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International audience; Silicificated self-organised crystalline bilayers of gemini surfactants were used as reaction templates for supramolecular regioselective [4+4] photocyclodimerisation of 2-anthracenecarboxylate in water. Near perfect head-to-head cyclodimers selectivity, up to 97% at room temperature was achieved with accelerated dimerisation. Ever since the first report in 1867, 1-3 the [4+4] photocyclodimerisation of anthracene and its derivatives has attracted much attention due to the unique structure and properties of the photocyclodimers obtained, and has been employed indeed as a key motif in energy storage and photoreversible devices. 4-8 However, controlling regio-and enantioselectivities of the photocyclodimerisation of anthracene derivatives, such as 2anthracenecarboxylate (AC) (Scheme 1), is a challenge, which has driven researchers to the use of supramolecular approach, 9,10 using cyclodextrins, 11-14 proteins, 15,16 molecular templates, 17-21 molecular cages, 20-22 twisted self-associated templates, 18 organogels, 23 and helical metal nanostructures 24 as hosts and templates. Most of the reported systems, however, require the multi-step synthesis of host/template, the modification of guest substrate and/or the irradiation in organic media at low temperature. From the Sustainable Development Goals (SDGs) point of view, a readily accessible, spontaneously self-organisable, operative under ambient conditions, yet biodegradable host/template is advocated, while a three-dimensionally well-defined, appropriately functionalised, structurally robust host/template is essential for directing the stereochemical course of photoreaction to desired product(s). Upon photoirradiation in aqueous media, AC form antiand syn-isomeric head-to-tail (HT) cyclodimers (ACD1 and ACD 2) and head-to-head (HH) cyclodimers (ACD 3 and ACD 4) in a 4:1 ratio (Table 1, entry 1) for steric and electrostatic reasons. Possessing two functional groups on the same side of molecule, the HH cyclodimers are structurally attractive as building blocks for functional devices and materials. 25,26 Wolff et al. succeeded to increase the HH/HT ratio of the photo-cyclodimerisation of 9-substituted anthracenes by executing the reaction in cationic and anionic micelles to gain modestly enhanced HH/HT ratios of 0.62-0.76, 27,28 for which the flexible micelle shell would be responsible for the limited value of HH/HT ratios.

We synthesized N-benzoyl-protected peptide nucleic acid (PNA) monomers, which are robust under the conditions for deprotecting the 9-fluorenylmethoxycarbonyl (Fmoc) group by piperidine but are remo...

Intracellular delivery is crucial not only in achieving effective oligonucleotide therapeutics but also for a wide variety of therapeutic strategies. In this study to elucidate the effects of the number of incorporated arginine residues on cell membrane permeability, we designed a series of peptide ribonucleic acids (PRNAs) that alternatingly incorporated 4, 8, or 12 arginine residues (PRR1-3) in the PRNA backbone for experimental verifications. Indeed, the cellular uptake efficiency and the aggregation properties turned out to be critical functions of the number of incorporated arginine residues. Thus, the optimized PRR2 that incorporates 8 arginines showed the most efficient cellular uptake ability, much higher than that of octaarginine, without accompanying cytotoxicity or aggregation.

2016年４月14日夜および４月16日未明に熊本県で気象庁震度階級では最も大きい震度７を観測する地震が発生し、その後の約２週間で1,000回を超える余震が観測された。熊本市教育委員会は、日本臨床心理士会経由で都道府県臨床心理士会にスクールカウンセラー（以下、「SC」と略記）の緊急派遣を依頼し、三重県臨床心理士会からも５月23日から７月22日までの９週間、計７名のSCの緊急派遣を行った。本資料は、SC派遣をする側の三重県臨床心理士会としての支援体制を検証するため、派遣決定から終了までの経過をまとめることを目的としている。

Molecularly imprinted cavities have functioned as a regioselective reaction field for the [4 + 4] photocyclodimerization of 2-anthracenecarboxylic acid (2-AC). Molecularly imprinted polymers were prepared by precipitation polymerization of N-methacryloyl-4-aminobenzamidine as a functional monomer to form a complex with template 2-AC and ethylene glycol dimethacrylate as a crosslinking monomer. The 2-AC-imprinted cavities thus constructed preferentially bound 2-AC with an affinity greater than that toward structurally related 9-anthracenecarboxylic acid, 2-aminoanthracene, and unsubstituted anthracene. Moreover, from the four possible regioisomeric cyclodimers, they mediated the [4 + 4] photocyclodimerization of 2-AC specifically to the anti-head-to-tail (anti-HT) isomer. This indicates that the imprinted cavities accommodate two 2-AC molecules in an anti-HT manner, thereby facilitating the subsequent regioselective photocyclodimerization.

The UV-protective ability of mycosporine-like amino acids (MAAs) has been well documented and is believed to serve as a protecting agent for marine organisms from solar radiation. However, the effective UV absorption by MAAs has not been well correlated to MAA (neutral) structures. In this study, the origin of UV-protecting ability of MAAs was elucidated by experimental and theoretical spectroscopic investigations. The absorption maxima of mycosporine-glycine and shinorine in the UVA region were practically unaffected over a wide range of pH 4-10 and only slightly blue-shifted at pH 1-2. It was revealed that the zwitterionic nature of the amino acid residue facilitates the protonation to the chromophoric 3-aminocyclohexenone and 1-amino-3-iminocyclohexene moieties and the operation of the charge resonance in the protonated species well accounts for their allowed low-energy transitions in the UVA region. The RI-CC2/TZVP calculations on model systems in their protonated forms well reproduced the observed transition energies and oscillator strengths of MAAs, only with insignificant systematic overestimations of the both values. The slight hypsochromic shifts at pH 1-2 were explained by (partial) protonation to a carboxylate anion in the amino acid residue, as confirmed by theory. Fluorescence spectral investigations of shinorine were also performed for the first time in water to confirm the effective nonradiative deactivation. Consequently, this study unequivocally demonstrated that the 3-aminocyclohexenone as well as 1-amino-3-iminocyclohexene moieties, which are readily protonated at a wide range of pH, are responsible for the UV-protective ability of aqueous solution of MAAs.

Employing the module strategy based on our recent finding that the recognition behavior of peptide ribonucleic acid (PRNA) with complementary DNA/RNA is effectively controlled by the anti-to-syn or...

Chiral slipped 5,8:9',10'-cyclodimers were preferentially produced over classical 9,10:9',10'-cyclodimers upon supramolecular photocyclodimerization of 2-anthracenecarboxylate (AC) mediated by β-cyclodextrin (β-CD). This photochirogenic route to the slipped cyclodimers, exclusively head-to-tail (HT) and highly enantioselective, has long been overlooked in foregoing studies but is dominant in reality and is absolutely supramolecularly activated by 2:2 complexation of AC with β-CD. The intricate structural and photophysical aspects of this higher-order complexation-triggered process have been comprehensively elucidated, while the absolute configurations of the slipped cyclodimers have been unambiguously assigned by comparing the experimental and theoretical circular dichroism spectra. In the 2:2 complex, two ACs packed in a dual β-CD capsule are not fully overlapped with each other but are only partially stacked in a slipped anti- or syn-HT manner. Hence, they do not spontaneously cyclodimerize upon photoexcitation but instead emit long-lived excimer fluorescence at wavelengths slightly longer than the monomer fluorescence, indicating that the slipped excimer is neither extremely reactive nor completely relaxed in conformation and energy. Because of the slipped conformation of the AC pair in the soft capsule, the subsequent photocyclodimerization becomes manipulable by various internal or external factors, such as temperature, pressure, added salt, and host modification, enabling us to exclusively obtain the slipped cyclodimers with high regio- and enantioselectivities. In this supramolecularly driven photochirogenesis, the dual β-CD capsule functions as a chiral organophotocatalyst to trigger and accelerate the nonclassical photochirogenic route to slipped cyclodimers by preorganizing the conformation of the encapsulated AC pair, formally mimicking a catalytic antibody.

The synthesis and optical properties of 1,8-diphenyl-9,10-bis(arylethynyl)phenanthrenes, which are distorted phenanthrenes, are reported. The presence of the two phenyl groups at the 1,8-positions of phenanthrene significantly distorts the molecular geometries, as was evidenced by X-ray crystallography. The congested substitution pattern in the K region results in a distorted aromatic framework, which leads to a redshift in the emission spectrum. These observations are in stark contrast to 9,10-bis(phenylethynyl)phenanthrene with no phenyl groups at the 1,8-positions. A large Stokes shift suggested extensive structural relaxation between the phenyl and arylethynyl units in the excited state, which was supported by theoretical calculations.

A simple strategy for choosing optimal bio-supramolecular mediators from the mammalian serum albumin library is proposed for bimolecular photochirogenic reactions. Thus, the enantiodifferentiating photocyclodimerization of 2-anthracencecarboxylate (AC) was optimized in chemical and optical yields, when mediated by porcine and canine serum albumins, both of which bound two AC molecules in the first productive site to give the (P)-enantiomer of syn-head-to-tail-cyclodimer in 69% yield and 89% enantiomeric excess (ee) for the former but the (M)-enantiomer in 77% yield and 97% ee for the latter.

Competitive cross-/homo-photocyclodimerization of anthracene (AN) and 2-anthracenecarboxylic acid (AC) mediated by a chiral hydrogen-bonding template (TKS) was investigated under various conditions. The cross-photocyclodimerization was favored by a factor of 4-5 at all temperatures and wavelengths examined to afford the AC-AN cross-dimer in 80-84% yield even at AN/AC = 1 and in 98% yield at AN/AC = 10. The enantiomeric excesses (ee's) obtained were 27-47% for the homo-dimers and 21-24% for the cross-dimer. The absolute configuration of the cross-dimer was determined by comparing the experimental and theoretical circular dichroism spectra and further correlated with the re/si enantiotopic-face selectivity upon AC-TKS complexation in the ground state. Detailed analyses of the complexation behavior and the fluorescence lifetime and cyclodimerization rate of excited re/si complexes revealed that the product's ee is critically controlled not only by the relative abundance of the re/si complexes in the ground and excited states but also by their relative photocyclodimerization rate. Crucially, the ground-state thermodynamics and the excited-state kinetics are not synergistic but offsetting in enantiotopic-face selectivity, and the latter overwhelms the former to give the homo- and cross-dimers in modest ee's. Finally, some practical strategies for enhancing the enantioselectivity in chiral template-mediated photochirogenesis have been proposed.

An unprecedented 2:2 complex was shown to intervene in the enantiodifferentiating photocyclodimerization of 2-anthracenecarboxylic acid (A) mediated by a hydrogen-bonding template l-prolinol (P) to accelerate the formation of chiral anti-head-to-head and achiral syn-head-to-head cyclodimers in99% combined yield with enhanced enantioselectivities of up to 72% ee for the former. The supramolecular complexation and photochirogenic behaviors, as well as the plausible structures, of intervening Am·Pn complexes (m, n = 1 or 2) were elucidated by combined theoretical and experimental spectroscopic, photophysical, and photochemical studies. Furthermore, the photochemical chiral amplification was achieved for the first time by utilizing the preferential 2:2 complexation of A with homochiral P to give normalized product enantioselectivities higher than those of the template used. The present strategy based on the higher-order hydrogen-bonding motif, which is potentially applicable to a variety of carboxylic acids and β-aminoalcohols, is not only conceptually new and expandable to other (photo)chirogenic and sensing systems but also may serve as a versatile tool for achieving photochemical asymmetric amplification and constructing chiral functional supramolecular architectures.

The (P)- and (M)-3-azonia[6]helicenyl β-cyclodextrins exhibit L/D selectivities of up to 12.4 and P/M preferences of up to 28.2 upon complexation with underivatized proteinogenic amino acids in aqueous solution at pH 7.3.

Isophthalic and terephthalic acid monoesters of cyclic nigerosyl-(16)-nigerose (CNN), a cyclic tetrasaccharide composed of four d-glucopyranosyl residues connected by alternating α-1,3- and α-1,6-linkages, were synthesized as novel chiral supramolecular sensitizers for enantiodifferentiating photoisomerization of (Z)-cyclooctene (1Z) to planar chiral (E)-isomer (1E). Despite the saucer-shaped shallow cavity of CNN that does not immediately guarantee strong ground-state interactions with 1Z, the sensitizer-appended CNNs afforded optically active 1E in such enantiomeric excesses that are much improved than those obtained with an α-cyclodextrin analog and comparable with those obtained with a β-cyclodextrin analog. Interestingly, the enantiomeric excess values obtained were a critical function of temperature and solvent to show an inversion of the product chirality by changing the environmental variants. Nevertheless, all of the differential activation parameters calculated from the temperature-dependent enantiomeric excesses gave an excellent compensatory enthalpy–entropy relationship, indicating an operation of a single enantiodifferentiating mechanism in the present chiral photosensitization with modified CNNs. Chirality 24:921–927, 2012. © 2012 Wiley Periodicals, Inc.

What is important in student counseling is to understand the psychological theme of client. And the attitude of counselor toward the theme of his/her client is also important. For comprehending these theme more deeply, this paper is intended as an exploration into the work of comic, "Mushi-Shi", which is written by Urushibara Yuki. In this work, there are important images that are substantial for understanding the process of psychotherapy. Examples of these images are the ones of "initiation" and "wounded healer" and so on. Firstly, in this paper, the background of "Mushi-Shi" was mentioned. Secondly, Minakata Kumagusu who was a Japanese naturalist was introduced as the model of the main character, Ginko. And then, the process in which Ginko accepts "Mushi", which is grotesque and lively being, and create his attitude toward "Mushi" was discussed. On the story titled "Sugame-no-Uo (which means 'fish blind in one eye')", Yoki, who is the precursor of Ginko, was swallowed by Tokoyami, which is one of Mushi. Yoki was deprived his name and memory by Tokoyami, and called himself Ginko. In this process, there is an image of initiation. Afterwards, on the story titled "Kusa-no-Shitone (which means 'bed of grass')", young Ginko accepted his strange constitution and anguish. The motif of "wounded healer" is especially found in this story. For psychotherapy, it is substantial to comprehend these images. But the most substantial point is not to remain on this comprehension mentioned in this paper, but to go back to original work itself. We are able to experience more fertile image by going back there.

As the SC system spread, activities of clinical psychologists in school became outreach style and SC-Teacher collaboration is becoming an important issue. In this paper, we reconsider the "collaboration", which clarify the "roles" of teachers and SCs, and propose a new paradigm. In previous research (Takashima et al., 2007, 2008), both Japanese SCs and teachers had "SC-like" and "teacher-like" viewpoints, and inspite of their job type their individual "way of reviewing cases" ("perspective") existed as an internal framework. In this study, comparing the practice of Western (Swiss) SPs who function independently, it was discovered that Japanese SC relations are characterized by an "understanding of feelings." In order to create SC-Teacher collaborations, there is a need for a relational "multiple viewpoint mode" that takes advantage of Japanese mentality. This approach will have them reflect their own mind towards their "viewpoints" and "perspectives," rather than defining people and events through static, substantive "roles."

The enantiodifferentiating [4+4] photocyclodimerization of anthracenecarboxylic acid (AC) mediated by native, mono- and di-3,6-anhydro-γ-cyclodextrins was investigated in both aqueous solution and solid-state. The solid-state photolyses gave inherently disfavored head-to-head photodimers in much higher chemical and optical yields than in the aqueous solution.

Photophysics and photochemistry of 2-anthracenecarboxylate (AC) bound to bovine serum albumin (BSA) were investigated in detail for the first time by electronic absorption, circular dichroism (CD), steady-state and time-resolved fluorescence, fluorescence quenching, and product analysis studies. Through the spectroscopic investigations, it was revealed that the four independent binding pockets of BSA, which are known to accommodate 1, 3, 2, and 3 AC molecules in the order of decreasing affinity, are distinctly different in hydrophobicity, chiral environment, and accessibility. Interestingly, AC bound to site 1 gave highly structured fluorescence with dual lifetimes of 4.8 and 2.1 ns in an intensity ratio of 3:2, which may be assigned to the existence of two positional or orientational isomers within the very hydrophobic site 1. In contrast, the lifetime of AC in site 2 was much longer (13.3 ns), and ACs in sites 3 and 4 have broader fluorescence spectra with lifetimes that were practically indistinguishable from that in bulk water (15.8 ns). Although each of sites 2-4 simultaneously binds multiple AC molecules, no CD exciton coupling or static fluorescence quenching was detected, indicating that ACs bound to each site are not in close proximity to each other. Quenching studies with nitromethane further confirmed the significant difference in accessibility among the binding sites; thus, ACs bound to sites 1 and 2 are highly protected from the attack of the quencher, affording 32 and 10 times smaller rate constants than that for free AC in water. Product studies in the presence and absence of nitromethane more clearly revealed the photochirogenic performance of each binding site. Although the addition of nitromethane did not greatly alter the product distribution, the enantiomeric excesses (ee's) of chiral cycloadducts 2 and 3 were critically manipulated by selectively retarding the photoreaction occurring at the more accessible binding sites. Thus, the highest ee of 38% was obtained for 2 in the presence of 18 mM nitromethane, while the highest ee of 58% was attained for 3 in the absence of nitromethane, both at [AC]/[BSA]=3.6.

The absolute configuration has been established of the enantiopureanti-head-to-head cyclodimer of anthracene-2-carboxylic acid (AC) cocrystallized with L-propinol and dichloromethane [systematic name: (S)-2-(hydroxymethyl)pyrrolidin-1-ium (5R,6S,11R,12S)-8-carboxy-5,6,11,12-tetrahydro-5,12:6,11-bis([1,2]benzeno)dibenzo[a,e][8]annulene-2-carboxylate dichloromethane monosolvate], C5H12NO+·C30H19O4−·CH2Cl2. In the crystal structure, the AC dimer interacts with L-prolinol through a nine-membered hydrogen-bonded ring [R22(9)], while the dichloromethane molecule is incorporated to fill the void space. The absolute configuration determined in this study verifies a recent assignment made by comparing theoreticalversusexperimental circular dichroism spectra.

Y. Matsushita, H. Sekiguchi, C. Jae Wong, M. Nishijima, K. Ikezaki, D. Hamada, Y. Goto & Y. C. Sasaki "Nanoscale Dynamics of Protein Assembly Networks in Supersaturated Solutions", Scientific Reports, Volume 7, Article number: 13883, Springer Nature, 2017, Proteins in solution are conventionally considered macromolecules. Dynamic microscopic structures in supersaturated protein solutions have received increasing attention in the study of protein crystallisation and the formation of misfolded aggregates. Here, we present a method for observing rotational dynamic structures that can detect the interaction of nanoscale lysozyme protein networks via diffracted X-ray tracking (DXT). Our DXT analysis demonstrated that the rearrangement behaviours of lysozyme networks or clusters, which are driven by local density and concentration fluctuations, generate force fields on the femtonewton to attonewton (fN – aN) scale. This quantitative parameter was previously observed in our experiments on supersaturated inorganic solutions. This commonality provides a way to clarify the solution structures of a variety of supersaturated solutions as well as to control nucleation and crystallisation in supersaturated solutions.

In the supramolecular photocyclodimerization of 2-anthracenecarboxylate mediated by 6(A),6(D)-diguanidino-γ-cyclodextrin (CD), the chiral sense and enantiomeric excess of the photoproduct were dynamic functions of temperature and cosolvent to afford the (M)-anti head-to-head cyclodimer in 64% ee in aqueous methanol at -70 °C but the antipodal (P)-isomer in 86% ee in aqueous ammonia at -85 °C, while the corresponding diamino-γ-CD host did not show such unusual photochirogenic behaviors. The ee landscape was very steep against the temperature and sign-inverted against the ammonia content to reveal the opposite temperature dependence at low and high ammonia contents, for which an altered solvent structure and/or guanidinium-carboxylate interaction mode would be responsible.