Motohiro Shizuma

Osaka Research Institute of Industrial Science and Technology

Interlocked compounds such as rotaxanes and catenanes exhibit unique kinetic properties in response to external chemical or physical stimuli and are therefore expected to be applied to molecular machines and molecular sensors. To develop a novel rotaxane for this application, an isophthalamide macrocycle and a neutral phenanthroline axle were used....

To obtain chiral luminescent nematic liquid crystals (N*‐LCs), two sets of chiral perylene luminescent materials (R,R)/(S,S)‐N,N′‐bis(1‐cyclohexylethyl)perylene‐3,4,9,10‐tetracarboxylic diimide [(R,R)/(S,S)‐CPDI] and (R,R)/(S,S)‐N,N′‐bis(1‐phenylethyl)perylene‐3,4,9,10‐tetracarboxylic diimide [(R,R)/(S,S)‐BPP] were prepared and doped into a nematic...

Pseudogluconobacter saccharoketogenes produces glucaric acid from d-glucose via two pathways, i.e., through d-glucuronic acid or d-gluconic acid. These pathways are catalyzed by alcohol dehydrogenase, aldehyde dehydrogenase, and gluconate dehydrogenase. Although d-glucaraldehyde and l-guluronic acid are also theorized to be produced in pathways thr...

A novel synthesis of degenerate [2]rotaxanes with two different amine stations is presented. Variable‐temperature ¹H NMR and rotating‐frame nuclear Overhauser effect correlation spectroscopy experiments revealed that the addition of trifluoroacetic acid initiates molecular shuttling. The activation barrier for the motion remained constant even when...

The capabilities and performance of γ-titanium phosphate (γ-TiP) with 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) as a latent thermal catalyst were investigated by the copolymerization of glycidyl phenyl ether (GPE) and hexahydro-4-methylphthalic anhydride (MHHPA) at different temperatures for a period of one hour. Polymerization was not observed unti...

It is important to optimize the photoexcited-state conformation of chiral luminescent molecules to enhance the intensity of circularly polarized luminescence (CPL) and control the direction of CPL rotation. In pyrenyl peptide luminophores, the intensity and sign of CPL is determined by the solvent and intramolecular distance between pyrenyl units i...

Racemic 1-phenylethanols were converted into enantiopure (R)-1-phenylethanols via a chemoenzymatic process in which manganese oxide driven oxidation was coupled with enzymatic biotransformation by compartmentalization of the reactions, although the two reactions conducted under mixed conditions are not compatible due to enzyme deactivation by Mn io...

A water-soluble coumarin monomer comprising quaternary ammonium ionic moiety can bind with a γ-cyclodextrin (γ-CD) macrocyclic host in a 2:1 ratio to form a homoternary complex in water. The coumarin...

An electrospray ionization mass spectrometric method for the simultaneous analysis of the enantiomeric excess of free amino acids, without chromatographic separation, was demonstrated using a quasi-racemic mixture of deuterium-labelled and unlabelled chiral copper(II) complexes. This convenient method enables the simultaneous high-sensitivity deter...

In the paper, the circularly polarised luminescence (CPL) properties of chiral perylene diimide (BPP) luminophores are described. Chiral BPP and its derivatives bearing substituents at the bay positions exhibited intense aggregation-induced enhanced CPL (AIEnh-CPL) in the PMMA-film state. Their AIEnh-CPL signs could be attributed to the effects of...

In 2004, the US Department of Energy listed D-glucaric acid as one of the top 12 bio-based chemicals and a potential biopolymer building block. In this study, we show that Pseudogluconobacter saccharoketogenes strains can produce D-glucaric acid from D-glucose, although in low yield because of the generation of the byproduct 2-keto-D-gluconic acid...

Three types of chiral perylene diimide luminophores bearing ethynyl, phenyl, and ethynylphenyl substituents (BPP‐Ethy, BPP‐Ph, and BPP‐EthyPh) at the bay positions were prepared. The chiroptical properties of the compounds in their solution (in CHCl3) and polymethyl methacrylate (PMMA)‐film solid states were investigated. Similar to the chiral BPP...

Yoshitane Imai et al. Sign dependence of MCPL spectra on type and position of substituent groups of pyrene and phenanthrene derivatives

Achiral pyrene and phenanthrene derivatives with electron-donating hydroxyl/methoxy and electron-withdrawing carboxylic acid groups exhibited magnetic circularly polarised luminescence at 360–410 nm in dilute solution under N-up and S-up Faraday geometries at 1.6 T.

A series of copper(II) complexes with chiral tetradentate ligands, N,N′-ethylene- bis(S-amino acid methyl amide or methyl ester) prepared from S-alanine, S-phenylalanine, S-valine or S-proline, was generated in methanol. The copper complexes provided three component complexes in the presence of a free chiral amino acid. The enantioselectivity for t...

Yoshitane Imai et al. Excimer-origin CPL vs. monomer-origin magnetic CPL in photo-excited chiral binaphthyl-ester-pyrenes: critical role of ester direction

Aiming toward the production and characterization of delicious and functional gel foods, this communication studies the flavor release from cinnamon-containing κ-carrageenan gel. Cinnamaldehyde, which provides the flavor of cinnamon, was released in a trace amount from the gel and detected by flame ionization detector gas chromatography. The retent...

Two chiral binaphthyl (BNp) derivatives bearing oppositely oriented ester linkers to two pyrene (Py) moieties [( R )/( S )- 1 and ( R )/( S )- 2 )] enabled Py-origin circularly polarized luminescence (CPL), magnetic CPL (MCPL), and circular dichroism...

The circularly polarized luminescence (CPL) signs of Eu(III) luminophores coordinated to axially chiral binaphthyl derivatives carrying acetic acid residues [(R,R,R)-4] were inverted compared to those bearing compounds (R)-1–3 by inserting bulky naphthalene units into the binaphthyl backbone. The suitable steric difference between the phenyl group...

Two types of planar chiral [2,2]paracyclophane-pyrene luminophores (1 and 2) with different binding positions of the fluorescent pyrene units were synthesised. (R)/(S)-1 with 1-pyrene units exhibited green intermolecular excimer circularly polarised luminescence (CPL) at 530 nm in the KBr-pellet, but exhibited no CPL signal in dilute CHCl3 solution...

The CPL sign is controllable by varying the number of naphthalene units and peptide/Eu( iii ) coordination ratio.

Enantioselective coordination of a free amino acid as the second ligand of a Cu( ii ) complex with a novel chiral tetradentate ligand was evaluated quantitatively in a short measurement time by ESI-MS/deuterium-labelled quasienantiomers.

By using electrospray ionization mass spectrometry coupled with the use of deuterium-labelled quasienantiomers, enantioselective coordination of a free amino acid as the second ligand of a copper(II) complex with a novel chiral tetradentate ligand was evaluated quantitatively in a short measurement time

Planar-chiral Phanephos, containing the coordinatable P(III), formed P(III)/Tb(III)(hfa)3 hybrid luminophores that successfully emitted characteristic circularly polarised luminescence (CPL) due to 5 D 4 → 7 F 5 transitions in solution. On the other hand, BINAP, containing...

The cover picture shows C2‐symmetrical structures with pyrene as a fluorescent unit that shows a characteristic non‐classical circularly polarised luminescence (CPL) control system. Simple molecular systems are composed of axially chiral binaphthyl, fluorescent pyrene, and linker units. These systems can control the sign of CPL signal according to...

The sign, wavelength, and intensity of circularly polarised luminescence, generated from two photoexcited pyrene moieties, were successfully controlled by selecting a suitable achiral wired structure to connect two achiral fluorescent pyrenes with an axially chiral binaphthyl backbone. Especially, these circularly polarised luminescence and circula...

The intercalation compound of benzimidazole with α-zirconium phosphate (α-ZrP) was evaluated as a latent thermal initiator in the reaction of glycidyl phenyl ether (GPE) and hexahydro-4-methylphthalic anhydride (MHHPA). No reaction occurred at 60 °C after 1 h. Upon increasing the temperature to 140 °C, the conversion reached 97% after 1 h. The dein...

Isomer analysis such as epimer identification of saccharides is one of the important subjects in mass spectrometry. Since isomers have the same mass, they cannot be distinguished by simple mass spectrometry only. Generally, the collision induced decomposition method is used for isomer analysis. A saccharide and a cation form a complex ion within se...

The cover picture shows a new cryptochiral system. Newly designed and synthesised axially chiral pyrene‐based luminophore exhibits cryptochiral circularly polarised luminescence (CPL). By controlling chirality through the use of light, the CPL properties of the luminophore can be exhibited, from very weak circular dichroism (CD) in the ground state...

The cover picture shows a new cryptochiral system. Newly designed and synthesised axially chiral pyrene-based luminophore exhibits cryptochiral circularly polarised luminescence (CPL). By controlling chirality through the use of light, the CPL properties of the luminophore can be exhibited, from very weak circular dichroism (CD) in the ground state...

Optically active luminophores capable of emitting circularly polarized light (CPL) are keys in many photonic communication systems. Herein, we report a new cryptochiral CPL‐functioned molecular system composed of a C2‐symmetric 5,5’,6,6’,7,7’,8,8’‐octahydro‐1,1’‐bi‐2‐naphthyl rotamer bearing two flexible linkers attached to two pyrene rings as emit...

Upon combining chiral peptides (the most basic chiral source) with pyrene moieties, we found that chiral oligopeptides bearing two-pendant pyrenyl units exhibited circularly polarised luminescence (CPL) originating from intramolecular excimers at 480–490 nm in various solvents, and the sign of their CPL signals depended on the type of solvent emplo...

Luminophores are key components in several optoelectronic applications and the development of methods for the synthesis of novel highly efficient luminophores is an important objective. Herein, new linear and hyperbranched polythiophenes bearing BINOL moieties through alkylene spacers were prepared by the electrochemical oxidation of the correspond...

The introduction of aromatic substituents onto the binaphth-yl backbone of axially chiral binaphthyl organic fluorophores shifts their circularly polarized luminescence (CPL) wavelengths to higher values and may induce CPL sign inversion. Herein, we succeeded in increasing the CPL wavelength without inverting the CPL sign by introducing an alkenyl...

Chiroptical signs in circularly polarised luminescence (CPL) of Eu(III) luminophores coordinated to C2-symmetric binaphthyl ring carrying carboxylic acids, (R)-1 (and (S)-1)) and (R)-2 (and (S)-2)) were inverted by inserting two oxymethylene spacers between the ring and the acids. The subtle difference in reorganization between (R)-1 and (R)-2 caus...

C2-symmetric binaphthyl derivatives are atropisomers. However, their dihedral angles in the photoexcited and ground states often alter in response to external and internal chemical influences. The cover picture shows that, when (R)-binaphthyl ring bearing carboxylic acids with/without two flexible oxymethylene spacers are chosen as ligands, chiropt...

The cover picture shows the sign control of circularly polarized luminescence (CPL) of enantiopure oligopeptides bearing two pyrenyl groups and methylene spacer reversed by changing solvent. Chiroptical signs in the photoexcited state (ES) and the ground state (GS) of chiral luminophores in solutions are not predictable because differences in the s...

The photoexcited and ground state chiralities of enantiopure oligopeptides bearing two pyrenyl groups (DD-2/LL-2: four methylene spacer between two pyrenyl groups and DD-1/LL-1: no methylene spacer thereof) in eight common organic solvents (CHCl3, CH2Cl2, MeOH, CH3CN, DMF, NMP, DMAc, and acetone) were investigated by means of circularly polarized l...

Showcasing research from the laboratories of Dr Yoshitane Imai at Kindai University, Japan and Dr Michiya Fujiki at Nara Institute of Science and Technology, Japan. Complexes of Eu(III)(hfa)3 with a planar chiral P(III) ligand (Phanephos): solvent-sensitive sign inversion of circularly polarised luminescence. By solely mixing chiral organophosph...

Complexes of Eu(iii)(hfa)3 with a C2-symmetric planar P(iii) ligand exhibited intense circularly polarised luminescence (CPL) due to (5)D0 ? (7)F1 and (5)D0 ? (7)F2 transitions, with the signs and shapes of CPL signals depending on the choice of solvent (acetone or chloroform).

The coordination of Eu(III) (from Eu(III)(hfa)3) by chiral P(III) (from BINAP) led to circularly polarised luminescence in dilute solutions on the order of |gem| = 10^-2 at 5D0 / 7F1 and |gem| = 1010^-3 at 5D0 / 7F2 transitions regardless of the coordinating ability of the solvent (i.e., in non-coordinating ethanol-free chloroform and coordinating...

The naphthoquinone pigment 2-methyl-3-(4- or 2-methylphenylthio)-1,4-naphthalenedione exhibits characteristic optical properties in both the solution and solid states. In the solid state, the position of the methyl (Me) group in the pigment imparts a range of characteristic colours. In the solution state, the 2-Me-substituted pigment exhibits solva...

Background: Emulsions stabilized by colloidal particles are known as Pickering emulsions. To date, soft microgel particles as well as inorganic and organic particles have been utilized as Pickering emulsifiers. Although cyclodextrin (CD) works as an attractive emulsion stabilizer through the formation of a CD-oil complex at the oil-water interface...

Reaction of t-butylcalix[8]arene (BCA[8]) as an A8-type monomer with hexamethylenediisocyanate as a B2-type monomer was examined to afford only soluble polymers in high yields. Analysis by 1H NMR, IR, MALDI-TOF mass spectroscopy, and AFM indicated that synthesized polymers consist of nanoscale-gel-shaped structures that contain fixed holes and cavi...

Unlike in the solution state, the first circularly polarized luminescence (CPL) property of the axially chiral binaphthyl fluorophore bearing two fluorescent terthiophene units was successfully observed by a chirality transfer from axially chiral binaphthyl to the terthiophenes, followed by amplified CPL signals in the solid state.

Cigarette smoke, a collection of many toxic chemicals, contributes to the pathogenesis of smoking-related diseases such as chronic obstructive pulmonary disease and cancer. Much work has been done on the chemical analysis of ingredients in cigarette smoke, but there are few reports on the active ingredients that can modify biomolecules. We used a s...

Arachidonyl alcohol rarely occurs in natural oils. It can be used as a substrate for production of several ether lipids possessing beneficial functions. Although arachidonyl alcohol has been produced on a laboratory scale by the chemical reduction of arachidonic acid, it will be difficult to scale up this process for industrial application. The aim...

We studied the mixing behavior of binary mixtures of alkylglycosides (CnGly); i.e. n-Octyl β-D-glucopyranoside, n-Decyl β-D-glucopyranoside and n-Decyl β-D-maltoside in combination with sodium laurate (NaL), and N,N-dimethyldodecylamine oxide in combination with NaL. The critical micelle concentration (CMC) data were obtained as functions of the co...

Review: 63 refs.

Poly(butyl methacrylate) and polystyrene were synthesized by emulsion polymerization using chemocleavable anionic surfactants (1a and 2a) derived from 1-O-alkylglycerols in order to resolve the problem that it is generally difficult to isolate the desired product from persistent emulsions. It has been previously determined that 1a decomposes comple...

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Novel double-chain nonionic surfactants with an acid decomposition function were prepared by acid-catalyzed condensation of chloroacetone with fatty alcohols (octyl, decyl, and dodecyl), followed by a Williamson reaction with polyethylene glycol without any expensive reagents and special equipment. These surfactants showed easy micelle formation co...

The heterochirality of a 1:2 metal/Ph-pybox complex ion was encyclopedically evaluated by ESIMS using pseudo-racemic (R,R)- and (S,S)-Ph-pybox pair, which were unlabeled/labeled by deuterium atoms, respectively. The heterochiral complex was predominantly formed in all investigated 1:2 metal/Ph-pybox complex ions.

Chiral discrimination by novel chiral hosts 3 and 4, which consist of an oxyethylene chain and 2,3:5,6-di-O-cyclohexylidene-β-D-mannofuranose moieties at both ends, was examined considering several protonated amino acid isopropyl ester guests using fast atom bombardment mass spectrometry (FABMS) with the enantiomer deuterium-labeled guest method. H...

Inclusions of alkali metal ions by permethylated inulin (MeInu) were examined by electrospray ionization (ESI) mass spectrometry and multinuclear nuclear magnetic resonance (NMR) spectroscopy. Complexes of MeInu with metal ions were observed as multicharged ions in ESI mass spectra. The number of fructofuranose units of MeInu binding to one metal i...

A simultaneous estimation of the chiral discrimination abilities of several chiral hosts was demonstrated on the basis of one mass spectrum. The chiral host mixture, including H(1), H(2), H(3) ..., and H(m) (m: number of hosts) was prepared by etherification of several chiral alcohols with bistosylate of diethylene glycol. An equimolar mixture of a...

The novel cyclic oligosaccharide, permethylated tetrasaccharide (CTS), determinates the enantiomers of chiral amino acid isopropyl ester hydrochlorides.

The chiral-discriminating abilities of new triazole-linked host compounds (6, 7) toward amino acid esters were evaluated by the FABMS/EL-guest method. Two types of host appending saccharide derivatives were synthesized by the copper-catalyzed Huisgen-1,3-dipolar cycloaddition (CuAAC). Host compounds binding constants and chiral-discriminating abili...

Two diastereomeric complex ions of a chiral material (enantiopure) with an equivalent mixture of a deuterium labeled one enantiomer and an unlabeled another enantiomer are observed in a mass spectrum, and the chiral discrimination ability or enantiopurity of the chiral materials are evaluated quantitatively on the basis of the relative peak intensi...

Polymerization processes of 4´-hydroxyphenyl α-glucoside (α-Arb) and 4´-hydroxyphenyl β-glucoside (arbutin, β-Arb) catalyzed by horseradish peroxidase (HRP) were analyzed in detail. A calculated model based on the coupling of the free radicals formed from the substrates with every degree of polymerization reproduced successfully most of the experim...

Oxidative polymerization of phenolic glucosides catalyzed by horseradish peroxidase (HRP) was reviewed. Hydroquinone β-glucoside (arbutin, β-Arb) and hydroquinone α-glucoside (α-Arb) were polymerized similarly responding to the addition of H2O2. A calculated model reproduced successfully most of the experimental results: An increase of the polymer...

4'-Hydroxyphenyl alpha-glucoside and 4'-hydroxyphenyl beta-glucoside were polymerized with horseradish peroxidase. The isolated dimers were found to have linkages at C3' of the hydroxyphenyl moieties and proved to be fluorescent. Low accumulation of oligomers was attributed to increasing electrochemical reactivity with polymerization degrees, which...

Horseradish peroxidase catalyzed an oxidative coupling reaction of 4′-hydroxyphenyl β-glucoside (arbutin) and 2,5-dihydroxybenzoic acid sodium salt (gentisate) using H2O2 as an electron acceptor to yield a precipitating yellow compound. An approximate arbutin/gentisate ratio of 1:2 was effective for the synthesis. The addition of 100–300 mM H2O2 to...

In the hydrogen ion titration of micelles, the degree of ionization of the micelle at a given pH has to be evaluated to obtain a pKa value of micelles (Ka being the proton dissociation constant) at the pH. We compared the degree of ionization obtained from 13C and 1H NMR spectra with that obtained from the stoichiometric method. We used dodecyldime...

The relative thermodynamic parameters, ΔΔG° enan(R/S), ΔΔH°enan(R/S), and ΔΔS°enan(R/S), on the enantioselective host-guest complexation equilibria were estimated easily using the temperature-dependent FAB mass spectrometry coupled with the enantiomer labeled guest method.

Polyaromatic compounds that carry several side residues of d-glucose, d-galactose, and d-mannose were synthesized from hydroquinone β-glucoside (arbutin) through two successive enzymatic reactions: glycosylation of the glucose residue in arbutin, followed by oxidative polymerization of the hydroquinone moieties. In the first step, Bacillus macerans...

Mogroside V (MV), a main sweet triterpene glycoside in the extract of the fruit of Luo-han-guo (Siraitia grosvenori Swingle), was transglycosylated by cyclodextrin glucanotransferases (CGTases) using starch as a donor substrate. CGTases from Bacillus macerans, B. circulans, B. stearothermophilus and Thermoanaerobacter sp. were effective for the tra...

We have investigated the mixing behavior of binary mixtures of the alkylglucosides (CnG) octyl beta-D-glucoside and decyl D-glucoside in combination with sodium oleate (NaOl), and the amine oxide surfactants (AO) N,N-dimethyldodecylamine oxide, N,N-bis (2-hydroxyethyl)dodecylamine oxide, and 3-lauramidopropyl-N,N-dimethylamine oxide in combination...

Chiral recognition in the host-guest complexation systems of chiral crown ether hosts and amino ester guests was thoroughly examined using the electrospray ionization (ESI) mass spectrometry/enantiomer labeled (EL)-guest method. In this method, the mass spectra of a mixture of three components in a solution, a chiral host (H), an equal amount of an...

The enantiomeric excess (e.e.) determination of organic amines and dipeptides has been examined using ESI and FAB mass spectrometry. Here, an equimolar amount of labeled and unlabeled enantiomeric host pair compounds is mixed with a given e.e.-unknown guest compound. This is called the enantiomer labeled (EL)-host method. The enantiomeric host pair...

Chiral recognition of carboxylic acids has been achieved using a “host-metal-guest complexation system” by the ESIMS/EL-guest method. The system consists of a nitrogen-containing acyclic host, La(NO3)3, and carboxylic acids. Chiral recognition in the system is evaluated by the IRIS value, which is defined by the relative peak intensities of the cor...

A new class of the aggregation of the gold(l) phosphine complex with pentafluorobenzenethiol ate ligand through intermolecular quadrupole interactions was designed and characterized both by X-ray crystallography in solid state and by electrospray ionization mass spectroscopy in solution.

New linear host (1) and cyclic hosts (2 and 3), which have galactopyranose skeletons as chiral origins and oxyethylenes skeletons as binding sites, were designed based on the structural features extracted from the fructo-oligosaccharide derivatives, having a large chiral discrimination ability, and were then synthesized. These hosts showed chiral d...

New chiral linear hosts (1–3, a: peracetylated derivatives, b: permethylated derivatives) containing monosaccharide end groups were designed on the basis of the structural features of permethylated 1F-fructonystose (MeFruNys), which shows a remarkable chiral discrimination ability, and then synthesized. The chiral discrimination ability of their ho...

The FAB mass spectrometry (MS)/enantiomer labeled (EL) guest method is one of the useful technique to easily evaluate chiral discrimination ability of a chiral host (H) toward chiral guests (GR⁺, GS-dn⁺). In this paper, the matrix dependency of the relative peak intensity (IRIS) of the diastereomeric host-guest complex ions [(H+GR)⁺ and (H+GS-dn)⁺]...

The chiral discrimination abilities of several variously permethylated carbohydrates toward various amino acid 2-propyl esters were combinatorially evaluated from the relative peak intensity of the 1:1 diastereomeric complex ions with the deuterium-labeled L-amino acid 2-propyl ester protonated ion and with the unlabeled D-amino acid 2-propyl ester...

The host–guest complexation behavior of cyclic oligosaccharides, permethylated cycloinulohexaose 1, permethylated cycloinuloheptaose 2, and permethylated cycloinulooctaose 3 with metal cations has been characterized by means of UV-visible, NMR, and electrospray ionization (ESI) mass spectrometry. In the crystal state, the structures of 1·K+, 1·Rb+,...

From a single fast atom bombardment mass spectrum, the optical purity (enantiomeric excess: ee) of chiral organic primary and secondary amine salts (guests) such as tryptophan 2-propyl ester hydrochloride and proline 2-propyl ester hydrochloride was easily determined with a high accuracy using both the deuterium-labeled/unlabeled enantiomeric host...

The chiral discrimination ability of permethylated glucopyrano-oligosaccharides toward amino acid 2-propyl ester hydrochlorides was evaluated using FAB mass spectrometry. In the given permethylated homo-oligosaccharides, permethylated β-cello-oligosaccharide series (II) showed remarkably higher S-selectivity toward tryptophan ester salts (Trp-O-iPr...

Among linear permethylated fructo-oligosaccharides containing various monosaccharide moieties at the reducing terminal, MeSorFru3, MeGlc6Fru3, and MeFruNys showed high degrees of enantioselectivity toward binding some amino acid 2-propyl ester salts. In particular MeFruNys indicated remarkable chiral discrimination toward [ValOPri]+ (IR/IS-Dn = 0.1...

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Optical purity (enantiomeric excess: eel of organic amine salts such as 1-(1-naphthyl)ethylamine hydrochloride was determined by FAB mass spectrometry using a deuterium-labeled/unlabeled enantiomer pair of a newly synthesized saccharide derivative (DD-Gal2deg/LL-Gal2deg-d(24)), podands.

Beta-fructofuranosidase fructosylated not only the hydroxyl group but also the thiol group of 2-mercaptoethanol in a transfer reaction using sucrose as a donor substrate. The enzymes from Candida utilis and Saccharomyces cerevisiae (bakers' yeast) were effective catalysts for the thio-fructofuranosylation. The thio-fructosylation product was isolat...

beta-Galactosidase catalyzed beta-galactosylation not only of a hydroxyl group but also of a thiol group in the condensation reaction of D-galactose and 2-mercaptoethanol. The thio-galactosylation product was confirmed as 2-hydroxyethyl S-beta-D-galactoside on the bases of fast atom bombardment mass spectrometry, infrared spectroscopy, and nuclear...

beta-Galactosidase catalyzed beta-galactosylation not only of a hydroxyl group but also of a thiol group in the condensation reaction of D-galactose and 2-mercaptoethanol. The thio-galactosylation product was confirmed as 2-hydroxyethyl S-beta-D-galactoside on the bases of fast atom bombardment mass spectrometry, infrared spectroscopy, and nuclear...

Chiral recognition of the host-guest complexations between the (RRRR)-18-crown-6-tetracarboxylic acid (18 C6TCA) host (H) and α-amino acid or their ester derivative guests (G) has been systematically determined using both FAB mass spectrometry (MS) and capillary zone electrophoresis (CE). A comparison of these two techniques for the same series of...