bluuebunny/crossref_metadata_2025_split huggingface dataset:
Time-resolved Near Infrared Surface-enhanced Raman Scattering Spectroscopy of a Surface-confined Electrochemical Reaction
Authors: Ishioka Toshio , Uchida Tatsuya , Teramae Norio 
Published: September 2003

Abstract
A time-resolved surface-enhanced Raman scattering (SERS) system was developed using a step-scan near-infrared Fourier transform(FT) spectrometer. The developed system with a submillisecond time resolution was applied to a surface-confined reaction of totally two-electron redox of 9,10-phenanthrenequinone(PQ). From the electrochemical and spectroscopic results, the standard electrochemical rate constant was calculated to be 0.08 s−1 for PQ adsorbed on a Au electrode.
LiCl Catalyzed Knoevenagel Condensation: Comparative Study of Conventional method vs Microwave Irradiation
Authors: Sabitha Gowravaram , Reddy B V Subba , Babu R Satheesh , Yadav J S 
Published: September 2003

Abstract
LiCl catalyzes the condensation of aromatic aldehydes with active methylene compounds either in NMP or DMF at room temperature or under microwave irradiation in dry media to produce olefinic products in high yields.
Circular Dichroism Spectrophotometric Determination of Metal Ions by Using Optically Resolved Sparingly Soluble fac(S)-[Rh(aet)3](aet = 2-Aminoethanethiolate)
Authors: Aizawa Sen-ichi , Sone Yasushi , Yamada Shin-kichi , Nakamura Motoshi 
Published: September 2003

Abstract
Sparingly soluble neutral fac(S)-[Rh(aet)3] (aet = 2-aminoethanethiolate) was optically resolved completely. The S-bridged complex formation of the optically active isomer of fac(S)-[Rh(aet)3] was utilized for the selective determination of metal ions by using circular dichroism spectra.
Ferromagnetic Chain Complex of Ruthenium(II, III) Pivalate with Pyridyl Nitronyl Nitroxide
Authors: Sayama Yasuyoshi , Handa Makoto , Mikuriya Masahiro , Hiromitsu Ichiro , Kasuga Kuninobu 
Published: September 2003

Abstract
A chain complex of ruthenium(II, III) dimer with pyridyl nitronyl nitroxide, [Ru2(O2CCMe3)4(p-pynit)]n(BF4)n(p-pynit = 2-(4-pyridyl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazolyl-1-oxyl 3-oxide) has been prepared and charactarized by the X-ray crystal structure analysis. The magnetic susceptibility data show that a ferromagnetic interaction is operative between the ruthenium(II, III) dimers and pyridyl nitronyl nitroxides.
Reversible Oxygenation of a μ-Acetato-di(μ-phenoxo)dicobalt(II) Core Complex and Crystal Structure of Its Oxygenated Complex
Authors: Furutachi Hideki , Fujinami Shuhei , Suzuki Masatatsu , Okawa Hisashi 
Published: September 2003

Abstract
A μ-acetato-di(μ-phenoxo)dicobalt(II) core complex of the dinucleating macrocycle, derived from the [2:1:1] condensation of 2,6-diformyl-4-methylphenol, ethylenediamine and diethylenetriamine, forms a μ-peroxo complex whose structure is determined by X-ray crystallography.
Selective Detection of D-Lactulose by a Porphyrin-based Diboronic Acid
Authors: Kijima Hideomi , Takeuchi Masayuki , Shinkai Seiji 
Published: September 2003

Abstract
Cis-5,15-bis[2-(dihydroxyboronyl)phenyl]-10,20-diphenylporphine (cis-DBPP) bearing two boronic acid groups in a 9 Å distance has been synthesized. The absorption, fluorescence, and CD spectral changes were induced only by D-lactulose among 10 disaccharides tested herein. One can readily sense D-lactulose by the spectroscopic methods.
An Electroreflectance Study at the Bottom-Surface of a Mercury Drop Electrode Placed on an Underlying Nafion Film
Authors: Sagara Takamasa , Hiasa Hideo , Nakashima Naotoshi 
Published: September 2003

Abstract
Electroreflectance measurement at the bottom-surface of a mercury drop electrode on an underlying Nafion film on a cell bottom has been demonstrated for the redox reaction of heptylviologen in an aqueous solution.
Manganese(II) Chloride-Catalyzed Alkylmagnesation of 2-Alkynylphenol
Authors: Nishimae Shinji , Inoue Rie , Shinokubo Hiroshi , Oshima Koichiro 
Published: September 2003

Abstract
Treatment of 2-alkynylphenol with an alkyl Grignard reagent in the presence of a catalytic amount of manganese(II) chloride provided 2-(2-alkyl-1-alkenyl)phenol in good yield. Alkylmagnesation proceeded with high regio- and stereoselectivities.
Addition of Acrylamide to Amino Aldehydes to Generate Non-Baylis-Hillman Adducts. Formation of Novel N-Acylhemiaminals
Authors: Bussolari Jacqueline C , Beers Kimberly , Lalan Praful , Murray William V , Gauthier Diane , McDonnell Patricia 
Published: September 2003

Abstract
Aldol reactions of chiral aminoaldehydes and methylacrylate in the presence of 1,4-diazabicyclo[2.2.2]octane (DABCO) produces β-hydroxy methylbutenoates which can be utilized as psuedodipeptides. However, reaction of aminoaldehydes with acrylamide in the presence of DABCO afforded the adducts derived from the addition of the acrylamide nitrogen to the aldehyde to generate N-acylhemiaminals. These reactions were found to proceed at a faster rate than the typical Baylis-Hillman reaction and also require the presence of DABCO.
Z-Isomers of Azobenzenes Highly Compatible with Liquid Crystals
Authors: Ruslim Christian , Ichimura Kunihiro 
Published: September 2003

Abstract
Novel guest-host liquid crystal systems containing 3,3-disubstituted azobenzenes as guests were prepared on the basis of molecular design by molecular calculations to achieve the improvement of compatibility of the chromophore with nematic phases. No phase change of nematic liquid crystals was induced by the E-to-Z photoisomerization of the guests even at doped concentrations as high as 20 wt%.
Asymmetric Anionic Polymerization of N-Substituted Maleimides with Et2Zn and Chiral Bisoxazolines
Authors: Onimura Kenjiro , Tsutsumi Hiromori , Oishi Tsutomu 
Published: September 2003

Abstract
Anionic polymerizations of N-substituted maleimides (RMI:R=cyclohexyl (CHMI), R=phenyl (PhMI)) were achieved by chiral anionic initiator such as diethylzinc (Et2Zn)–chiral bisoxazoline (R′box) to afford optically active poly(RMI). The polymerizability was enhanced by the accelerated nucleophilicity of the ethyl groups in Et2Zn due to R′box ligands. The specific rotations of poly(PhMI) ([α]25435 −28.4 to + 94.6°) were much improved than those initiated by n- BuLi - R′box.
Thermally Stable Aluminas for High Temperature Applications
Authors: Giannos Mary , Hoang Manh , Turney Terry W 
Published: September 2003

Abstract
Thermal decomposition of the ammonium analogue of the mineral dawsonite, NH4Al(OH)2CO3·H2O, yields high surface area γ-alumina. The surface area can remain as high as 145 m2/g after calcination at 1000 °C. NH4Al(OH)2CO3·H2O can also be used as precursor for alumina-based binary or mixed oxides. Treatment of NH4Al(OH)2CO3·H2O with appropriate amounts of Ba(OH)2 and La(NO3)3 led to the formation of layered aluminate structure on subsequent heating. Highly thermally stable materials with surface areas of up to 25 m2/g after sintering at 1400 °C were obtained.
A Novel Class of Organogelator Based on N-Isopropylcholamide and the First Observation of Fibrous Colloidal Aggregates
Authors: Hishikawa Yukio , Sada Kazuki , Watanabe Ryousuke , Miyata Mikiji , Hanabusa Kenji 
Published: September 2003

Abstract
N-Isopropylcholamide afforded three kinds of matters in organic solvents; organogels, inclusion crystals, and guest-free crystals. The gelation occurred in aromatic liquids in the presence of methanol as a good solvent, while the inclusion crystals were formed when adding ethanol, 1-propanol, or acetone as a good solvent. The guest-free crystals were obtained in benzene when using 2-butanone, 2-pentanone, or 3-pentanone. Electron microscopic image of the organogel exhibited that the network was formed by gathering of many colloidal particles of several hundreds nanometers in diameter.
Catalytic Reaction of Model Zinc(II) Complex for Active Sites of Mono-nuclaer Zinc-peptidases
Authors: Ogawa Kazuya , Nakata Kou , Ichikawa Kazuhiko 
Published: September 2003

Abstract
Catalytic hydrolysis reaction of amide by designed zinc-complex model for active sites of mono-nuclear zinc-peptidases has been investigated. The effect of carboxylate ligand of the model complex on hydrolysis activity was revealed by kinetic analyses.
Investigation of the Diastereoselectivity During the Addition of an Enantiomerically Pure (2-Lithiophenyl)acetaldehyde Acetal to Various Imines
Authors: Wünsch Bernhard , Nerdinger Sven 
Published: September 2003

Abstract
The diastereoselectivity during the addition of the homochiral (2-lithiophenyl)acetaldehyde acetal 1b to various imine components was investigated. The diastereoselectivity could be raised to 84.2% de by addition of 1b to benzylidenanisidine 2h. Removal of the tosyl and the p-methoxyphenyl protective groups of 3c, 4c and 3h/4h succeeded with sodium in liquid ammonia and ammonium cerium(IV) nitrate, respectively, to yield the enantiopure benzhydrylamines 5 and 6.
Red Organic Electroluminescent Devices Based on Novel Furan-Contained Eu Complex as an Emitting Layer
Authors: Okada Keizou , Uekawa Masahiro , Wang Yan-Feng , Chen Tian-Ming , Nakaya Tadao 
Published: September 2003

Abstract
A novel europium complex, Eu(DFP)3(phen)(DFP=1,3-Di-(2-furyl)-1,3-propanedione, phen=1,10-phenanthroline), was synthesized and used as an emitting material in organic eletroluminescent (EL) devices. The structure of fabricated EL devices is composed of ITO/TPD/Eu(DFP)3(phen)/AlLi(99:1). The double layered EL device emitted red light originating from Eu(DFP)3(phen) with a maximum luminance of 34.3 cd/m2 at 12 V and 25.7 mA/cm2.
Enantiospecific Formation of a Three-component Helical Structure by Spontaneous Self-assembly
Authors: Yue Weimin , Bishop Roger , Scudder Marcia L , Craig Donald C 
Published: September 2003

Abstract
A toluene solution of the two racemic helical tubulands 1 and 2 yields crystals of the stoichiometric product 1·22·toluene through molecular self-assembly involving simultaneous self-resolution of both diols. This composite helical tubulate structure contains parallel tubes with cross-sectional areas of 22.5 Å2.
Synthesis of Fullerene-Porphyrin Complex
Authors: Maruyama Hiroyuki , Fujiwara Masahiro , Tanaka Kazuyoshi 
Published: September 2003

Abstract
C60-porphyrin complex (1) has been synthesized for the first time. In this complex, two functional molecules are linked by a direct metal-C60 bond. Characterization of 1 is performed with a 1H and 13C NMR and an electrospray ionization mass-spectroscopy (ESI-MS). The UV/Vis spectrum of 1 in benzene showed the strong absorption positioned at 280 and 326 nm assigned to the electronic transitions in C60 moiety, which were red-shifted by 3 nm and blue-shifted by 7 nm with respect to those of pristine C60, respectively. A new absorption band at λmax=780 nm appeared in a longer-wavelength region. This band was assigned to metal-to-ligand charge transfer (MLCT) transition from ruthenium to fullerene.
Synergy of CoAl2O4 and Al2O3 in CoAl2O4-Al2O3 Catalysts for Selective Reduction of Nitrogen Monoxide with Ethene in Excess Oxygen
Authors: Okazaki Noriyasu , Yamamoto Yoshitaka , Itoh Hidenobu , Tada Akio 
Published: September 2003

Abstract
A well-mixed CoAl2O4-Al2O3 catalyst calcined at 800 °C showed higher activity for the title reaction than that calcined at 500 °C as well as a roughly-mixed CoAl2O4-Al2O3 catalyst. The results of characterization suggested that in a CoAl2O4-Al2O3 catalyst the synergy of CoAl2O4 and Al2O3 particles at their interfaces is a critical factor causing its high activity.
Micro-rings of Manganese Dioxide Nanocrystals on Mica
Authors: Yamamoto Sadaaki , Matsuoka Osamu , Sugiyama Shoko 
Published: September 2003

Abstract
Circularly ordered self-assembly (micro-ring) of manganese dioxide nanocrystals were formed simply by dewetting a manganese dioxide colloidal aqueous solution on mica. The balance between the repulsive force of the nanocrystals and the compressive force of shrinking droplets plays an important role in forming this peculiar nanosize assembly.
Synthesis and Reactions of the First Stable 1-Germaallene
Authors: Tokitoh Norihiro , Kishikawa Kuniyuki , Okazaki Renji 
Published: September 2003

Abstract
The first stable 1-germaallene was synthesized by treatment of an extremely hindered alkylidenetelluragermirane with a large excess amount of hexamethylphosphorous triamide or by reductive dechlorination of the corresponding overcrowded (1-chlorovinyl)chlorogermane with t-butyllithium in THF. The germaallene was isolated as a colorless solid by the latter synthetic method and found to be fairly stable even in solution at room temperature, although it underwent an intramolecular cyclization at 80 °C in benzene.
Synthesis of Borosilicate Zeolites by Dry Gel Conversion (DGC) Method
Authors: Bandyopadhyay Rajib , Kubota Yoshihiro , Sugi Yoshihiro 
Published: September 2003

Abstract
Synthesis of borosilicate zeolites, namely [B]-BEA, [B]-MFI and [B]-MTW by dry gel conversion (DGC) method was described for the first time. Phase selection and thereby the outcome of the product was dependent upon the gel composition, mainly on the SiO2/B2O3 ratio and the TEAOH content.
A New 2,2′-Bipyridinium Salt with Pink Electrochromism for the Modification of Nanocrystalline TiO2-Electrodes
Authors: Boehlen Raetus , Felderhoff Michael , Michalek Ralf , Walder Lorenz 
Published: September 2003

Abstract
A nanocrystalline TiO2 thin film electrode on conductive glass was modified with a new 2,2′-bipyridinium salt. Deep pink electrochromism of moderate stability was observed.
Facile and Selective Alkylation of 3,3,3-Trifluoropropene Oxide (TFPO) with Organoaluminum Reagents via Pentacoordinate Trialkylaluminum Complexes
Authors: Ooi Takashi , Furuya Mayumi , Maruoka Keiji 
Published: September 2003

Abstract
A new organoaluminum-promoted selective alkylation of 3,3,3-trifluoropropene oxide (TFPO) with several nucleophiles has been developed which involves the chelation-activated addition to fluoro epoxides via pentacoordinate trialkylaluminum complexes.
New Family Member of Hydrogen Molybdenum Bronze, HxMoO3
Authors: Eda Kazuo , Sukejima Ai , Matsuura Naomi , Sotani Noriyuki 
Published: September 2003

Abstract
We found out a new family member of hydrogen molybdenum bronze, HxMoO3. The phase exhibited the monoclinic system and appeared as a single phase in the region of 0.45 &gt; x &gt; 0.25. Its interlayer spacing varied largely depending on the hydrogen content.
Protein Assembly on Solid Surfaces by Gel-Assisted Transfer (GAT) Technique
Authors: Kimizuka Nobuo , Fujikawa Shigenori , Kunitake Toyoki 
Published: September 2003

Abstract
Water soluble proteins –ferritin and hemoglobin– were spread on the surface of agarose gel, and transferred to solid substrates via contact with solid substrates. Formation of monolayer and multimeric layers of proteins was confirmed by electron microscopy and UV-Vis spectroscopy.
Trioxane Derivative as an Acid Amplifier Exhibiting a Non-linear Organic Reaction
Authors: Arimitsu Koji , Ichimura Kunihiro 
Published: September 2003

Abstract
2,4,6-Tris[2-(p-toluenesulfonyloxy)ethyl]-1,3,5-trioxane was prepared to be subjected to the acid-catalyzed decomposition to release three p-toluenesulfonic acid molecules which were able to act as an acid amplifier to enhance the photosensitivity of a chemically amplified photoresist.
Electrochemical Reduction of CO2 in Micropores
Authors: Yamamoto Toshio , Hirota Kouske , Tryk Donald A , Hashimoto Kazuhito , Fujishima Akira , Okawa Masafumi 
Published: September 2003

Abstract
CO2 electroreduction was examined on high area nickel electrocatalysts supported on activated carbon fibers, which contain slit-shaped pores with widths on the order of nanometers. The current efficiency for CO2 reduction to CO reached values of 70%. In contrast, much smaller amounts of CO were generated for the same type of high area nickel catalyst supported on non-activated carbon fibers. The enhancement of the CO2 reduction selectivity with the microporous support is thought to include a nanospace effect, which gives rise to high pressure-like effects at ambient pressure.
Photoasymmetric Synthesis of [Co(edta)]− from Co(II) Salt and L4edta (L=H+ or Na+), Using a Chiral Cu(I) Complex
Authors: Sakaki Shigeyoshi , Horita Rikihisa , Kuraki Koichi , Hamada Taisuke 
Published: September 2003

Abstract
[Co(edta)]− was photochemically synthesized from CoX2 (X=NO3− or OAc−) and L4edta (L=H+ or Na+) with a chiral Cu(I) complex, under irradiation of near UV light (350–370 nm). Λ–[Co(edta)]− was produced in excess (7% e.e.) from Co(OAc)2 and H4edta, while Δ–[Co(edta)]− was produced in excess (7% e.e.) from Co(OAc)2 and Na4edta. When Co(NO3)2 was used, Λ–[Co(edta)]− was yielded from either H4edta or Na4edta.
New Aspect of Methanesulfonyl Chloride: Unusual Deoxygenations of Pyridine N-Oxides with methanesulfonyl Chloride and Triethylamine
Authors: Morimoto Yoshiki , Kurihara Hajime , Yokoe Chiho , Kinoshita Takamasa 
Published: September 2003

Abstract
Treatment of several pyridine N-oxides with an excess of methanesulfonyl chloride and triethylamine brought about a deoxygenation reaction to give efficiently the corresponding reduction products without chlorination of the pyridine nucleus.
Determination of Relative and Absolute Stereochemistry of Cephalosporolide D and Its Enantioselective Total Synthesis
Authors: Shiina Isamu , Fukuda Yoshio , Ishii Toshihiro , Fujisawa Hidehiko , Mukaiyama Teruaki 
Published: September 2003

Abstract
An efficient method for the synthesis of (−)-cephalosporolide D was established via successive enantioselective aldol reaction and effective construction of 8-membered ring lactone moiety.
Calix[4]arene Derivative Bearing π-Coordinate Substituents as Neutral Carrier for Silver Ion Sensors
Authors: Kimura Keiichi , Tatsumi Kenta , Yajima Setsuko , Miyake Saori , Sakamoto Hidefumi , Yokoyama Masaaki 
Published: September 2003

Abstract
Calix[4]arene tetra(allyl ether) 1 was applied as a neutral carrier of silver ion sensors, which exhibited an excellent silver ion selectivity against sodium ion, while calix[4]arene tetra(allyl ester) 2 possesses only poor silver ion selectivity with severe sodium ion interference.
Synthesis and Anion Binding Ability of Metacyclophane-Based Cyclic Thioureas
Authors: Tobe Yoshito , Sasaki Shin-ichi , Mizuno Masaaki , Naemura Koichiro 
Published: September 2003

Abstract
Cyclophanes having two thiourea groups were synthesized and their anion binding ability was examined by titration method using 1H-NMR spectroscopy. Strong and selective anion binding of the preorganized cyclic receptors was observed in the general order of H2PO4− &gt; CH3COO− &gt; Cl− &gt; HSO4− &gt; Br−.
Epoxidation of Olefins with H2O2 Catalyzed by an Electronegatively-Substituted Iron Porphyrin Complex in Aprotic Solvent
Authors: Lee Yoon Jung , Goh Yeong Mee , Han So-Yeop , Kim Cheal , Nam Wonwoo 
Published: September 2003

Abstract
Catalytic epoxidation of olefins by hydrogen peroxide in the presence of an electronegatively-substituted iron porphyrin complex yielded epoxide products in acetonitrile solution. An iron(III) hydroperoxide porphyrin complex was proposed as a reactive intermediate responsible for the olefin epoxidations.
Compressibility and Volume Changes of Lysozyme due to Inhibitor Binding
Authors: Gekko Kunihiko , Yamagami Keigo 
Published: September 2003

Abstract
The adiabatic compressibility and partial specific volume of hen egg-white lysozyme, which were determined by the sound velocity and density measurements at 25 °C, decreased by addition of its inhibitors, N-acetyl-D-glucosamine oligomers, in the order of monomer &gt; dimer &gt; trimer. This result demonstrates that the inhibitor binding induces the atomic packing in the cleft of the active site to diminish the structural fluctuation of the protein.
Oxygen Reduction Characteristics on Pyrolytic Graphite Electrodes Modified with Electro-polymerized Salen Compounds
Authors: Okada Tatsuhiro , Katou Kihoko , Hirose Takuji , Yuasa Makoto , Sekine Isao 
Published: September 2003

Abstract
Electro-polymerized cobalt salen compounds on pyrolytic graphite electrodes were first tested as oxygen reduction catalysts in aqueous solutions of various pH. From electrochemical measurements it was revealed that although in acidic media the catalyst performance deteriorated, the performance in neutral and basic media was relatively good as compared to that of platinum, the best catalyst for this reaction.
Mechanism and Potential Energy Surface for Photoisomerization of Stilbene in Zeolite Nanospace
Authors: Kuriyama Yasunao , Takeya Haruhiko , Oishi Shigero , Kojima Masanobu 
Published: September 2003

Abstract
The photoisomerization of cis- and trans-stilbenes adsorbed in zeolite supercage was studied by means of Raman spectroscopy for in situ analysis of the isomer ratio in the photostationary state. It was found that the isomerization proceeds mainly through the singlet excited states for NaY and triplet excited states for KY, and also a new potential energy surface for the photoisomerization was proposed.
4,4′-(Trimethylene)bis(2,6-di-t-butylphenoxy) Diradical: An Application of the Sequential Redox-Solid State Photolysis (SRSSP) Method
Authors: Nakatuji Koji , Oda Masaji , Kozaki Masatoshi , Morimoto Yoshiki , Okada Keiji 
Published: September 2003

Abstract
The oxidation of 4,4′-(trimethylene)bis(2,6-di-t-butylphenol) with lead dioxide underwent intramolecular cyclization at the 4,4′-positions to give a dispiro-compound. Irradiation of the dispiro-compound in a methylcyclohexane matrix at −150 °C produced 4,4′-(trimethylene)bis(2,6-di-t-butylphenoxy) diradical which has a stable triplet state.
Helical Stereoregular Artificial Glycoconjugate Polymers Based on Poly(phenylacetylene) Backbone: Synthesis and Molecular Recognition with Lectin
Authors: Matsuura Kazunori , Furuno Shin-ichi , Kobayashi Kazukiyo 
Published: September 2003

Abstract
Stereoregular poly(phenylacetylene)s bearing pendant lactose and cellobiose moiety were synthesized by polymerization of β-N-glycosylated 4-ethynylbenzamides with [Rh(nbd)Cl]2 (nbd=norbornadiene) as initiator. The glycoconjugate polymer possessed alternating double bond backbone with cis-transoidal regioregularity and helical conformation. Inhibition assay of hemagglutination revealed that galactose-specific lectin efficiently bound to the stereoregular helical glycopolymer bearing lactose, but the binding was not so strong as that of the corresponding flexible glycoconjugate polystyrene.
In Situ Infrared Spectroscopic Studies of Adsorption of Lactic Acid and Related Compounds on the TiO2 and CdS Semiconductor Photocatalyst Surfaces from Aqueous Solutions
Authors: Awatani Tadashi , Dobson Kevin D , McQuillan A James , Ohtani Bunsho , Uosaki Kohei 
Published: September 2003

Abstract
In situ attenuated total reflectance infrared (ATR-IR) spectroscopy has been used to determine the structure of adsorbed lactic acid (LA) compounds on the surfaces of titanium dioxide (TiO2) and cadmium sulfide (CdS) photocatalysts. LA was found to chelate onto the TiO2 in a b identate fashion, while in the CdS case, LA was adsorbed electrostatically as the lactate ion. These differing surface interactions are likely to determine the selectivity in the photo-products of LA.
Optically Active Tetrapyrazinoporphyrazines and Their Circular Dichroism in Monomeric and Dimeric Forms
Authors: Kobayashi Nagao , Nevin W Andrew 
Published: September 2003

Abstract
Metal-free and copper derivatives of tetrapyrazinoporphyrazines containing four (1R)-(−)- or (1S)-(+)-camphor units have been synthesized and their circular dichroism (CD) has been studied: in monomeric state, R and S isomers showed mainly positive and negative CD signs, respectively, while CD pattern in a cofacial dimeric state suggested that R and S isomers stack in left- and right-handed helix, respectively.