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A rotaxane composed of a ring molecule having a metaphenylene unit, which swings as a pendulum, and a dianthrylethane unit, which undergoes isomerization in response to external stimuli, and an axle molecule with two different stopper units was synthesized. The rates of the rocking motion, which were switched reversibly, changed substantially by changing the size of the ring component in response to photo- and thermal-stimuli.

Environments significantly influence the sensation of pedestrians, while sensing and navigation technologies can help people improve their trip comfort. In this paper, we present an integrated framework, named NaviComf, which constructs pedestrian navigation systems to improve comfort in time varying environments taking into account the heterogeneous environmental factors. With NaviComf we aim to systematically provide solutions to the four key issues: (1) how to organize the huge amount of sensor data, (2) how to forecast future environmental information, (3) how to incorporate the heterogeneous environmental factors, and (4) how to select optimal paths in time varying environments. We have gathered sensor data of air temperature, relative humidity, and pedestrian congestion in real environments. We have also implemented a prototype system on the basis of the framework using the sensor data. Results of simulations and evaluations show that NaviComf can efficiently provide more comfortable paths as compared with the traditional navigation method.

A series of 3-(2-aminocarbonylphenyl)propanoic acid analogs possessing the (1R)-1-(3,5-dimethylphenyl)-3-methylbutylamine moiety on the carboxyamide side chain were synthesized and evaluated for their binding affinity for the EP1-4 receptors and their antagonist activity for the EP3 receptor. Rational drug design based on the structure of the metabolites in human liver microsomes led us to the discovery of another series of analogs. Several compounds were further evaluated for their in vivo efficacy in rats after oral administration and also for their pharmacokinetic profiles including in vitro stability in the liver microsomes.

To develop a synthetic method of thiophene-based polycyclic aromatic compounds, we investigated the tandem cyclization of 1,6-dithienyl-1,5-hexadien-3-ynes under flash vacuum pyrolysis (FVP) conditions at high temperatures (850 or 1050 °C). As a result, several isomeric naphthodithiophene derivatives were obtained as mixtures, from which a few isomers were isolated. The structural assignments of the products were performed on the basis of combination of the experimental and calculated 1 H NMR chemical shifts of either purified products or mixtures of them. Plausible mechanisms for the formation of the products are proposed.

A butadiyne-bridged square-shaped pyridinophane 2b having ester groups derived from triethylene glycol monomethyl ether was prepared and its self-assembling properties were investigated to assess the repulsive dipole–dipole interaction in less polar solvent and solvophobic driving force in polar solvents. Concentration-dependent 1H NMR spectra showed that whereas 2b did not self-assemble in chloroform-d, it did in polar solvents consisting of chloroform-d and methanol-d4 (4:6 to 6:4) with increasing association constants with the increasing methanol-d4 composition. Comparison of the free energies of association with those of the previously reported benzene macrocycle 1b indicates that solvophobically induced self-association of 2b is more promoted than 1b. The reasons for this difference are discussed from both enthalpy and entropy points of view.

Resonance Raman spectra of hydrogen-capped linear carbon molecules, polyynes H(–C C–)nH (n = 5,6), were measured in n-hexane. For C10H2, the peaks at 2123 cm−1 and 2017 cm−1 were identified as the ν3(σg) and ν4(σg) modes in D∞h symmetry, respectively. For C12H2, the peaks of ν3(σg) at 2097 cm−1 and ν4 (σg) at 2053 cm−1 were identified. The relative intensities of the first-order Stokes lines and their resonance enhancement are discussed in terms of the Franck–Condon overlap and resonance absorption relevant to the fully-allowed electronic transition of 1 Σ u + ↔ X ∼ 1 Σ g + .

In order to develop a chiral stationary phase (CSP), which has even higher separation ability than the corresponding commercially available crown ether based CSP (OA-8000 having a pseudo-18-crown-6 ether with an OMe group as a selector), chemically bonded type CSP having a phenolic OH group on a crown ring was developed. Normal mobile phases with or without acid additive can be used with this OH type CSP in contrast to the conventional OMe type CSP which has a neutral chiral selector. Enantiomers of 25 out of 27 amino compounds, including 20 amino acids, 5 amino alcohols, and 2 lipophilic amines, were efficiently separated on a column with this CSP. Nine amino compounds out of 27 were separated with better separation factors than the corresponding OMe type CSP. It is noteworthy that the chromatography on this CSP exhibited excellent enantiomer-separations for amines and amino alcohols when triethyl amine was used as an additive in the mobile phase. Comparison of enantiomer separation ability on this OH type of CSP and on the OMe type of CSP and correlation between the enantioselectivity in chiral chromatography and that of the corresponding model compounds in solution imply that the chiral separation arose from chiral recognition in host guest interactions.

Phenolic pseudo-24-crown-8 ( S , S )- 3 , pseudo-27-crown-9 ( S , S )- 4 , and podands ( R , R )- 5 and ( R , R )- 6 possessing phenyl groups as chiral barriers were prepared and their chiral recognition properties toward secondary neutral amines were examined. Pseudo-24-crown-8 ( S , S )- 3 and podand ( R , R )- 5 showed sufficient binding ability and moderate chiral recognition ability toward secondary amines.

Chiral crown ether (S,S)-3 having a pseudo-24-crown-8 ring and chiral podand (R,R)-4 were prepared and both exhibited good chiral recognition ability toward secondary amines, N-α-dimethylbenzylamine (15) and propranolol (16).

Flash vacuum pyrolysis of 1,6-diphenyl-1,5-hexadien-3-yne at 1000°C and its bromo derivative at 800°C yielded chrysene as the major product through tandem diaryldienyne cyclizations.

Butadiyne-bridged [4 4 ]- and [4 8 ]metacyclophanes having exo -annular t -butyl groups were prepared by intermolecular Eglinton coupling of the dimeric unit or by intramolecular ring closure of the linear tetramer. Comparison of the 1 H and 13 C NMR spectra of [4 4 ]metacyclophane with those of [4 8 ]cyclophane and diphenylbutadiyne revealed its prominent geometrical feature due to deformation of the triple bonds from linearity. The [4 4 ]Metacyclophane was converted into [0 8 ]thiophenometacyclophane in good yield by treatment with sodium sulfide.

[16.16.16](1,3,5)Cyclophanes fused by six [4.3.2]propellatriene units, which would serve as precursors to cage polyyne C60H6 and its perchloro derivative C60Cl6, respectively, were prepared. In the negative mode laser desorption mass spectra of the cyclophanes, the polyyne anions C60H6− and C60Cl6− were detected. Moreover, size-selective formation of C60+ as well as C60− was also observed, indicating the possible polyyne cyclization mechanism to form the fullerene cage.

The enantioselectivity of the kinetic resolution of a primary alcohol which has a chiral center at the β-position of the hydroxyl group was substantially improved by employing a racemic mixture of a chiral acyl donor for enantioselective transesterification catalyzed by a lipase. The combination of the lipase, solvent, and acyl donor was also effective for the enantioselectivity. In addition, the important effect of the chirality of an acyl donor on kinetic resolution was investigated by using enantiomerically pure acyl donors. Here we demonstrate the effective kinetic resolution ( E =98) of a primary alcohol, 2-phenyl-1-propanol, by using a racemic mixture of a chiral acyl donor, vinyl 3-phenylbutanoate.

A series of rotaxanes 1 · 5 , 2 · 5 , 3 · 5 , and 4 · 5 bearing a different substituent (X = NO 2 , Br, H, and OMe, respectively) at para position on the phenol moiety of the ring component exhibit clear difference in deslipping behavior. The difference in the deslipping rates is consistent with the difference in intercomponent hydrogen bonding strength estimated from the O–H stretching vibration wavenumbers. The para substituent dictates the relative strength of the intra- and intermolecular hydrogen bonds. Thus the incorporation of an intramolecular hydrogen bond allows for tunability of the strength of the intercomponent interaction.

Homochiral crown ether ( S , S )- 1 containing 1-naphthyl groups as chiral barriers together with the phenol moiety was prepared by using ( S )- 3 as a chiral subunit which was resolved in enantiomerically pure form by lipase-catalyzed enantioselective acylation of (±)- 3 . Homochiral phenolic crown ether ( S , S )- 2 , containing phenyl groups as chiral barriers, was also prepared from ( S )- 5 which was derived from ( S )-mandelic acid. The association constants for their complexes with chiral amines in CHCl 3 were determined at various temperatures by the UV–visible spectroscopic method demonstrating that the crown ethers ( S , S )- 1 and ( S , S )- 2 displayed the large Δ R − S Δ G values of 6.2 and 6.4 kJ mol −1 , respectively, towards the amine 21 at 15°C. Thermodynamic parameters for complex formation were also determined and a linear correlation between T Δ R − S Δ S and Δ R − S Δ H values was observed.

Crown ether (S,R,R,S)- 1 containing chiral subunits derived from (1R,2S)-cis-1,2,3,4-tetrahydronaphthalene-1,2-diol and the phenol moiety bearing the intra-annular OH group and the 2,4-dinitrophenylazo group at its para-position have been prepared in enantiomerically pure form. The association constants for the complexes with chiral amines have been determined at various temperatures by the UV-visible spectroscopic method and thermodynamic parameters of complex formation have been calculated.

m-Xylylene type dithioureas self-assemble to form an orthogonal dimer structure both in solution and solid state, wherein the four thiourea groups constitute a cyclic array of the closed network of the hydrogen bond through head-to-tail binding mode. This novel dimer structure was elucidated on the basis of 1H NMR spectra, vapor pressure osmometry, and X-ray crystal structure analysis.

Crown ethers 1–6 containing two chiral subunits derived from ( S )-1-phenylethane-1,2-diol and a phenol moiety bearing an intra-annular OH group and an additional para -substituent have been prepared in enantiomerically pure forms and their enantiomer recognition behaviour in complexation with neutral amines has been examined by the 1 H n.m.r. spectroscopic method.

Enantiomerically pure azophenolic crown ethers 1–4 containing ( S )- or ( R )-1-phenylethane-1,2-diol moieties and (2 S ,4 S )-2,4-dimethyl-3-oxapentane-1,5-diol moiety as a chiral subunit were prepared; crown ethers (S,S,S,S)- 1 showed high chiral recognition behaviour in complexation with 2-substituted 2-aminoethanol derivatives.

We synthesized diethynylbenzene macrocycles (DBMs), cyclic oligomers of diethynylbenzene, having functional groups in the periphery of the macrocyclic framework and investigated their self-association properties in solution resulting from π-π stacking interaction. The tetrakis-DBM having hexadecyl ester groups showed dimerization behavior not only in chloroform-d, but also in o-dichlorobenzene-d4.

Lipase QL (from Alcaligenes sp.)-catalyzed acylation of alcohols using isopropenyl acetate as the acylating agent in diisopropyl ether converted preferentially primary alcohols with an S configuration and secondary alcohols with an R configuration into the corresponding homochiral acetates. On the basis of observed enantiomer selectivities, a predictive active site model for lipase QL is proposed for identifying which enantiomer of a primary or a secondary alcohol reacts faster in this acylation.

Lipase QL-catalyzed acylation of secondary alcohols using isopropenyl acetate as the acylating agent in diisopropyl ether gave preferentially the corresponding acetate with an R configuration. On the basis of the results, a predictive active site model for lipase QL is proposed for identifying which enantiomer of a secondary alcohol reacts faster in this reaction.

The design and synthesis of chiral crown ethers possessing a chiral recognition ability which carry great potential for separation of enantiomers and analytical purpose has become an important and rapidly growing field of host-guest chemistry. One of the advantages of crown ethers constructed using a synthetic chiral building block is that it is rather easy to modify the chiral cavity resulting in the improvement in enantiomer selectivity. Cyclohexane-1,2-diol derivatives such as cis -1-phenylcyclohexane-1,2-diol, trans -1-phenylcyclohexane-1,2-diol and trans - 1,2-diphenylcyclohexane-1,2-diol are of interest as chiral building blocks of crown ethers, because incorporation of these subunits into the 18-crown-6 framework causes a reduction in conformational flexibility of the chiral cavity and fixes the phenyl chiral barrier perpendicularly above the face of crown ring to modify enantiomer recognition ability. Chiral crown ethers of the 18-crown-6 type were synthesized using these building blocks and their chiral recognition behaviour in differential enantiomer transport through bulk liquid membranes were examined. Chiral azophenolic crown ethers containing cis -1-phenylcyclohexane-1,2-diol or cis -cyclohexane-1,2-diol which can bind neutral amines to form a stable complex and exhibit enantiorecognitive coloration in complexation with chiral amines were prepared and the association constants for their complexes with chiral ethylamine and ethanolamine derivatives were determined on the basis of UV-visible absorbance. The observed enantioselectivity is rationalized in terms of complementarity between a host and a guest as indicated by CPK molecular model examination. The alternation of the position of chiral barriers resulted in a reversal of the enantioselectivity. Crown ethers with diastereotopic faces can bind a guest to each side of the diastereotopic faces to form diastereoisomeric complexes which occasionally cause troublesome “sidedness” problems. In order to avoid the problems, most crown ethers previously prepared contained at least one C 2 axis of symmetry. However, diastereotopic face selectivity in complexation does provide helpful information on the complexing behaviour of crown ethers to assist in the design of more elaborate and structured host molecules. meso -Crown ethers having cis-1-phenylcyclohexane-1,2-diol were prepared and the diastereotopic face selectivity by their diastereotopic faces in complexation with achiral amines was examined by temperature-dependent 1H nuclear magnetic resonance. Ethanolamine is attached stereoselectively to one of the faces to give one of diastereoisomeric complexes and the alternation of the position of steric barriers led to reversal of the diastereotopic face selectivity. A prediction of which diastereoisomeric complex is formed is made on the basis of CPK molecular model.

Primary alcohols having a hydroxymethyl group at an S stereogemic center and secondary alcohols with an R configuration are preferentially acylated to give the corresponding acetates by lipase YS (from Pseudomonas fluorescens )-catalyzed acylation using isopropenyl acetate as the acylating agent in diisopropyl ether. On the basis of enantiomer selectivities observed, a predictive active site model for lipase YS is proposed for identifying which enantiomer of a primary or a secondary alcohol reacts faster in this acylation.

Homochiral azophenolic crown ethers 1 and 2 having three chiral barriers, that is, the phenyl group, the methyl group, and the cyclohexane moiety on each of the homotopic faces have been prepared. The enantiomer recognition toward chiral 2-aminoethanol derivatives has been examined.

[6](1,4)Naphthalenophane ( 1a ), [6](1,4)anthraceniophane ( 2a ), and the perisubstituted derivatives 1b , 1c , and 2b were prepared by the benzoannelation method. The conformational behavior of 1b, 1c , and 2b suggests that their bridged aromatic rings are more distorted than those of the parent systems 1a and 2a .

Novel chiral stationary phases consisting of silica gel covalently bound with chiral pseudo-18-crown-6 type hosts, which possess either an OH or OMe group as a binding functionality, were prepared for enantiomer-separation of lipophilic amines.

Homochiral 1-(1-adamantyl)ethane-1,2-diol ( 5 ) was prepared and its absolute configuration was determined to be ( S )-(+)- 5 by enzymatic and 1 H n.m.r. spectroscopic methods. Using ( S )-(+)- 5 as a chiral subunit, the homochiral crown ether (+)- 18 was synthesized and its enantioselectivity in complexation of methionine methyl ester perchlorate was also examined by the 1 H n.m.r. spectroscopic method.

Pig liver esterase, lipase from porcine pancreas, lipase from Pseudomonas sp. (lipase YS), and lipase from Candida cylindracea catalyzed hydrolyses of the cis-diacetate 1 and the trans-diacetate (±)-4 to give the cis-monoacetate 3 and the trans-monoacetate 6 in optically active forms, respectively. Lipase YS-catalyzed acylations of the cis-diol 2 and the trans-diol (±)-5 with an acylating agent in cyclohexane yielded (−)-3 and (−)-6, respectively. The group adjacent to the R stereogenic center preferentially reacted in lipase YS-catalyzed hydrolyses of 1 and (±)-4 and acylations of 2 and (±)-5, and the enantioselectivities are rationalized by our rule recently proposed for lipase YS.

[6](1,4)Naphthalenophane ( 1 ) and [6](1,4)anthracenophane ( 2 ) underwent thermal cycloaddition with tetracyanoethylene to give the corresponding [2+2] adducts 3 and 4 . Anthracenophane 2 reacted with dimethyl acetylenedicarboxylate to yield the 1:1 and 1:2 adducts 6 and 7 .

An article written in Japanese in 1979 recorded the reexamination of the Pasteur's experiment on spontaneous resolution and many useful sketches of the hemihedral crystals of sodium ammonium tartrate.

Metalation of [6]paracyclophane ( 1 ) with a superbase generated metalocyclophanes 2a and 3a regioselectively which led to mono substituted derivatives 2b – 2e and para disubstituted 3b , 3d , and 3e .

The novel synthesis of descarboxyquadrone (3) and its model compound (4) by using the acid-catalyzed rearrangement of [4.3.2]propellanones is described.

The Baeyer-Villiger oxidation of exo -7-acetyl[4.2.1]- and exo -7-acetyl[4.2.2]propellanes (2X) and (3X) mainly proceeds via unusual carboration intermediates to afford the rearranged products.

The synthesis, structure and reactivities of [6]paracycophanes 2a-c, the smallest bridged [n]paracydophanes so far isolated, are described. The parent hydrocarbon 2a has been efficiently synthesized by oxidative decarboxylation of [6.2-2]propellenecarboxylic acid (7) by lead tetraacetate. The 8-carbomethoxy derivative 2b has been quantitatively synthesized by thermal valence isomerization of the [6.2.2]propelladiene (4b) (Dewar isomer of 2b). X-Ray structure analysis of the crystalline 2c has revealed that the benzene ring of 2c severely deformed into a boat conformation with deformation angles of α= 20.5° and β = 18.5°. Furthermore, the bond angles of the bridging chain (C(2), C(3), C(4) and C(5)) are considerably expanded from the normal sp3 angle. Vaporphase thermolysis of 2a gives the spiro triene 12 via homolysis at the benzyl position. Add-catalyzed isomerization of 2a with trifluoroacetic add takes place readily to afford the meta and ortho isomers 13a and 14a in a ratio of 1:3. UV irradiation of the ester 2b brings about valence isomerization to the Dewar isomer 4b which isomerizes slowly to the prismane derivative 15a on further irradiation. A [4+2] cycloaddition of 2a with N-phenyl-l,2,4-triazoline-3,5-dione occurs at room temperature to give mainly adduct 16. Addition of bromine to 2a takes place to furnish quantitatively the unstable 1,4-addition product 18. Oxidation of 2a with mCPBA readily takes place to give the dienone dimer 20 which affords on UV irradiation the cage diketone 21 derived from intramolecular photocycloaddition.

Bicyclo[6.2.2]dodecadienes (2), (3a), and (3b) having two bridgehead double bonds were synthesized by the pyrolysis of the acetate (1).

A novel cyclophane host, 2, 11, 20-trihydroxy-2,5,8,11,14,17,20,23,26-nonamethyl [3.3.3]paracyclophane ( 4 ), has been synthesized and found to form complexes with polar organic guest molecules by hydrogen bonding.

cis,trans-Tricyclo[6.3.0.01,4]undecan-5-one (2) rearranged under acidic conditions through unusual pathways to give cis,cis-tricyclo[6.3.0.01,5]undecan-4-one (3). The application to the α-methylene derivative of 2 afforded the angularly fused triquinane having an α-methylenecyclopentanone unit.

Reaction of (Z)-[6]paracycloph-3-ene (1) with tetracyanoethylene gave [2+2] cycloadduct 4 and that with trifluoroacetic acid in methanol afforded 1,4-adduct 8.

Tricyclic ketones 3a, b and 7a–c having angularly fused 5-6-5 or 5-7-5 ring system have been efficiently prepared by irradiation of bicyclic enones 1 and 2.

The photoreaction of 2-naphthols 1a-e with ethylene in the presence of aluminum halide gave the [2+2] cycloadducts 3a-e in good yields.

Condensation of 8,9:17,18-didecalino-4,13-diaza-18-crown-6 with 1,8-diiodo-4,5-decalino-3,6-dioxaoctane in the presence of sodium carbonate produced proton cryptate, tridecalino[2.2.2]cryptand⊃2HI.

The acid-catalyzed rearrangement of the 1-oxaspirohexane derivatives 2a,b,d gave the corresponding functionalized norcaranes 3a,b,d in moderate to good yields.

Oxidative decarboxylation of [n.2.2]propellane carboxylic acids ( 1a - c ) with lead tetraacetate gave the bicyclic acetates ( 2b , c ) having a bridgehead double bond and/or the tricyclic acetates ( 3a , b ) in good yields. Vapor phase thermolysis of 3a or 3b afforded the bridgehead olefin 2a or 2b quantatively.