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The recombinant D2 domain of fibroblast growth factor receptor (FGFR) 2 is purified to homogeneity using nickel affinity and heparin-Sepharose chromatography. The result shows that the D2 domain is an all-beta-sheet protein and is capable of binding to both herapin and the ligand, hFGF-1.

Fluorous metal-organic framework with the formula [{[Ag.sub.2][[Ag.sub.4][Tz.sub.6]}.sub.n] (FMOF-1) has represented a new class of porous materials with superior volumetric gas uptake. The fluorous coordination polymers of this type can be used in gas storage and separation, catalysis, sensors, switches, actuators and n-type field-effect transistors.

A cyclic gold(I) trizolate trimer, [Au(3,5-i-Pr2Tz)]3 represents a new class of phosphorescent complexes with a remarkable photophysical behavior, several aspect of which are summarized. This trimer exhibits fully overlapping aurophilically bonded dimer-of-trimer units that lead to multiple phosphorescence bands in both the solid state and solution.

A rhodium-catalyzed hydroacylation of para-quinone methides (p-QMs) with salicylaldehydes has been disclosed. This method allows for the construction of α,α-diaryl-2-hydroxy acetophenones through tandem C-H activation/C-C bond formation/aromatization process. Moreover, this unprecedented hydroacylation of trisubstituted alkenes exhibits good yields with broad functional group tolerance as well as gram-scale capacity. [ABSTRACT FROM AUTHOR]

The cooperative palladium/l-proline-catalyzed direct α-allylic alkylation of ketones with alkynes is achieved. This reaction exhibits high atom economy since a leaving group is not liberated and a stoichiometric amount of extra oxidant is not needed. A broad range of functional groups are tolerated, and the reaction scope could be further expanded to aldehydes. [ABSTRACT FROM AUTHOR]

A novel [3 + 2] cycloaddition reaction between in situ formed azaoxyallyl cations and aldehydes has been developed. This concise method allows the rapid formation of a number of oxazolidin-4-ones in high yields with good functional group tolerance at room temperature. Further transformation and late-stage modifications of drug molecules could also be achieved in good yields, highlighting the potential utility of the reaction. [ABSTRACT FROM AUTHOR]

The synthesis, characterization,and reactivity of the monoaryl–Ni(II)compound 2and the diaryl–Ni(II) compound 4formed through the direct electrophilic metalation of twomacrocyclic azacalix[m]arene[n]pyridineligands are described. Compound 4was much more stablein protic solvents and acids than the monoaryl–Ni(II) compound 2. Moreover, 2can react with a variety of nucleophiles,resulting in the formation of C–C, C–O, C–Br,and C–N bonds. In contrast, compound 4exhibitedvery inert reactivity upon reaction with a large numberof nucleophiles.Interestingly, compound 2was also capable of reactingwith several less bulky alkyl halides to form new C–C bonds,while the same procedure is inapplicable to 4. The studyreported in this work provides a thorough investigation on the reactivityof aryl–Ni(II) species that should facilitate comprehensionof the detailed mechanism of nickel-catalyzed C–H functionalization. [ABSTRACT FROM AUTHOR]

A seriesof poly(3-hexylthiophene)-block-polyisoprene (P3HT-b-PI) diblock copolymers (DBCP) and polyisoprene-block-poly(3-hexylthiophene)-block-polyisoprene(PI-b-P3HT-b-PI) triblock copolymers(TBCP) with accurately controlled molecular architecture were synthesizedvia highly efficient coupling reaction between aldehyde end-functionalizedP3HT and living anionic polyisoprene. The self-assembly behaviors,considering morphology and crystallinity, of the thermal annealedbulk samples of these DBCPs and TBCPs containing various PI contentwere systematically investigated. The DBCPs behaved very differentlyfrom most published P3HT BCP systems, showing elongated fibers withpreserved crystallinity regardless of the PI fraction. More noteworthy,with PI fraction less than 40 wt %, the DBCPs exhibited parallel straightfibers longer than several micrometers accompanied by concurrent enhancedcrystallinity. The unique microstructure of the DBCPs might originatefrom moderate microphase separation between P3HT and PI as well ashigh flexibility of PI to conduct the packing of P3HT. The TBCPs,by contrast, exhibited highly curved interdomain boundaries with significantdepressed crystallinity, resembling P3HT diblock copolymers in thestrong phase segregation regime, as more pronounced entanglement ofthe two terminal PI segments would restrict the movement of P3HT. [ABSTRACT FROM AUTHOR]

A facile solution-phase route was developed to synthesize a family of monodisperse Cu2Ge(S3-xSex) alloyed nanocrystals (NCs) with controlled composition across the entire range (0 ≤ x ≤ 3). The band gaps of the resultant NCs can be engineered by tuning the compositions with a nearly linear relationship between them. The band structures of the NCs were studied by cyclic voltammetry and UV-vis absorption spectroscopy. The conducting behavior was revealed to be p-type for these NCs by photoelectrochemical measurements. Their photovoltaic applicability was finally assessed by fabricating solar cells with the Cu2Ge(S2Se) NCs as light harvester and CdS nanorods as electron conducting materials. [ABSTRACT FROM AUTHOR]

We demonstrate that fluorous metal-organic frameworks (FMOFs) are highly hydrophobic porous materials with a high capacity and affinity to C6-C8 hydrocarbons of oil components. FMOF- 1 exhibits rever- sible adsorption with a high capacity for n-hexane, cyclo- hexane, benzene, toluene, and p-xylene, with no detectable water adsorption even at near 100% relative humidity, drastically outperforming activated carbon and zeolite por- ous materials. FMOF-2, obtained from annealing FMOF-1, shows enlarged cages and channels with double toluene adsorption vs FMOF-1 based on crystal structures. The results suggest great promise for FMOFs in applications such as removal of organic pollutants from oil spills or ambient humid air, hydrocarbon storage and transportation, water purification, etc. under practical working conditions. [ABSTRACT FROM AUTHOR]

Drop-shape analysis was used to study the binding of streptavidin to biotin at the interface between water and a pendant chloroform droplet. Polyethylene oxide molecules were synthesized with a hydrophobic tail at one end of the molecule and a hydroxyl or biotin group at the other end. The interfacial tension of the water/chloroform interface was measured before and after addition of these amphiphiles to the chloroform phase and before and after addition of streptavidin to the aqueous phase. The hydroxyl-terminated amphiphiles eliminate nonspecific adsorption of the streptavidin to the interface, while streptavidin binds irreversibly to the biotin-terminated molecules. Molecular interactions within this bound layer were studied by measuring changes in the interfacial pressure as the layer is contracted and expanded by changing the volume of the chloroform droplet. A picture of the interfacial structure was obtained from quantitative comparisons between the experimental results and a molecular theory of protein binding to tethered ligands. These comparisons suggest that protein binding is controlled by the extension of the PEO tethers away from the interface. [ABSTRACT FROM AUTHOR]

Chalcogenide borates have been developed and are considered an attractive system due to their favorable physical properties such as magnetism and nonlinear optical effects. Here, isostructural RE 6 Nb 2 MgSB 8 O 26 (RE = La-Nd) compounds in the title family have been obtained through cation regulation in rare-earth and VB group metals. This family crystalizes in the centrosymmetric P 3̅ space group and features 3D frameworks formed by {[Mg(NbB 4 O 13 ) 2 ] 16- } ∞ polyanionic layers and QRE 6 octahedra. The structural chemistry was characterized and theoretical calculations were performed to understand the structural merit of this family. In addition, RE 6 Nb 2 MgSB 8 O 26 possess the largest band gaps among known rare-earth chalcogenide borates, and they all show antiferromagnetic-like behaviors.

Novel nonlinear optical (NLO) materials possessing simple chemical compositions and facile syntheses are competitive when considering their practical application. Here, a series of ternary selenides Ga x In 2- x Se 3 ( x = 0.07, 0.38, 0.45, and 0.81) that crystallize in a chiral P 6 5 structure are obtained by melting Ga, In, and Se elements. Their three-dimensional structures are built by (Ga/In)Se 4 tetrahedra and InSe 5 trigonal bipyramids. The hexagonal modification's phase stability is analyzed by energy calculation, and their optical band gaps are determined to be 1.72-1.99 eV. They exhibit large NLO responses that are 1.41-1.64 times that of the benchmark AgGaS 2 . The results of density functional theory calculations suggest that introduction of Ga onto the In site in (InSe 4 ) 5- units can form a deformed tetrahedron with more distortion in the structure, and the (InSe 5 ) 7- units contribute a large amount of birefringence to the structure. This work is the first to investigate the ternary chalcogenides M 2 Q 3 (M = Ga or In; Q = S or Se) as new types of infrared NLO crystals with excellent performances, which will stimulate more interest in those possessing simple compositions and outstanding performances.

The balance between second harmonic generation (SHG) intensity and laser-induced damage threshold (LIDT), together with phase-matchable behavior, is the key point for exploration of novel nonlinear optical (NLO) materials. In this work, the NLO property of defect wurtzite-type hexagonal-In 2 Se 3 (γ) is extensively explored first. It exhibits a strong SHG intensity of 2.6 × AgGaS 2 (AGS) at 2.1 μm, and a high powder LIDT of 7.3 × AGS. From wurtzite to γ-In 2 Se 3 , the birefringence changes from 0.003 to 0.075, resulting in the phase-matchable phenomenon of γ-In 2 Se 3 . This is well ascribed to the contribution of the unique InSe 5 unit in γ-In 2 Se 3 from the result of birefringence calculation and analysis.

New compounds with multiple anions are receiving increasing interest in view of their diverse structures and physical properties. Here we report four isostructural hexanary RE 6 Ta 2 MgQB 8 O 26 (RE = Sm, Eu, Gd; Q = S, Se), belonging to the rare chalcogenide borates. Their structures feature an unprecedented [B 4 O 10 ] 8- unit comprised of one BO 4 and three BO 3 units. Their 3D structures are constructed by the connection between QRE 6 octahedra and the ∞ {[Mg(TaB 4 O 13 ) 2 ] 16- } polyanionic layer. Density functional theory calculations on the electronic structure and a birefringence of 4 are also performed.

Quantitative information about protein-ligand interactions is central to drug discovery. To obtain the quintessential reaction dissociation constant, ideally measurements of reactions should be performed without perturbations by molecular labeling or immobilization. The technique of transient induced molecular electrical signal (TIMES) has provided a promising technique to meet such requirements, and its performance in a microfluidic environment further offers the potential for high throughput and reduced consumption of reagents. In this work, we further the development by using integrated TIMES signal (i-TIMES) to greatly enhance the accuracy and reproducibility of the measurement. While the transient response may be of interest, the integrated signal directly measures the total amount of surface charge density resulted from molecules near the surface of electrode. The signals enable quantitative characterization of protein-ligand interactions. We have demonstrated the feasibility of i-TIMES technique using different biomolecules including lysozyme, N , N ', N ″-triacetylchitotriose (TriNAG), aptamer, p -aminobenzamidine (pABA), bovine pancreatic ribonuclease A (RNaseA), and uridine-3'-phosphate (3'UMP). The results show i-TIMES is a simple and accurate technique that can bring tremendous value to drug discovery and research of intermolecular interactions.