Dimeric capsules with a nanoscale cavity for [60]fullerene encapsulation

The acid-assisted and guest-induced formation of superstructures was achieved by the addition of haloacetic acids to a toluene solution of the resorcin[4]arene derivatives 1 and [60]fullerenes. The formation of dimeric superstructures that encapsulated a nanosized guest molecule was observed when appropriate acids, such as haloacetic acids, and suitable guest molecules, such as [60]fullerenes, were co-added to a toluene solution of cavitand 1 that has four pyridine units, whereas a complicated equilibrium between several species was detected without [60]fullerenes, and the formation of discrete superstructures was not monitored in the absence of haloacetic acids. The spectroscopic data indicate that the formed [60]fullerene-encapsulated complexes have the structure of 2. These complexes are self-assembled through pyridinium-anion-pyridinium interactions and by pi-pi and van der Waals interactions. The rate of decomplexation of 2 is estimated to be 3.1 s(-1) from a 2D exchange NMR spectrum. The [60]fullerene encapsulation process can be controlled by modifying the amounts of acids used, changing the temperature of the system, altering the ratio of acid/base, and even through varying the solvent polarity. Moreover, the fluorescence spectra show band-narrowing spectral changes and a retardation of the relaxation characteristics of isolated and isotropic [60]fullerenes, which indicates that the environmental change around [60]fullerene is induced upon its encapsulation.     

Phosphorescent thymidine triphosphate sensor based on a donor-acceptor ensemble system using intermolecular energy transfer

An ensemble sensor system that exhibited selective luminescence enhancement upon binding to thymidine 5'-triphosphate (TTP) in HEPES buffer over other nucleotides was developed. The ensemble system consisted of an energy acceptor (FIrpic-bis(Zn2+-dipicolylamine conjugate, FIrpic=bis[(4,6-difluorophenyl)-pyridinato-N,C2+]picolinate) derivative) and an energy donor (mCP-Zn2+-cyclen, mCP=N,N'-dicarbazolyl-3,5-benzene). Among the nucleotides, the selective recognition and luminescence enhancement for TTP was achieved by the strong binding of the thymine unit to Zn2+-cyclen (cyclen=1,4,7,10-tetraazacyclododecane) and intermolecular energy transfer between the mCP and FIrpic moieties.     

Determination of analogs of sildenafil and vardenafil in foods by column liquid chromatography with a photodiode array detector, mass spectrometry, and nuclear magnetic resonance spectrometry

Two analogs of sildenafil and vardenafil in food were detected by column liquid chromatography (LC) with a photodiode array detector. They were isolated by preparative LC; their structures were established by mass spectrometry and nuclear magnetic resonance spectrometry. One analog was found to be methisosildenafil (compound A), 5-(5-(3,5-dimethylpiperazin-1-ylsulfonyl)-2-ethoxy-phenyl)-1-methyl-3-propyl-1H-pyrazolo[4,3-d]-pyrimidin-7(6H)-one. It is a sildenafil analog with a dimethylpiperazine ring substituted for the methylpiperazine group. The second analog, hydroxyvardenafil (compound B) is reported for the first time in this study. Hydroxyvardenafil's International Union of Pure and Applied Chemistry name is 2-(2-ethoxy-5-(4-(2-hydroxyethyl)-piperazin-1-ylsulfonyl)phenyl)-5-methyl-7-propyl-imidazo[1,5-f][1,2,4]triazin-4(3H)-one. The novel vardenafil analog has a hydroxyl group added to the ethylpiperazine group.     

Transient phosphorylation of tumor associated microtubule associated protein (TMAP)/cytoskeleton associated protein 2 (CKAP2) at Thr-596 during early phases of mitosis

Tumor associated microtubule associated protein (TMAP), also known as cytoskeleton associated protein 2 (CKAP2) is a mitotic spindle-associated protein whose expression is cell cycle-regulated and also frequently deregulated in cancer cells. Two monoclonal antibodies (mAbs) against TMAP/CKAP2 were produced: B-1-13 and D-12-3. Interestingly, the reactivity of mAb D-12-3 to TMAP/CKAP2 was markedly decreased specifically in mitotic cell lysate. The epitope mapping study showed that mAb D-12-3 recognizes the amino acid sequence between 569 and 625 and that phosphorylation at T596 completely abolishes the reactivity of the antibody, suggesting that the differential reactivity originates from the phosphorylation status at T596. Immunofluorescence staining showed that mAb D-12-3 fails to detect TMAP/CKAP2 in mitotic cells between prophase and metaphase, but the staining becomes evident again in anaphase, suggesting that phosphorylation at T596 occurs transiently during early phases of mitosis. These results suggest that the cellular functions of TMAP/CKAP2 might be regulated by timely phosphorylation and dephosphorylation during the course of mitosis.     

Mesoporous Titania Thin Film with Highly Ordered and Fully Accessible Vertical Pores and Crystalline Walls

We report the preparation of mesoporous titania thin films with the R m pore structure derived from the Im m self‐assembled ordering of the titania species and an EO₁₀₆PO₇₀EO₁₀₆ triblock copolymer. The films were spin‐cast and then aged at 18 °C at a relative humidity of 70 %, which led to the orientation of the Im m structure with the [111] direction perpendicular to the substrates. The [111] body‐diagonal channels became vertical channels upon calcination at 400 °C, thus leading to thin films with vertical channels. The pores are ordered over a large area of up to 1 μm². The titania films can be formed on various types of substrates. By using a titania film formed on a Pt‐coated Si wafer as a template, we produced by an electrochemical‐deposition technique arrays of gold nanowires, whose morphology suggests that most of the pores of the titania thin films are accessible. The pore structure of vertical channels is stable up to 600 °C, at which temperature the wall materials crystallize into anatase.     

Dibromido(dimethyl sulfoxide‐κO)(1,10‐phenanthroline‐κ2N,N′)copper(II)

The solvent effect on the molecular structures of copper(II) complexes produced from the reaction between CuBr₂ and 1,10‐phenanthroline is evident. The momomeric title compound, [CuBr₂(C₁₂H₈N₂)(C₂H₆OS)], which consists of discrete units, is produced from this reaction in dimethyl sulfoxide (DMSO), whereas a polymeric copper(II) compound is known to be produced from the same reaction in the poor coordinating solvent ethanol. The geometry around the copper(II) ion in the title compound is best described as trigonal–bipyramidal distorted square‐based pyramidal, with a τ value of 0.37. The two phenanthroline N atoms, the DMSO O atom and one of the Br atoms occupy the four basal positions, while the second Br atom occupies the axial position. The magnetic susceptibility data also indicate that the title compound is monomeric, but there is still a weak antiferromagnetic interaction between paramagnetic copper(II) centers via the intermolecular `Cu—Br...Br—Cu' contact pathway.     

Quantities equivalent to the norm of a weighted Bergman space

Let 0?α<∞, 0<p<∞, and p−α>−2. If f is holomorphic in the unit disc D and if ω is a radial weight function of secure type, then the followings are equivalent:

     

A Mesoporous Silica Thin Film as Uptake Host for Guest Molecules with Retarded Release Kinetics

Uptake and release processes of various fluorescent rhodamine dyes and antitumor drugs to/from an ordered mesoporous silica film are investigated by means of UV/Vis absorption and fluorescence spectroscopies. The pores in the 160 nm‐thick silica film strongly withdraw the dyes from water, thus allowing the storage of several micrograms of guest molecules per square centimeter of film. The binding equilibrium of the dyes follows a Langmuir‐type adsorption. The dissociation constant, K_d, and the maximum binding amount to the film, , are determined by fitting the binding curves. The release kinetics of the guests from the film to a simulated body fluid (SBF) solution follows a bimodal first‐order exponential behavior. The release kinetics from the mesoporous thin film is remarkably retarded relative to that from mesoporous powders. Among all the studied dyes, rhodamine 101 is released most slowly, which implies that the release rate depends not only on the interactions between the guests and the silica surface, but also on intermolecular interactions between the guest molecules. Comparison of the release kinetics of different antitumor drugs, such as actinomycin D and mitoxantrone, into an SBF solution shows that mitoxantrone is released much slowly. This slower release is attributed to the positive molecular charge and the formation of dimers in the pores.     

Combination effects of cation and anion of ionic liquids on the cadmium metal-organic frameworks in ionothermal systems

The effects of cation and/or anion of two groups of ionic liquids ([EMI]X and [PMI]X, where EMI = 1-ethyl-3-methylimidazolium; PMI = 1-propyl-3-methylimidazolium; X = Cl, Br, and I) on the ionothermal reactions between Cd(NO 3) 2.4H 2O and 1,3,5-benzenetricarboxylic acid (H 3BTC) were studied. Three different Cd-BTC metal-organic frameworks, [EMI][Cd2(BTC)Cl2](1), [EMI][Cd(BTC)](2), and [PMI][Cd(BTC)](3), were formed into crystalline phases. 1 was obtained from reactions in [EMI]Cl, while the same reactions with Cl replaced by Br or I produced a known compound 2. The replacement of EMI(+) by PMI(+) produced 3, irrespective of the nature of X.