bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Synthesis of Some Dimethylpyranocoumarins and Isopropenyldihydrofuranocoumarins
Authors: Yamaguchi Seiji , Miyakawa Ryozo , Yonezawa Shinobu , Kawase Yoshiyuki 
Published: July 2006

Abstract
Two pyranocoumarins, 7,7-dimethyl-2(7H)-benzo[1,2-b:4,5-b′]dipyranone and 8,8-dimethyl-2(8H)-benzo[1,2-b:5,4-b′]dipyranone, and three dihydrofuranocoumarins, 2-isopropenyl-1,2-dihydro-8-furo[1,2-f][1]benzopyranone, 2-isopropenyl-2,3-dihydro-6-furo[1,2-e][1]benzopyranone, and 2-isopropenyl-2,3-dihydro-7-furo[2,1-e][1]benzopyranone, were synthesized by an effective pyrone-ring formation in corresponding o-hydroxybenzaldehyde derivatives. And, 2-[1-(hydroxymethyl)vinyl]-1,2-dihydro-8-furo[1,2-f][1]benzopyranone was also synthesized selenium dioxide oxidation.
Diastereoselective Reduction of α-Keto Amides Having trans-2,5-Disubstituted Pyrrolidine as a Chiral Auxiliary
Authors: Kawanami Yasuhiro , Fujita Izumi , Asahara Shouko , Katsuki Tsutomu , Yamaguchi Masaru 
Published: July 2006

Abstract
The reduction of α-keto amides derived from (2R,5R)-trans-2,5-bis(methoxymethoxymethyl)pyrrolidine [(R)-BMOMP, 1] with LiBEt3H or KBEt3H proceeded with high diastereoselectivity (up to 99% ds) to afford the corresponding α-hydroxy amides in good yields. The additive effect of crown ethers or metallic salts on the stereoselectivity was also examined.
Analysis of Isotropic 1H and 13C NMR Shifts of Low-Spin FeIII Complexes: Tetracyano(1,2-ethanediamine)ferrate(III) and Tetracyano(N,N′-dimethyl-1,2-ethanediamine)ferrate(III)
Authors: Kuroda Yoshitaka , Goto Masafumi , Sakai Tomoya 
Published: July 2006

Abstract
1H NMR spectra of low-spin d5 complexes, [FeIII(CN)4(en)]− and [FeIII(CN)4(s-Me2en)]− (en=1,2-ethanediamine, s-Me2en=N,N′-dimethyl-1,2-ethanediamine), were measured at 185–323 K. These complexes showed a non-Curie behavior. The spin states of the complexes were determined by an analysis of the g values from the ESR spectrum of a polycrystalline sample of [FeIII(CN)4(en)]− measured at liquid-helium temperatures. The isotropic shifts for the 1H and 13C nuclei, δiso, were separated into Fermi contact shifts, δcon, and dipolar shifts, δdip and the strong dependence of δiso on the location of ligand nuclei was found to be due to the different δcon as well as δdip. A combination of information concerning ESR and NMR enabled the assignment of the g values obtained from a polycrystalline sample, i.e. gxx=3.15, gyy=1.99, and gzz=0.82, and determination of spin-orbit coupling constant, ζ=160 cm−1.
Kinetic Study on Hydrogenation of Isoquinoline over Supported Ruthenium Catalysts
Authors: Okazaki Hiroshi , Soeda Mahito , Ikefuji Yoshio , Tamura Ryuji , Mochida Isao 
Published: July 2006

Abstract
The hydrogenation of isoquinoline (1) to isomeric decahydroisoquinoline (4) via 1,2,3,4-tetrahydroisoquinoline (2) or 5,6,7,8-tetrahydroisoquinoline (3) was kinetically studied over supported ruthenium catalysts under 50–100 atm hydrogen pressure at 135–170 °C. The results showed that the reaction proceeds mainly via 2 over ruthenium on carbon, and via 2 and 3 competitively over ruthenium on alumina. Such reaction features are explained from the view points of their adsorption and the activation of the molecules on the catalysts based on quantum chemical indices. The acidic nature of alumina support exhibited a preference of nitrogen lone-pair defining the adsorption of substrates, and consequently influencing on the reaction route. The proposed approach distinguished the present catalyst from Raney nickel examined in a previous paper. The noble and base metals may interact differently with the substrate, although both metals are classified as “soft”.
Predictions of the Features of the Potential Energy Surfaces from the Diatomic Constants: A Series of Collinear Abstraction Reactions, H+HX (X=F, Cl, Br, I)
Authors: Tanaka Noboru 
Published: July 2006

Abstract
A new method, to predict the feature of potential energy surface (PES) from the diatomic constants of reactants molecules, is presented. The PES is calculated by using our proposed semi-empirical method (MT method). Based on MT method, a graphical method is introduced to investigate the relations between the features of the PES and the diatomic constants. Using these relations as guideline, the features of the PES for a series of linear abstraction reactions, H+HX=HH+X with X=F, Cl, Br, and I, are deduced in a simple manner. The PES thus deduced are in good agreement with available experimental and theoretical information.
Dielectric Behavior and Intermolecular Association for Octanol Isomers. Existence and Transformation of a Nonpolar Cyclic Polymer
Authors: Shinomiya Toshiomi 
Published: July 2006

Abstract
The equilibrium dielectric constants of ten isomeric C8H17OH and binary mixtures of 1-butanol in four isomeric C8H17OH have been measured at temperatures from 135 to −55 °C. These isomeric C8H17OH can be grouped roughly into three types, namely, more polar, intermediate, and more sterically hindered alcohols. The dielectric behavior of each of the three types can be explained by equilibrium among a linear hydrogen-bonded chain polymer (CHAIN), a free monomer inclusive of a chain dimer and trimer (MONOMER), and a nonpolar cyclic polymer (RING). As the temperature decreases, MONOMER transforms into CHAIN for more polar alcohols. Two transformations, MONOMER into RING at high temperatures and RING into CHAIN at low temperatures, occur for intermediate alcohols. MONOMER transforms into RING and CHAIN can not be observed for more hindered alcohols. However, a transformation of RING into CHAIN can be observed by adding 1-butanol to the more hindered alcohols. CHAIN is most stable. When formation of CHAIN becomes difficult, RING can be formed. The transformation is dependent on temperature, molecular geometry, and the amount of 1-butanol in the mixture.
Spectroscopic Evidence of α,α-Dihydroxy Ketone in Biacetyl Aqueous Solutions
Authors: Miyata Kaori , Nakashima Kenichi , Koyanagi Motohiko 
Published: July 2006

Abstract
From the analysis of emission, excitation, absorption, and 1H NMR spectra of 2,3-butanedione (i.e., biacetyl), it has been established that about two thirds of the molecule in aqueous solutions exists as 3,3-dihydroxy-2-butanone (i.e., a hydrated form of biacetyl). For the first time, two different types of emission are discriminated: Emission is mostly due to the fluorescence spectrum of the monoketone upon irradiation of light with a shorter wavelength than 320 nm while it is due to the strong phosphorescence spectrum of biacetyl itself upon irradiation of light with a longer wavelength than 350 nm. The almost stoichiometric molecular rearrangement from the hydrated (monoketone) form in a water phase to the ordinary (diketone) form in a hydrocarbon phase has been found to take place.
Preparation of Tetraalkylsilanes from Trichloromethylsilane and Trioctylaluminum
Authors: T. Sabourin Edward , Onopchenko Anatoli 
Published: July 2006

Abstract
The synthesis of methyltrioctylsilane has been achieved in a single-step from commercially available trichloromethylsilane and trioctylaluminum. Co-products resulting from alkyl group redistribution are minimized by addition of sodium or lithium halides. Use of potassium or rubidium halides drastically changes the course of the reaction to produce methyldioctylsilane as the major product.
Induced Circular Dichroism and Molecular Orientations of β-Cyclodextrin Inclusion Complexes with 9,10-Anthraquinone and 9,10-Phenanthrenequinone
Authors: Ata Masafumi , Kubozono Yoshihiro , Suzuki Yasunobu , Aoyagi Makoto , Gondo Yasuhiko 
Published: July 2006

Abstract
The induced circular dichroism (ICD) spectra of β-cyclodextrin inclusion complexes with 9,10-anthraquinone and 9,10-phenanthrenequinone have been measured, and the electronic structures and molecular orientations of the guests are discussed in terms of the ICD signs and theoretical results.
The Determination of the Poly(oxyethylene) Oligomer Distribution in a Non-ionic Surfactant by Means of Thin-Layer Chromatography
Authors: Saito Yoshihiro , Sato Takatoshi , Anazawa Ichiro 
Published: July 2006

Abstract
The analytical method for determining the distribution of the polymerization degree of the oxyethylene (OE) chain in commercially available poly(oxyethylene) alkyl ether (CmEn) was investigated by means of thin-layer chromatography with flame-ionization detection (TLC-FID). It was found that the method of calculating the relative response factors of every OE chain to FID could be determined, and the analysis of the distribution of the polymerization degree of the OE chain in commercially available CmEn became possible using the TLC-FID method.
Electronic Properties of New Organic Conductors Based on 2,7-Bis(methylthio)-1,6-dithiapyrene (MTDTPY) with TCNQ and p-Benzoquinone Derivatives
Authors: Imaeda Kenichi , Enoki Toshiaki , Mori Takehiko , Inokuchi Hiroo , Sasaki Mitsuru , Nakasuji Kazuhiro , Murata Ichiro 
Published: July 2006

Abstract
The electronic properties of charge-transfer (CT) complexes based on a new organic donor MTDTPY with TCNQ and p-benzoquinone derivatives (fluoranil (FLL), chloranil (CHL), bromanil (BRL), and DDQ) have been investigated by means of electrical conductivity, thermoelectric power, ESR, and band calculation. β-MTDTPY–TCNQ, MTDTPY–CHL, and MTDTPY–BRL show a metallic electrical conduction. MTDTPY–CHL and MTDTPY–BRL are the first organic metals among the CT complexes with p-benzoquinone derivatives. The metal–insulator (M-I) transition takes place around 110, 240, and 125 K for β-MTDTPY–TCNQ, MTDTPY–CHL, and MTDTPY–BRL, respectively. The sharp ESR linewidth and large anisotropy of the transfer integral for β-MTDTPY–TCNQ and MTDTPY–CHL suggest a one-dimensional electronic property. Thus, the M-I transition for these complexes is considered to be caused by a Peierls instability. MTDTPY–CHL undergoes a first-order phase transition in the semiconducting phase. This phase transition disappears by applying pressure.
Chiral Aryl Grignard Reagents-Generation and Reactions with Carbonyl Compounds
Authors: Kaino Makoto , Ishihara Kazuaki , Yamamoto Hisashi 
Published: July 2006

Abstract
Chiral aryl Grignard reagents are generated in situ from homochiral 2-halobenzaldehyde acetal, t-butyllithium, and magnesium bromide. These reagents react with aromatic aldehydes to moderate diastereoselectivities.
A Facile Synthesis of 4-Hydroxy- and 4-Aminoindoles through Corresponding Indolines
Authors: Tanaka Hideo , Murakami Yasuo , Aizawa Takao , Torii Sigeru 
Published: July 2006

Abstract
2-(2,6-Diaminophenyl)ethanol can be conducted to 4-hydroxyindoline under heating in aqueous 70% phosphoric acid, and to 4-aminoindoline under heating in aqueous 30% sulfuric acid. Both 4-hydroxy- and 4-aminoindoles were obtained by dehydrogenation of the indolines under refluxing in 1,4-dimethylbenzene over palladium on charcoal.
Spectral Studies of Some Coordination Complexes of Pt(II) and Rh(I) with Benzothiazolines
Authors: Garg Archana , Tandon Jagdish Prasad 
Published: July 2006

Abstract
The present paper describes the synthesis and structural features of platinum(II) and rhodium(I) complexes of some benzothiazolines derived by the condensation of various heterocyclic aldehydes viz. 2-pyridinecarbaldehyde, 2-furancarbaldehyde, and 2-thiophenecarbaldehyde. The resulting complexes have been characterized by elemental analyses, conductance measurements and molecular weight determination. The mode of bonding and geometry of these complexes have been suggested on the basis of IR, 1H NMR, electronic spectra, and magnetic studies.
Preparation and Characterization of Rhodium(III) Complexes Containing (2-Aminoethyl)dimethylphosphine (edmp) or 1,2-Bis(dimethylphosphino)ethane (dmpe). Structures of fac-[Rh(edmp)3]3+, trans(Cl,Cl),cis(P,P)-[RhCl2(edmp)2]+, and trans-[RhCl2(dmpe)2]+
Authors: Simonsen Kim P , Suzuki Nahomi , Hamada Masatoshi , Kojima Masaaki , Ohba Shigeru , Saito Yoshihiko , Fujita Junnosuke 
Published: July 2006

Abstract
The fac-[Rh(edmp)3]3+ (edmp=(2-aminoethyl)dimethylphosphine), trans(Cl,Cl),cis(P,P)-[RhCl2(edmp)2]+, and trans-[RhCl2(dmpe)2]+ (dmpe=1,2-bis(dimethylphosphino)ethane) complexes were prepared and the molecular structures were determined by the single crystal X-ray diffraction method. Crystal data and final R values are: fac-[Rh(edmp)3]Br3·3H2O, orthorhombic, Pna21, a=26.750(4), b=10.125(1), c=9.592(1) Å, V=2598.2(5) Å3, Z=4, R=0.039 for 1590 observed unique reflections. trans(Cl,Cl),cis(P,P)-[RhCl2(edmp)2]PF6, monoclinic, P21/a, a=18.197(4), b=12.574(2), c=8.615(1) Å, β=96.59(2)°, V=1958.2(6) Å3, Z=4, R=0.032 for 3379 reflections. trans(Cl,Cl),cis(P,P)-[RhCl2(edmp)2]ClO4, triclinic, P\bar1, a=13.122(2), b=17.952(2), c=12.343(2) Å, α=91.65(2), β=102.46(2), γ=80.74(1)°, V=2802.0(7) Å3, Z=6, R=0.070 for 7513 reflections, trans-[RhCl2(dmpe)2]CF3SO3, monoclinic, P21/a, a=13.166(2), b=24.337(4), c=8.002(2) Å, β=95.95(2)°, V=2550.1(8) Å3, Z=4, R=0.040 for 3201 reflections. It was found that the shorter the Rh–P bond length, the larger the trans Rh–N bond elongation. The mean Rh–P bond distance in trans-[RhCl2(dmpe)2]CF3SO3 (2.337(2) Å) is longer than those in fac-[Rh(edmp)3]Br3·3H2O (2.283(4) Å) and trans(Cl,Cl),cis(P,P)-[RhCl2(edmp)2]PF6 (2.252(2) Å). A series of complexes of trans(X,X),cis(P,P)-[RhX2(edmp)2]+ (X=Cl, Br, I) and trans-[RhX2(dmpe)2]+ (X=Cl, Br) were also prepared and their absorption spectra were compared with one another and with those of the corresponding cobalt(III) complexes.
Synthesis, Magnetic Property, and Crystal Structure of Imidazolate-Bridged Manganese(III)–Copper(II) Dinuclear Complex
Authors: Matsumoto Naohide , Okawa Hisashi , Kida Sigeo , Ogawa Takanori , Ohyoshi Akira 
Published: July 2006

Abstract
The synthesis, crystal structure, and magnetic property of an imidazolate-bridged manganese(III)–copper(II) dinuclear complex [Mn(salen)Cu(A)]BPh4 are described, where [H2salen]=N,N′-disalicylideneethylenediamine, [H2A]=4-(6-methyl-8-oxo-2,5-diazanonane-1,5,7-trienyl)imidazole, and BPh4=tetraphenylborate. The X-ray analysis confirmed an imidazolate-bridged manganese(III)–copper(II) dinuclear structure, in which the coordination geometries of the manganese(III) and copper(II) ions are square pyramid and square planar, respectively. The apical position of the manganese(III) ion is occupied by an imidazolate nitrogen N(3) of the [Cu(A)] moiety with the bond distance of Mn–N(3) 2.165(5) Å. As the temperature is lowered, the effective magnetic moment per molecule decreases gradually from 5.17 B.M. at 300.2 K, reaches the minimum value 4.44 B.M. at 24.9 K, and then increases to 4.73 B.M. at 4.2 K, indicating that antiferro- and ferro-magnetic interactions are co-operative in the complex.
Gallium Coprecipitation Associated with Magnesium for Preconcentration of Trace Metals in Seawater
Authors: Akagi Tasuku , Fuwa Keiichiro , Haraguchi Hiroki 
Published: July 2006

Abstract
The coprecipitation of trace metals with gallium has been investigated in detail especially with respects to the role of magnesium ion in saline or seawater. Gallium does not precipitate even at pH 9 when magnesium ion does not exist. The concentration of gallium in the precipitate increased with increasing that of magnesium in solution. The recoveries of trace metals also showed strong dependence on the concentrations of both gallium and magnesium in the aqueous solution.
A Cross-Coupling Reaction of Methylsulfinylarene
Authors: Wakabayashi Shoji , Tanaka Takakazu , Kubo Yukihiro , Uenishi Junichi , Oae Shigeru 
Published: July 2006

Abstract
Cross-coupling product 2-(2-pyridyl)quinolines were obtained in the reaction of 2-(methylsulfinyl)quinolines and 2-(methylsulfinyl)pyridines with methylmagnesium bromide. Attempts of cross coupling in the reaction of other substrates were unsuccessful.
Electron Transfer Resulting from Excitation of Contact Charge Transfer Complexes of Some Styrene Derivatives and Oxygen. The Role of Oxygen as an Electron Acceptor
Authors: Kojima Masanobu , Sakuragi Hirochika , Tokumaru Katsumi 
Published: July 2006

Abstract
Irradiation of contact charge transfer (CCT) bands (320–370 nm) of 4-methoxystyrene (1a) and 4-methylstyrene (1b) with molecular oxygen in acetonitrile and benzene resulted in the formation of the corresponding cis- and trans-1,2-diarylcyclobutanes (2 and 3) as well as benzaldehydes (4), oxidative cleavage products. In the case of 1b, 7-methyl-1-(4-tolyl)-1,2,3,4-tetrahydronaphthalene (5) and 6-methyl-4-(4-tolyl)-1,2,3,4-tetrahydronaphthalen-1-one (6) were also afforded. The formation of these products is reasonably explained by electron transfer in the excited CCT pair followed by addition of the resulting 1 cation radical to ground-state 1 to form a dimer cation radical; its cyclization leads to the dimeric products and trapping of a cyclic dimer cation radical by oxygen affords ketone 6.
Synthesis of Bis(deoxyribonucleoside) Phosphoromorpholidate Derivatives for Oligodeoxyribonucleotide Preparation by Use of a Selective Phosphitylating Reagent
Authors: Ozaki Hiroaki , Yamoto Shuhei , Maikuma Seiichirou , Honda Kenichi , Shimidzu Takeo 
Published: July 2006

Abstract
Sequence-defined bis(deoxyribonucleoside) phosphoromorpholidate derivatives as stable intermediates to prepare oligodeoxyribonucleotides have been synthesized using morpholinodi(1-tetrazolyl)phosphine as a phosphitylating reagent. The general procedure is composed of following steps (in situ); a) a reaction of 5′-O-protected deoxyribonucleoside with morpholinodi(1-tetrazolyl)phosphine (phosphitylation), b) a reaction of the resulting 5′-O-protected deoxyribonucleoside phosphorobisamidite with the second deoxyribonucleoside (coupling), and c) a nonaqueous oxidation with t-BuOOH (oxidation). In the coupling step, the 5′-O-protected deoxyribonucleoside phosphorobisamidite was selectively reacted with 5′-OH group of the second deoxyribonucleoside, and therefore, a protection of hydroxyl groups of the second deoxyribonucleoside is not necessary. As the resulting P–N bond in the phosphoramidate linkage after oxidation is stable both in acidic and basic conditions, the morpholino function as a phosphoryl protecting group may have many potential use in the synthetic chemistry of oligonucleotide. A thymidine trimer can be obtained in a high yield by extending the present synthetic method.
Use of Axially Chiral 2′-Methoxy-1,1′-binaphthyl-2-carboxylic Acid as Chiral Derivatizing Agent for Discrimination of Enantiomeric Alcohols and Amines by 1H NMR
Authors: Miyano Sotaro , Okada Shin-ichi , Hotta Hiroki , Takeda Masayuki , Suzuki Takatsugu , Kabuto Chizuko , Yasuhara Fujiko 
Published: July 2006

Abstract
Axially chiral 2′-methoxy-1,1′-binaphthyl-2-carboxylic acid (1) was effectively utilized as chiral derivatizing agent for discrimination of enantiomeric alcohols and amines by 1H NMR with the aid of Eu(fod)3. Among a pair of the diastereomeric esters or amides prepared from (aS)-1 and an α-chiral alcohol or amine, the methoxyl protons of the (aS,R)-diastereomer showed the larger lanthanoid-induced downfield shift than those of the (aS,S)-counterpart. Thus, addition of up to 0.5–1.0 equiv amount of Eu(fod)3 caused base-line separation of those protons, allowing determination of the enantiomeric purities and assignment of the absolute configurations of the enantiomeric alcohols and amines. An X-ray crystallographic analysis of the amide ((aS,S)-2) obtained from (aS)-1 and (S)-1-phenylethylamine showed structural resemblance between the amides and esters of 1. Steric models which explain the NMR behavior of the diastereomeric esters and amides are presented based on X-ray analyses. Also reported are two methods to regenerate free acid 1 from amide 2 to afford axially homochiral 1.
High-Resolution 13C NMR Study of (1→3)-β-d-Glucans in the Solid State: DMSO-Induced Conformational Change and Conformational Characterization by Spin-Relaxation Measurements
Authors: Saitô Hazime , Yokoi Motoko 
Published: July 2006

Abstract
High-resolution 13C NMR spectra of a variety of (1→3)-β-d-glucans were recorded in the solid state after lyophilization from DMSO solution in order to study resulting conformations free from the triple-helix conformation. Lyophilization from DMSO solution caused conformational change of laminaran from Laminaria species (‾Dp=38) from the triple helix to the oligomer-type form (form I). On the contrary, single-chain conformation (form II) of high molecular-weight curdlan was unchanged before and after lyophilization from DMSO solution. Further, DMSO induced conformational change of both single-chain (form II) and triplehelical (form III) conformations of acid-degraded curdlan (‾Dp=14) to the form I. These findings support our view that the single-chain conformation is a major form in curdlan powder. We found that these three forms are distinguished by either the 13C spin-lattice relaxation times (T1C’s) of the laboratory frame or proton spin-lattice relaxation times in the rotating frame (T1ρH). In particular, the form I was distinguishable from others by its prolonged T1C values (3.5–12 s) of C-6 carbon. In addition, the T1ρH of the triple helix of annealed curdlan was one order of magnitude longer than that of the single chain, reflecting their difference in the manner of molecular packing.
Laser Flash Photolysis Study of the Magnetic Field Effects on the Biradicals Generated from Aromatic Ketone-Xanthene Bifunctional Chain Molecules
Authors: Tanimoto Yoshifumi , Takashima Masanobu , Itoh Michiya 
Published: July 2006

Abstract
The external magnetic field effects (MFE) on the biradicals generated from the intramolecular photoreactions of bifunctional chain molecules, α-(xanthone-2-carbonyloxy)-ω-(xanthene-2-carbonyloxy)alkanes (XO-n-XH, n=2–12) and Ar-12-XH (Ar=anthraquinone-4-carbonyloxy (AQ), 4-benzoylphenoxy (BP), and 4-acetylphenoxy (AP)) were studied by laser flash photolysis. All biradicals exhibit significant MFE. The simultaneous observation of the effects on the two radicals at the ends of the chain, generated from XO-12-XH, AQ-12-XH, and BP-12-XH, presents unequivocal evidence that the respective two radical centers correlate magnetically each other. The n dependence of the effects on biradicals generated from XO-n-XH indicates that the singlet–triplet degeneracy of the biradical occurs at the chain length of around n=6, i.e., the interradical distance of about 15 Å.
Optical Resolution of a Co(III) Complex of 2-Hydroxy-1,3-propanediamine-N,N,N′,N′-tetraacetic Acid: Crystal Structure of (+)589-Strychnine (2-Hydroxy-1,3-propanediamine-N,N,N′,N′-tetraacetato)cobaltate(III) Sesquihydrate, (+)589-(STC)[Co(dhpta)]·1.5H2O
Authors: Sato Mitsunobu , Yano Shigenobu 
Published: July 2006

Abstract
The 2-hydroxy-1,3-propanediamine-N,N,N′,N′-tetraacetatocobaltate(III) complex has been optically resolved using strychnine nitrate. The crystal structure of the optically active complex with the resolving agent, (+)589-(STC)[Co(dhpta)]·1.5H2O has been determined from three dimensional X-ray diffraction data. The absolute configuration around the cobalt atom, to which two nitrogen and four oxygen atoms in the ligand are bonded nearly octahedrally, is Δ. The six-membered chelate ring adopts the λ-skew boat conformation. The intermolecular hydrogen bonding between the coordinated oxygen atom of the acetate ring and the protonated nitrogen atom of strychnine, which is one of the asymmetric centers, plays an important role in the diastereomeric discrimination. In contrast, the non-coordinated hydroxyl group in the complex ion does not interact directly with the strychnine molecule. The relationship between the absolute configuration around the cobalt center and the circular dichroism has been examined for the optically active complex ion.