have been synthesized and characterized. Electrochemical investigations show two reversible four-electron oxidation waves, one reversible one-electron oxidation wave and two irreversible one-electron reduction waves, which indicates that these triads are good π-electron donors. Selected triad 4a reacted with 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ) to form a charge-transfer complex, which exhibits absorption bands at around 760 and 860 nm. Selected triads 4a and 5a bind silver(I) and mercury(II) ions. In the case of triad 4a, the addition of silver(I) ions led to dimerization of the triad, which fragmented to form monomeric 4:1 host–guest complexes when more than 2 equiv. of the metal ions were added. X-ray scattering at room temperature showed that triad 5c is a highly ordered oblique columnar structure in the bulk state. The crystal structures of the precursors 3b,c were also determined by X-ray diffraction analysis.

Bipedal 1,3-dithiole-2-thiones attached two cholesteryl through a ω-thioalkanoyloxy spacer of varying length were synthesized. The bipedals were easily transformed to the appropriate tetrapedal tetrathiafulvalene derivatives by self-coupling reaction in net triethyl phosphite. All the synthesized compounds exhibit mesogenic phases in a wide temperature region, no crystallization but vitrifying to form glassy mesogens during cooling from the isotropic melt. The liquid crystals with shorter spacer (n=2–6) exhibited only a smectic A phase and those with the longest spacer (n=7) exhibited only a hexagonal columnar. In these series, the molecular packing depended on the length of spacers.

Jiangsu Key Laboratory for Chemistry of Low-Dimentional Materials, Huaiyin Teachers College, Huaiyin 223300, P. R. China(Received: 30 August 2009. Accepted: 2 November 2009)A novel amidothiourea based multisensing anion chemosensor bearing a monopyrrolo[3,4- b]tetrathiafulvalene moiety ( 1) have been designed and synthesized. The receptor 1s hows a higheffective multisensing for both acetate anions and ”uoride anions over various anions in CH

Three novel tetrathiafulvalene-annulated metalloporphyrazines with electron-withdrawing pentoxycarbonyl groups at the periphery were synthesized via the cyclotetramerization of dipentyl 6,7-dicyanotetrathiafulvalen-2,3-dicarboxylate in the presence of corresponding metal salts ( Zn(OAc)2·2H2O , Cu(OAc)2·2H2O , and NiCl2 ) and in pentanol. Molecular structures were fully characterized by 1H NMR, FT-IR, UV-vis, MALDI-TOF mass spectra and elemental analysis. These newly synthesized macrocyclic dyes were sufficiently stable in air during the purification process and also in further experiments. Electron-withdrawing substituents reduced the ability of tetrathiafulvalene groups to form radical cations. Solution electrochemical data showed one reductive and three oxidative processes within a -2000 mV to +2200 mV potential window. The four couples observed were assigned to Pz -2/ Pz -3 (I), TTF +•/ TTF (II), TTF +2/ TTF +• (III) and Pz -1/ Pz -2 (IV).

Novel magnesium and metal-free porphyrazines (4 and 5) containing four peripheral tetrathiacrown ether-linked tetrathiafulvalene moieties have been synthesized and characterized. Their solution electrochemical data showed two reductive and three oxidative processes within a −1500 mV to +1500 mV potential window. UV/Vis spectroscopy and electron paramagnetic resonance (EPR) measurements reveal the formation of a charge-transfer complex between porphyrazine 4 with F4TCNQ. The single-crystal structure of the TTF-dicyanocrown ether 3 is presented.

A series of novel dimesogenic compounds containing cholesterol and 4-(trans-4-n-alkylcyclohexyl)benzoic acid moieties were synthesized. The two mesogenic units of these compounds are linked with ω-oxyalkanoyl spacers of varying lengths. The chemical structure and mesomorphic properties of this series of compounds were characterized by FT-IR, MS, 1H NMR, polarizing optical microscopy (POM) and DSC techniques. The average viscosity and helical twisting power (HTP) in host liquid crystals of selected dimesogenic compounds were also measured. It was found that most of the present novel series of compounds exhibited only cholesteric mesophase with lower phase transition temperatures, and the average viscosity and HTP of selected compounds were similar to or superior to cholesteryl nonylate.

A new series of tetrathiafulvalene-based organogelators endowed with four hydrophobic chains incorporating amide groups was synthesised and characterised. The resulting transparent organogels were obtained with organic solvents such as cyclohexane, carbon tetrachloride and chlorobenzene. Additionally, the length of the alkyl chain influenced the gelation ability of organogels. Considering the results, we concluded that compounds were ‘super gelators’. Interestingly, the gelators reacted with 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane to form charge-transfer (CT) complexes and binary organogels. 1HNMR and FT-IR revealed that cooperation of hydrogen bonding, π–π and CT interactions was the main driving force for formation of the native and CT gels. The scanning electron microscopy images of native xerogels revealed characteristic gelation morphologies of three-dimensional cross-linking networks, whereas the morphologies of CT complex xerogels showed amorphous rod-like aggregates. X-ray powder diffraction studies suggested that both gelator and CT complex maintained lamellar molecular packing mode in organogel phase.

A functional monomer, containing a 34-membered monoazacrown ether unit (VACE) as a pendant group has been synthesized by using resorcinol, tetraethylene glycol, p-tolenesulfonyl chloride and 4-vinylbenzyl chloride as starting materials. The product structure was characterized by means of FT-IR,1H-NMR, EA and MS. Free radical homopolymerized VACE or copolymerized VACE with styrene (ST) by the conventional radical initiator 2,2′-azobis (isobutyronitrile) (AIBN) in toluene solution to afford corresponding polymers. The reactivity ratio of VACE and ST, determined by Fineman-Ross method, gave values 0.6 for VACE, and 1.4 for ST, respectively.

Hypoxia inducible factor-1 (HIF-1) is a key mediator during cancer cells to adapt tumor hypoxic condition. In this study, a series of adamantane-based compounds were synthesized and evaluated as potential inhibitors of HIF-1α. Examination of their structure-activity relationship (SAR) identified the adamantane-containing indole derivative 20a as a potent inhibitor of HIF-1α in Hep3B cell lines under tumor hypoxia (IC50 = 0.02 µM). The study herein may provide valuable information for the development of novel therapeutics against cancer and tumor angiogenesis.

Two new norphthalocyanine derivatives (III) and its free base, which are composed of two TTF units as electron donor and a norphthalocyanine ring as acceptor moiety, covalently linked with two ethylenedithio spacers, are synthesized by mixed condensation of phthalonitrile (II) in excess with dithiomaleonitrile (I) using Mg(II) as a template.

In the title compound, C16H16N2O3S6, the two five-membered rings form a dihedral angle of 7.86 (9)°. Weak C—H...N hydrogen bonds link the molecules to form a chain along c; the chains are further connected by weak C—H...O hydrogen bonds to form a three-dimensional supramolecular network.

In the title molecule, C14H18OS8, one O atom, two S atoms and six C atoms form an 11-membered ring with a chair-like conformation; the planes of the two five-membered rings connected by a carbon–carbon double bond form a dihedral angle of 29.97 (11)°. In the crystal, pairs of weak intermolecular C—H...S hydrogen bonds link two molecules into inversion dimers.

In the title molecule, C11H16O2S5, the two S atoms from the macrocycle are situated on opposite sides of the mean plane of the five-membered ring, deviating from it by 1.288 (3) and 1.728 (3) Å. In the crystal, weak intermolecular C—H...S and C—H...O hydrogen bonds link the molecules into layers parallel to (100). The crystal studied was a racemic twin.

A water-soluble fluorescent sensor (L) based on 2-(2-(8-hydroxyquinolin)-yl)benzimidazole has been synthesized and characterized. Sensor L displays highly selective and sensitive recognition of Hg2+ with a fluorescence “ON–OFF” response in buffered aqueous solution (1% dimethyl sulfoxide (DMSO), Tris–HCl 10 mM, pH = 7.4). X-ray crystal structure of the L–Hg2+ complex reveals that the oxygen and nitrogen atoms of 8-hydroxyquinoline and the imine N atom of the benzimidazole unit (N1) bind Hg2+ through a 1 : 1 binding stoichiometry. The fluorescence quenching mechanism is qualitatively evaluated by quantum chemical calculations which show that the fluorescence quenching phenomenon is caused by ligand-to-metal charge transfer (LMCT) in the excited state.

In the title compound, C18H23NOS6, the dithiolopyrrole ring is almost planar [r.m.s. deviation = 0.044 (3) Å] and makes a dihedral angle of 25.11 (7)° with the dithiole ring. In the crystal, pairs of neighboring molecules are connected by weak intermolecular C—H...O interactions. These dimers are further linked into a chain along [110] by C—H...O interactions.