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We synthesized a planar macrocyclic dinuclear nickel(II) metallohost from the corresponding macrocyclic imine ligand containing two N 2 O 2 chelate coordination sites and an O 6 cation binding site like 18-crown-6 as well as peripheral hexyl groups. Due to the lipophilic nature of the hexyl groups, the metallohost was soluble in less polar media where its interaction with alkali metal ions was enhanced. The binding studies by NMR spectroscopy clearly showed its strong tendency to form multi-layered structures. The metallohost formed 2 : 1 and 1 : 1 (host/guest) complexes with Na + with the two-step binding constants of logK 1 =6.6 and logK 2 =3.0. In contrast, its complexation with larger alkali metal ions (K + , Rb + , Cs + ) preferentially gave 3 : 2 (host/guest) complexes when 2/3 equiv. of the guest was present. The three-layered structures of these 3 : 2 complexes were well characterized by mass spectrometry and 2D COSY/ROESY experiments as well as DFT calculations, elucidating their unique structural feature with three chemically different environments due to the oppositely curved two [Ni(saloph)] moieties of the metallohost. Therefore, the three-layered structures were preferentially formed when larger alkali metal ions (K + , Rb + , Cs + ) were complexed with the metallohost., (© 2024 Wiley-VCH GmbH.)

Introduction: This study aims to investigate whether the reminiscence bump in older adults' autobiographical memory is influenced by the interviewer's age. Methods: I arranged four interviewer., Conditions: child, university student, middle-aged adult, and older adult. The participating older adults were asked individually to describe three memories and the age at which the event occurred. I analyzed the temporal distribution of the bumps and the recall order., Results: The results indicate that the interviewer's age, especially the child interviewers were influenced the temporal location of the reminiscence bump. Conclusion: This study discusses the implications of these findings for older adults' social communication processes.

Rotaxanes are typically prepared using covalent bonds to trap a wheel component onto an axle molecule, and rotaxane-type wheel-axle assembly using only noncovalent interactions has been far less explored. Here we show that a dinickel(II) metallomacrocycle forms two different types of wheel-axle assemblies with a dibenzylammonium axle molecule based only on noncovalent interactions. The non-threaded assembly was obtained by introduction of Ni 2+ into the macrocycle before the complexation with the axle molecule (metal-first method). The non-threaded assembly was in rapid equilibrium with each of the components in solution. The threaded assembly was obtained by introduction of Ni 2+ after the formation of a pseudorotaxane from the non-metalated wheel and the axle molecule (axle-first method). The threaded assembly was not in equilibrium with the dissociated species even though it was maintained only by noncovalent interactions. Thus, formation of one of the non-threaded and threaded wheel-axle assemblies over the other is governed by the assembly pathway., (© 2024. The Author(s).)

Dynamic M / P invertible helicity was successfully induced at a SiO 2 surface immobilized with a dynamic helical trinuclear cobalt complex, [LCo 3 (NHMe 2 ) 6 ](OTf) 3 , using chiral (( R ) or ( S ))-1-phenylethylamine. Solid-state CD spectra and theoretical calculations suggested that the fixation of the M / P helical complex on the surface via coordination interactions was the key factor of the induced chirality at the surface.

Switching between the formation/dissociation of rotaxanes is important to control the function of various types of rotaxane-based materials. We have developed a convenient and simple strategy, the so-called "accelerator addition", to make a static rotaxane dynamic without apparently affecting the chemical structure. As an interlocked molecule that enables tuning of the formation/dissociation speed, a metallorotaxane was quantitatively generated by the complexation of a triptycene-based dumbbell-shaped mononuclear complex, [PdL 2 ] 2+ (L=2,3-diaminotriptycene), with 27C9. As a result of the inertness of the Pd 2+ -based coordination structure, the metallorotaxane was slowly formed (the static state). This rotaxane formation was accelerated 27 times simply by adding Br - as an accelerator (the dynamic state). A similar drastic acceleration was also demonstrated during the dissociation process when Cs + was added to the metallorotaxane to form the free axle [PdL 2 ] 2+ and the 27C9-Cs + complex., (© 2023 Wiley-VCH GmbH.)

A series of amphiphilic salen complexes, [L1a,bM] and [L2a,bM], were designed and synthesized. These complexes consist of two or four hydrophilic triethylene glycol (TEG) chains and a hydrophobic π-extended metallosalen core based on naphthalene or phenanthrene. The obtained amphiphilic complexes, [L1bM] (M = Ni, Cu, Zn), formed a monolayer at the air-water interface, while the monocationic [L1bCo(MeNH 2 ) 2 ](OTf) did not form a well-defined monolayer. The number of hydrophilic TEG chains also had an influence on the monolayerformation behavior; the tetra-TEG derivatives, [L1bNi] and [L2bNi], showed a pressure rise at a less compressed region than the bis-TEG derivatives, [L1aNi] and [L2aNi]. In addition, the investigation of their compressibility and compression modulus suggested that the tetra-TEG derivatives, [L1bNi] and [L2bNi], are more flexible than the corresponding bis-TEG analogues, [L1aNi] and [L2aNi], and that the phenanthrene derivatives [L1a,bNi] were more rigid than the corresponding naphthalene analogues, [L2a,bNi]. The Langmuir-Blodgett (LB) films of one of the complexes, [L1bNi], showed CD spectra slightly different from that in solution, which may originate from the unique anisotropic environment of the air-water interface. Thus, we demonstrated the possibility of controlling the chiroptical properties of metal complexes by mechanical compression.

Molecular glasses are low-molecular-weight organic compounds that are stable in the amorphous state at room temperature. Herein, we report a state- and water repellency-controllable molecular glass by n -alkane guest vapors. We observed that a macrocyclic host compound pillar[5]arene with the C 2 F 5 fluoroalkyl groups changes from the crystalline to the amorphous state (molecular glass) by heating above its melting point and then cooling to room temperature. The pillar[5]arene molecular glass shows reversible transitions between amorphous and crystalline states by uptake and release of the n -alkane guest vapors, respectively. Furthermore, the n -alkane guest vapor-induced reversible changes in the water contact angle were also observed: water contact angles increased and then reverted back to the original state by the uptake and release of the n -alkane guest vapors, respectively, along with the changes in the chemical structure and roughness on the surface of the molecular glass. The water repellency of the molecular glass could be controlled by tuning the uptake ratio of the n -alkane guest vapor., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

SignificanceWe first observed a transient chirality inversion on a simple unimolecular platform during the racemization of a chiral helical complex [LCo 3 A 6 ] 3+ , i.e., the helicity changed from P -rich (right-handed) to M -rich (left-handed), which then racemized to a P / M equimolar mixture in spite of the absence of a reagent that could induce the M helix. This transient chirality inversion was observed only in the forward reaction, whereas the reverse reaction showed a simple monotonic change with an induction time. Consequently, the M helicity appeared only in the forward reaction. These forward and reverse reactions constitute a hysteretic cycle. Compounds showing such unique time responses would be useful for developing time-programmable switchable materials that can control the physical/chemical properties in a time-dependent manner.

The reaction of calix[4]arene derivatives 1a and 1b bearing four salicylaldehyde moieties with 1,3-propanediamine gave macrocyclic trimers 5a and 5b, respectively, which have intramolecular bridges formed via the flattened cone conformation. In contrast, a capsular-shaped dimeric cage [7a·2Na] 2+ was selectively formed when the conformation of the calix[4]arene moiety of 1a was fixed in the spread cone conformation by complexation with Na + at the lower-rim amide groups.

Unique bench-stable rhodium(I) complexes bearing an aryl-substituted 1,3,5-hexatriene chain have been synthesized by reactions of (bicyclo[2.2.1]hepta-2,5-diene)rhodium(I) chloride dimer ([Rh(nbd)Cl] 2 ) with aryl boronic acids and diphenylacetylenes in the presence of a 50 % aqueous solution of KOH. X-ray crystallographic analysis of the isolated complexes indicated a square-planar structure stabilized by a strong interaction with one of the aryl groups on the 1,3,5-hexatriene chain, which has a helical structure. The helical chirality of the isolated rhodium complexes was confirmed to be sufficiently stable to be resolved into enantiomers by HPLC on a chiral stationary phase at room temperature. It was confirmed that the isolated rhodium complexes functioned as initiators for living polymerization of phenylacetylene to give cis-stereoregular poly(phenylacetylene) with a well-controlled molecular weight., (© 2021 Wiley-VCH GmbH.)

We have designed a new chiral receptor based on two salen zinc(ii) complex units connected with a spirobifluorene framework. The chiral receptor is proven to enantioselectively bind chiral carboxylate guests and the differences between the binding constants of enantiomeric guests were up to more than one order of magnitude.

Host-guest binding behavior of macrocyclic hosts is significantly influenced by the shapes and sizes of the hosts. In particular, closing/opening the apertures of the hosts controls the guest uptake/release. A post-metalation modification method was used to achieve the open/close conversions. The starting open complex, [LCo 2 (pip) 4 ](OTf) 2 , was efficiently converted to the closed complex, [LCo 2 (hda) 2 ](OTf) 2 , which has a doubly bridged structure. The conversion of this closed complex to the open complex [LCo 2 (hda) 2 (OAc)] + was too slow to be completed, but this gate-opening was dramatically accelerated by the addition of Na + . The Na + binding was also significantly enhanced by the gate-opening, that is, conversion of [LCo 2 (hda) 2 ] 2+ to [LCo 2 (hda) 2 (OAc)] + ., (© 2020 Wiley-VCH GmbH.)

A novel cooperative [3]pseudorotaxane system consisting of dibenzo-24-crown-8 (DB24C8) and diphenylviologen axle has been developed. The two-step formation of the [3]pseudorotaxane occurred in a positive-cooperative manner. The corresponding [3]rotaxane was successfully obtained from just a stoichiometric mixture of each component by end-capping without dissociation.

We propose post-metalation modification as a useful strategy to control the guest recognition behavior of a metal-containing macrocyclic host. This is based on the ligand exchange of the axial ligands of a cobalt(III) dinuclear macrocyclic host, [LCo 2 X 4 ] 2+ (X=axial amine ligand). Four piperidine ligands in [LCo 2 (pip) 4 ] 2+ (pip=piperidine) were site-selectively replaced with primary amines. The competitive experiments revealed that the order of the affinity toward the cobalt centers in [LCo 2 X 4 ] 2+ is primary amine > secondary amine > tertiary amine and that the piperidine-coordinating complex, [LCo 2 (pip) 4 ] 2+ , was reasonably reactive among the isolable complexes. Indeed, two piperidine ligands at the diagonal positions in [LCo 2 (pip) 4 ] 2+ were site-selectively replaced with pyridine or acetate ion. The replacement of piperidine with acetate ion significantly enhanced the recognition ability towards Na + ., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Supramolecular chemistry in confined spaces constructed from macrocyclic molecules has attracted much attention because it can utilize the specific binding properties of macrocyclic cavities. Herein we report the preparation of length-controlled discrete tubular structures by homo-/co-assembly of rim-differentiated and peralkylamino-substituted pillar[5]arenes via hydrogen bonds and salt bridges. By dimerization and trimerization, the expanded tubes show a fivefold helical structure and stepwise binding, respectively. We found that the exchange speed of guest molecules in the tubes could be controlled by varying the tube length., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Diuranyl bis(salophen) complex 1 features a relatively slow conformational motion, induced by an intramolecular O═U═O···UO 2 binding motif, which interconverts the two nonsymmetric halves of the ligand. This flipping motion, which constitutes one of the fundamental molecular motions, can be completely halted by addition of fluoride anion, which is bound to 1 , reaching one of the highest affinities reported to date. This system represents a model to study flipping dynamics in light of the possibility of developing novel types of molecular machines based on it.

Host-guest binding sometimes triggers the subsequent chemical reactions of the host framework as well as changes in the physical properties. Since the host-guest binding generally occurs very quickly, it is sometimes difficult to differentiate the mechanism from the alternative one in which the guest binding occurs after the reaction. However, it is important to differentiate the two mechanisms when we develop new molecules based on time-dependent functions. Thus, we propose two distinct mechanisms, recognition first and reaction first , in a slowly reacting host system. We designed and synthesized a new cobalt(III) metallohost, [LCo 2 (pip) 4 ](OTf) 2 (pip = piperidine), which can take up a guest cation into its 18-crown-6-like cavity causing concomitant exchange of the axial piperidine ligands under solvolytic conditions. We investigated the mechanism to elucidate whether the guest recognition or ligand exchange occurs first. When Na + (5-10 equiv) was present, the guest recognition occurred by the recognition first mechanism; i.e., Na + was initially taken up into the cavity, then the axial piperidine ligands were replaced with methoxo ligands. On the other hand, when 1 equiv of M + (= K + , Rb + ) was present, the guest recognition occurred by the reaction first mechanism; i.e., M + was taken up after one of the piperidine ligands was replaced with a methoxo ligand. Therefore, the recognition pathway can be switched by changing the guest cations.

We developed a new strategy, ligand exchange strategy, for tuning the response speeds of helicity inversion of a metal-containing helical structure. This is based on the exchange of the two axial amine ligands of the octahedral Co 3+ centers in the metallocryptands [LCo 3 X 6 ] (X=axial amine ligand). The response speeds of the helicity induction were controlled by using different combinations of achiral and chiral amines as the starting and entering ligands, respectively. The response speeds of the helicity inversion from P to M were also tuned by using different combinations of chiral amines., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Host-guest complexation has been mainly investigated in solution, and it is unclear how guest molecules access the assembled structures of host and dynamics of guest molecules in the crystal state. In this study, we studied the uptake, release, and molecular dynamics of n-hexane vapor in the crystal state of pillar[5]arenes bearing different substituents. Pillar[5]arene bearing 10 ethyl groups yielded a crystal structure of herringbone-type 1:1 complexes with n-hexane, whereas pillar[5]arene with 10 allyl groups formed 1:1 complexes featuring a one-dimensional (1D) channel structure. For pillar[5]arene bearing 10 benzyl groups, one molecule of n-hexane was located in the cavity of pillar[5]arene, and another n-hexane molecule was located outside of the cavity between two pillar[5]arenes. The substituent-dependent differences in molecular arrangement influenced the uptake, release, and molecular dynamics of the n-hexane guest. The substituent effects were not observed in host-guest chemistry in solution, and these features are unique for the crystal state host-guest chemistry of pillar[5]arenes., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Confinement of polymers in nano-spaces can induce unique molecular dynamics and properties. Here we show molecular weight fractionation by the confinement of single polymer chains of poly(ethylene oxide) (PEO) in the one-dimensional (1D) channels of crystalline pillar[5]arene. Pillar[5]arene crystals are activated by heating under reduced pressure. The activated crystals are immersed in melted PEO, causing the crystals to selectively take up PEO with high mass fraction. The high mass fractionation is caused by the greater number of attractive CH/π interactions between PEO C-H groups and the π-electron-rich 1D channel of the pillar[5]arene with increasing PEO chain length. The molecular motion of the confined PEO (PEO chain thickness of ~3.7 Å) in the 1D channel of pillar[5]arenes (diameter of ~4.7 Å) is highly restricted compared with that of neat PEO.

A triptycene-based shape-persistent belt-shaped macrocycle, metallonanobelt, was synthesized by the self-assembly of 2,3,6,7-tetraaminotriptycene L and square planar Pd 2+ . The pentamer was selectively formed by the complexation of L with Pd 2+ in the presence of the pillar[6]arene derivative P6 having triethylene glycol pendant as a template, whereas a mixture of a trimer, tetramer, and pentamer was obtained in the absence of the template. The pentamer was successfully isolated based on the solubility difference between the metallonanobelt and the template. It was also revealed that the isolated pentamer was remarkably stable in solutions such as acetonitrile or methanol thanks to the relatively inert planar chelate metal complex, [Pd( o-phenylenediamine) 2 ] unit. Thus, we can handle the metallonanobelt almost as a static organic nanobelt that is synthesized covalently.

To analyze the structure and function of phytochrome chromophores, we have been synthesizing natural and unnatural bilin chromophores of phytochromes. In this manuscript, we report the synthesis of sterically fixed 15 E- fixed 18Et-biliverdin (BV) and 15 E- anti-fixed 18Et-BV derivatives. The key reaction is the introduction of an sp 3 carbon alkyl chain bearing a leaving group at the meso-position of the CD-ring component by using the corresponding Grignard reagents in the presence of LiCl.

A (μ-peroxo)diiron(iii) complex [Fe 2 (L Ph 4 )(O 2 )(Ph 3 CCO 2 )] 2+ (1-O 2 ) with a dinucleating ligand (L Ph 4 ), generated from the reaction of a carboxylate bridged diiron(ii) complex [Fe 2 (L Ph 4 )(Ph 3 CCO 2 )] 2+ (1) with dioxygen in CH 2 Cl 2 , provides a diiron(iv)-oxo species as an active oxidant which is involved in either aromatic ligand hydroxylation or benzyl alcohol oxidation.

We report a simple and easy-to-operate method for separating n-alkanes: when we immersed activated pillar[5]arene crystals into a mixture of n-alkanes with various chain lengths, the crystals preferentially took up n-alkanes with longer chain lengths.

The switching of molecular recognition selectivity is important for tuning molecular functions based on host-guest binding. While the switching processes in artificial functional molecules are usually driven by changes of the thermodynamic stabilities, non-equilibrium phenomena also play an important role in biological systems. Thus, here we designed a host-guest system utilizing a non-equilibrium kinetically trapped state for on-demand and time-programmable control of molecular functions. We synthesized a bis(saloph) macrocyclic cobalt(III) metallohost 1(OTf) 2 , which has anion caps at both sides of the cation-binding site. The anion caps effectively retard the guest uptake/release so that we can easily make a non-equilibrium kinetically trapped state. Indeed, we can obtain a long-lived kinetically trapped state {[1·K] 3+ +La 3+ } prior to the formation of the thermodynamically more stable state {[1·La] 5+ +K + }. The guest exchange to the more stable state from this kinetically trapped state is significantly accelerated by exchange of TfO - anion caps by AcO - in an on-demand manner.

Precise modulation of cation binding affinity was accomplished by the efficient two-step conversion of a newly synthesized macrocyclic ligand H 4 L 2 having a 24-crown-8-like cavity and two saloph moieties. The conversion of H 4 L 2 into L 2 Ni 2 resulted in a 120-fold enhancement in the binding affinity towards Cs + . The electrochemical reduction of L 2 Ni 2 further enhanced the recognition ability by 3 orders of magnitude.

A one-pot synthetic method was developed for multifunctional dihydrooxazole and oxazole derivatives. New reaction sequences were developed involving the formation of isocyanide dichloride, an aldol-type reaction with aldehydes, and a nucleophilic addition-elimination reaction, which efficiently afforded the dihydrooxazole and oxazole scaffolds.

Colored crystals of pillar[5]arene containing one benzoquinone unit were found to exhibit alkane-shape-selective vapochromic behavior. Activated pillar[5]arene crystals, prepared by removing solvated methanol from pillar[5]arene crystals, changed color from dark-brown to light-red after exposure to linear alkane vapors; however, no color changes were observed on exposure to branched or cyclic alkanes. Uptake of methanol vapor by the activated crystals induced a different color change, from dark-brown to black. This multi-vapochromism results from the different intermolecular π-stacking interactions between the benzoquinone and 1,4-diethoxybenzene units in the alkane- and methanol-containing crystals. Unlike most known vapochromic materials, these pillar[5]arene-based materials were highly stable; after uptake of n-alkanes or methanol the color of the crystals did not change after storage in air for 3 weeks. This is because the included guests were stabilized in the cavity by multiple CH/π interactions.

The Dimensional Change Card Sort (DCCS) task is a widely used measure for the development of executive function during early childhood. In this task, children are asked to sort cards according to one rule (e.g., color) during preswitch phases, after which they are asked to sort cards according to another rule (e.g.; shape) during the postswitch phases. A computer version of the DCCS was needed to standardize the test material, but a previous study showed that children showed more difficulty in a computer version with a mouse device than the standard card version. In this study, we assessed the effectiveness of a computer version with a touch panel and compared performance with the standard card version. Three- and 4-year-old children were given the card version and computer version of the DCCS tasks. The results revealed that children showed similar performance during the preswitch and postswitch phases both in the computer version and in the card version. The results suggest that both versions of the task assessed the same underlying cognitive processes.

A newly synthesized dipyrrinone derivative bearing an ethoxycarbonyl group at the pyrrolic-α position exhibited solvent-dependent dual-mode photochromism between T- and P-types. While this molecule underwent thermally reversible (T-type) photoresponsive reaction in chloroform, it became a thermally irreversible (P-type) system in methanol.

The reaction of (Z)-hydroximoyl chlorides with isocyanides promoted by phosphinic acid in the presence of triethylamine proceeds smoothly to afford α-(hydroxyimino)amides in good to high yields. Phosphinic acid plays an important role in effectively promoting the reaction. A wide range of (Z)-hydroximoyl chlorides and isocyanides were found to be suitable for this reaction.

(μ-1,2-Peroxo)diiron(iii) complexes (-R) with dinucleating ligands (R-L) generated from the reaction of bis(μ-hydroxo)diiron(ii) complexes [Fe2(R-L)(OH)2](2+) (-R) with dioxygen in acetone at -20 °C provide a diiron-centred electrophilic oxidant, presumably diiron(iv)-oxo species, which is involved in aromatic ligand hydroxylation.

Activated perethylated pillar[5]arene crystals show an unexpected alkane-shape- and -length-selective gate-opening behavior. Activated crystals were obtained upon removing solvents from perethylated pillar[5]arene crystals by heating. The activated crystals could quantitatively take up n-alkanes with carbon chains containing more than five carbon atoms as a consequence of their gate-opening pressure. As the chain length of the n-alkanes increased, the gate pressure decreased. A transformation into a herringbone structure was induced when n-hexane was used as a guest. By contrast, cyclic and branched alkanes were not taken up and could not induce a crystal transformation because they were too large to fit in the cavities of the pillar[5]arene. Alkane-shape-selective molecular recognition of pillar[5]arenes in the solution state was translated into the vapor/crystal state., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Intervention of executive function during early childhood is an important research topic. This study examined the effect of a child-friendly intervention program, where children interacted with a doll or a puppet. Children were presented with cognitive shifting tasks before and after an intervention. In the intervention, children interacted with a doll or a puppet, and taught rules of the cognitive shifting tasks to the object. As the results, 3- to 5-year-old children significantly improved the performances and strengthened activations in the lateral prefrontal regions as measured by near-infrared spectroscopy. The results suggest that interaction with a doll or a puppet may have a significant impact on the development of executive function.

In tauopathies, a neural microtubule-associated protein tau (MAPT) is abnormally aggregated and forms neurofibrillary tangle. Therefore, inhibition of the tau aggregation is one of the key approaches for the treatment of these diseases. Here, we have identified a novel tau aggregation inhibitor, PE859. An oral administration of PE859 resulted in the significant reduction of sarkosyl-insoluble aggregated tau along with the prevention of onset and progression of the motor dysfunction in JNPL3 P301L-mutated human tau transgenic mice. These results suggest that PE859 is useful for the treatment of tauopathies.

Structural transformability accompanied by molecular accommodation is a distinguished feature of porous coordination polymers (PCPs) among porous materials. Conventional X-ray crystallography allows for the determination of each structural phase emerged during transformation. However, the propagation mechanism of transformation through an entire crystal still remains in question. Here we elucidate the structural nature of the spatial transient state, in which two different but correlated framework structures, an original phase and a deformed phase, simultaneously exist in one crystal. The deformed phase is distinctively generated only at the crystal surface region by introducing large guest molecules, while the remaining part of crystal containing small molecules maintains the original phase. By means of grazing incidence diffraction techniques we determine that the framework is sheared with sharing one edge of the original primitive cubic structure, leading to the formation of crystal domains with four mirror image relationships.

Hybridized porous coordination polymers (PCPs) are synthesized through epitaxial growth or ligand replacement. Whereas epitaxial growth on the core crystal leads to a sandwich type PCP, ligand replacement near the surface of core crystal results in a core-shell type PCP.

Flexible porous coordination polymers change their structure in response to molecular incorporation but recover their original configuration after the guest has been removed. We demonstrated that the crystal downsizing of twofold interpenetrated frameworks of [Cu(2)(dicarboxylate)(2)(amine)](n) regulates the structural flexibility and induces a shape-memory effect in the coordination frameworks. In addition to the two structures that contribute to the sorption process (that is, a nonporous closed phase and a guest-included open phase), we isolated an unusual, metastable open dried phase when downsizing the crystals to the mesoscale, and the closed phase was recovered by thermal treatment. Crystal downsizing suppressed the structural mobility and stabilized the open dried phase. The successful isolation of two interconvertible empty phases, the closed phase and the open dried phase, provided switchable sorption properties with or without gate-opening behavior.

Spatiospecific functionalisation of a shell crystal was performed in a core-shell crystal of a porous coordination polymer (PCP) via post-synthetic modification (PSM). The shell crystal allowed the core crystal to selectively accumulate N,N-dimethylaniline (DMA) and afford the intense exciplex fluorescence.

A series of benzo[b]furan derivatives having a five-membered heterocyclic substituent at the 2-position were prepared from 2-(1-chloro-2-formylvinyl)benzo[b]furans (2) and 2-(4-alkylcarbamoylbuta-1,3-dienyl)benzo[b]furans. These 2-heterocyclic benzo[b]furans were evaluated for their cysteinyl leukotriene receptor (cysLT1, cysLT2) inhibitory activity. Several compounds showed moderate inhibition of calcium mobilization in HEK 293T-cysLT2 or CHO-cysLT1 cells.

A series of heteroleptic [Ti1(2)X](-) complexes have been selectively constructed from a mixture of Ti(IV) ions, a pyridyl catechol ligand (H(2)1; H(2)1=4-(3-pyridyl)catechol), and various bidentate ligands (HX) in the presence of a weak base, in addition to a previously reported [Ti1(2)(acac)](-) (acac=acetylacetonate) complex. Comparative studies of these Ti(IV) complexes revealed that [Ti1(2)(trop)](-) (trop=tropolonate) is much more stable than the [Ti1(2)(acac)](-) complex, which allows the replacement of acac with trop on the [Ti1(2)(acac)](-) complex. This Ti(IV)-centered site-selective ligand exchange reaction also takes place on a heteronuclear Pd(II)-Ti(IV) ring complex with the preservation of the Pd(II)-centered coordination structures. Intra- and intermolecular linking between two Ti(IV) centers with a flexible or a rigid bis-tropolone bridging ligand provided a tetranuclear and an octanuclear Pd(II)-Ti(IV) complex, respectively. These higher-order structures could be efficiently constructed only through a stepwise synthetic route.

A series of 2-(2-aminothiazol-4-yl)benzo[b]furan and 3-(2-aminothiazol-4-yl)benzo[b]furan derivatives were prepared, and their leukotriene B(4) inhibitory activity and growth inhibitory activity in cancer cell lines were evaluated. Several compounds showed strong inhibition of calcium mobilization in CHO cells overexpressing human BLT(1) and BLT(2) receptors and growth inhibition to human pancreatic cancer cells MIA PaCa-2. 3-(4-Chlorophenyl)-2-[5-formyl-2-[(dimethylamino)methyleneamino]thiazol-4-yl]-5-methoxybenzo[b]furan 8b showed the most potent and selective inhibition for the human BLT(2) receptor, and its IC(50) value was smaller than that of the selected positive control compound, ZK-158252. 3-(4-Chlorophenyl)-2-[2-[(dimethylamino)methyleneamino]-5-(2-hydroxyethyliminomethyl)thiazol-4-yl]-5-methoxybenzo[b]furan 9a displayed growth inhibitory activity towards MIA PaCa-2.

Heteronuclear, supramolecular ring and cage complexes have been constructed from a pyridyl catechol ligand, TiO(acac)2, and PdCl2(CH3CN)2. These two complexes are quantitatively interconvertible, in which Ti4+-centered coordination changes take place between a well-known Ti(catecholato)3 and a newly established TiH(catecholato)2(acetylacetonato) structures. The Ti4+-centered structural changes arise from the changes in the component fraction and basicity condition.

A number of fish species receive forebrain cholinergic input but two recent reports failed to find evidence of cholinergic cell bodies or fibers in the olfactory bulbs (OBs) of zebrafish. In the current study we sought to confirm these findings by examining the OBs of adult zebrafish for choline acetyltransferase (ChAT) immunoreactivity. We observed a diffuse network of varicose ChAT-positive fibers associated with the nervus terminalis ganglion innervating the mitral cell/glomerular layer (MC/GL). The highest density of these fibers occurred in the anterior region of the bulb. The cellular targets of this cholinergic input were identified by exposing isolated OBs to acetylcholine receptor (AChR) agonists in the presence of agmatine (AGB), a cationic probe that permeates some active ion channels. Nicotine (50 microM) significantly increased the activity-dependent labeling of mitral cells and juxtaglomerular cells but not of tyrosine hydroxlase-positive dopaminergic neurons (TH(+) cells) compared to control preparations. The nAChR antagonist mecamylamine, an alpha7-nAChR subunit-specific antagonist, calcium-free artificial cerebrospinal fluid, or a cocktail of ionotropic glutamate receptor (iGluR) antagonists each blocked nicotine-stimulated labeling, suggesting that AGB does not enter the labeled neurons through activated nAChRs but rather through activated iGluRs following ACh-stimulated glutamate release. Deafferentation of OBs did not eliminate nicotine-stimulated labeling, suggesting that cholinergic input is primarily acting on bulbar neurons. These findings confirm the presence of a functioning cholinergic system in the zebrafish OB.

A series of 3-(4-chlorophenyl)-2-(2-aminothiazol-4-yl)benzo[b]furan derivatives 6-10 were prepared and their leukotriene B(4) inhibitory activity was evaluated. We found that several compounds showed strong inhibition of calcium mobilization in CHO cells overexpressing human BLT(1) and BLT(2) receptors. Among them, 3-(4-chlorophenyl)-2-[5-formyl-2-[(dimethylamino)methyleneamino]thiazol-4-yl]-5-methoxybenzo[b]furan 9b showed the most potent and selective inhibition for the human BLT(2) receptor, and its IC(50) value was smaller than that of the selected positive control compound, ZK-158252.

Since glycosidase and glycosyltransferase inhibitors, composed of carba-sugars, have recently attracted much attention, it is desirable to develop effective preparative routes for provision of new carba-sugar derivatives of potential biological interest. 1,2:3,6-Dianhydro-5a-carba-alpha-glucopyranose was here chosen for study of synthetic utility, and demonstrated to be a promising intermediate for supplying several carba-beta-glycosylamines and N-linked dicarba-oligosaccharides. An N-linked 5a,5a'-dicarbalactose derivative obtained here was found to be a strong alpha-galactosidase inhibitor (IC50 1.2 microM, green coffee beans).

The authors examined age-related differences in target discrimination before the saccade to investigate the influence of aging on the facilitation of target discrimination by shifts of attention. Older and younger adults made saccades toward a peripheral stimulus after its onset and discriminated the orientation of the stimulus. Mean saccadic latency was greater for older adults than for younger adults. Facilitation of target discrimination immediately before the saccades was found both in older and younger adults. These results suggest that aging affects the properties of saccades but does not affect the properties of attentional shifts immediately before a saccade.

Olfactory coding at the level of the olfactory bulb is thought to depend upon an ensemble response of mitral cells receiving input from chemotopically-organized projections of olfactory sensory neurons and regulated by lateral inhibitory circuits. Immunocytochemical methods are described to metabolically classify neurons in the developing zebrafish olfactory system based on the relative concentrations of taurine, glutamate, GABA (and potentially other small biogenic amines) and a small guanidium-based cation, agmatine, which labels NMDA-sensitive cells by permeating through active ionotropic glutamate receptor channels. Using metabolic profiling in conjunction with activity dependent labeling we demonstrate that neuronal differentiation in the developing olfactory bulb, as assessed by acquisition of a mature neurochemical profile, and sensitivity to an ionotropic glutamate receptor agonist, NMDA, occurs during the second day of development. This experimental approach is likely to be useful in studies concerned with the development of glutamatergic signaling pathways.

Goatfish use a pair of large chin barbels to probe the sea bottom to detect buried prey. The barbels are studded with taste buds but little else is known about the neural organization of this system. We found that the taste buds of the barbel are innervated in a strict orthogonal fashion. The barbel is innervated by a main nerve trunk running in the core of the barbel. A longitudinal nerve bundle originates from the main trunk and, after running a short distance distally, divides into two circumferential nerve bundles (CNB) extending respectively, medially and laterally around the barbel. Approximately 15 CNBs innervate each 1 mm length of barbel. At each transverse level, the CNB innervates two clusters of taste buds, each containing 14 end-organs. The primary taste centre in the brain is similarly extraordinary. The sensory inputs from the barbel terminate in a derived dorsal facial lobe, which has a highly convoluted surface forming a multitude of tubercles. Electrophysiological mapping experiments show that the entire barbel is somatotopically represented in a recurved elongate tubular fashion within the dorsal facial lobe.