bluuebunny/crossref_metadata_2025_split huggingface dataset:
Magnetic Properties and Crystal Structures of Binuclear Copper(II) Complexes with Heterocyclic Thione Donors of 1,3-Bis(hydroxymethyl)-2-imidazolidinethione and 1-Hydroxymethyl-3-methyl-2-imidazolidinethione
Authors: Tokii Tadashi , Nakahara Shinji , Hashimoto Noriyuki , Koikawa Masayuki , Nakashima Michio , Matsushima Hideaki 
Published: July 2006

Abstract
A new series of binuclear copper(II) complexes with 1,3-bis(hydroxymethyl)-2-imidazolidinethione, [Cu(RCOO)(HL1)]2 (where R = CH3 (1), C6H5 (2), 2-CH3C6H4 (3), 4-CH3C6H4 (4), 2-ClC6H4 (5), and 2-BrC6H4 (6)), and with 1-hydroxymethyl-3-methyl-2-imidazolidinethione, [Cu(RCOO)(L2)]2 (where R = CH3 (7), 2-CH3C6H4 (8), and 4-CH3C6H4 (9)), have been prepared. The magnetic susceptibility data of complexes 1—9 conform to the usual dimer equation with the −2J values ranging from 227 to 992 cm−1. Crystal structure analyses of 3, 4, 7, and 9 revealed that two copper atoms are linked by two alkoxo-bridges with separations of 3.015(3)—3.069(3) Å in each complex. The coordination around each copper atom of the complexes is essentially a square planar configuration with one sulfur and two alkoxo-oxygen atoms of HL1 or L2 and one oxygen atom of carboxylates. Each alkoxo-group asymmetrically bridges with the Cu1–O1 bonds (1.90—1.92 Å), which are shorter than the Cu1′–O1 bonds (1.93—1.97 Å). The −2J values for complexes 3, 4, 7, and 9 are much better correlated with the Cu1′–O1 bond distances than with the alkoxo-bridging Cu1–O1–Cu1′ angles.
Magnetic Properties of Some Triangular Trinuclear Complexes of [Ru2M(μ-CH3COO)6(μ3-O)(py)3]n+ with a Diamagnetic Ion M
Authors: Kobayashi Hanako , Uryû Norikiyo , Mogi Iwao , Miyamoto Ryo , Ohba Yasunori , Iwaizumi Masamoto , Sasaki Yoichi , Ohto Akihiro , Ito Tasuku 
Published: July 2006

Abstract
The magnetic susceptibilities and the electron paramagnetic resonances (EPRs) of four complexes: [Ru2M(μ-CH3COO)6(μ3-O)(py)3]n+ (M = Zn(II), Mg(II), and Ru(II): n = 0; and Rh(III): n = 1) salts were observed. These are magnetic dimers of Ru(III). The results were analysed under the assumptions that the strong antiferromagnetic superexchange interaction (J3) is working through μ3-O bridge and that the antiferromagnetic superexchange interaction (J1) through μ-(CH3COO)2–M(dia)–(CH3COO)2 is very weak compared to those of double μ-acetato bridges (J2’s) and of the μ3-O bridge between Ru(III) ions considering the Goodenough–Kanamori rule. The fitting assuming a probability for each path showed the antiferromagnetic interactions through μ3-O were much stronger than that of the symmetric trimer M = Ru(III). J1/k’s were −1.4 — −6.5 K (J1; −97 — −450 m−1), J2/k’s were −40 — −110 K (J2; −2780 — −7640 m−1), and J3/k’s were −500 — −900 K (J3; −34700 — −62500 m−1). Samples of M = Rh(III) and Ru(II) seem to show weak ferromagnetism.
Linear Chain Compounds of Molybdenum(II) Acetate Linked by Pyrazine, 4,4′-Bipyridine, and 1,4-Diazabicyclo[2.2.2]octane
Authors: Handa Makoto , Mikuriya Masahiro , Kotera Takanori , Yamada Kori , Nakao Tadahiro , Matsumoto Hiroki , Kasuga Kuninobu 
Published: July 2006

Abstract
A series of linear-chain complexes of molybdenum(II) acetate linked by bidentate bridging ligands, [Mo2(O2CCH3)4L]n (L = pyrazine (pyz), 4,4′ -bipyridine (4,4′-bpy), and 1,4-diazabicyclo[2.2.2]octane (dabco)), have been prepared, and their crystal structures determined by an X-ray diffraction method. It has been shown that the relatively weak coordinations of the bridging ligands at the axial positions of Mo2(O2CCH3)4 (Mo–N = 2.619 (8)—2.658(6) Å) can effectively control the arrangement of the dimer units to give chain structures with good linearities. No significant interactions between the dimer units have been observed.
Kinetic Study of the Binding of Ca2+ to S-100 Proteins
Authors: Matsuda Sadayuki 
Published: July 2006

Abstract
The effects of trifluoperazine (TFP) and mastoparan (MP) on the rate of Ca2+-release from bovine brain S-100 proteins (s-100a.a′, S-100b) were determined using a stopped-flow method. No remarkable difference was observed in the rate constants for the case of S-100a.a′ and S-100b at pH = 7.14. The addition of MP decreased the rate constants to one fifth, while TFP had little influence.
Preparation and Structure of Sterically Protected Diethynylphosphines and Dibutadiynylphosphines
Authors: Toyota Kozo , Shibata Manabu , Yoshifuji Masaaki 
Published: July 2006

Abstract
Sterically protected diethynyl(2,4,6-tri-t-butylphenyl)phosphines and (2,4,6-tri-t-butylphenyl)bis(4-trimethylsilyl-1,3-butadiynyl)phosphine were prepared and their structures were analyzed by X-ray crystallography. The aromatic rings in these molecules are distorted to boat or more likely envelope forms in the crystals. Large distortion in the –P–C≡C– moieties was also observed.
Synthesis and Dynamic Stereochemistry of Tris(2-methyl-1-azulenyl)methyl Cation and the Corresponding Methane Derivative. Evidence That the Conjugative Effect Largely Contributes to the Transition State of the Ring Flipping
Authors: Ito Shunji , Morita Noboru , Asao Toyonobu 
Published: July 2006

Abstract
The stable carbocation, tris(2-methyl-1-azulenyl)methyl hexafluorophosphate (4·PF6−) was prepared by a hydride-abstraction reaction of the corresponding methane derivative, tris(2-methyl-1-azulenyl)methane (5). The dynamic stereochemistry of 4 and 5 was studied based on the temperature-dependent 1H NMR spectra, which were analyzed by a flip mechanism; the steric effect of the three 2-methyl groups was also investigated by comparing it with that of the 3,3′,3″-trimethyl analogue, tris(3-methyl-1-azulenyl)methyl hexafluorophosphate (1b·PF6−). The threshold rotation mechanism for 4 was a two-ring flip, in contrast to a one-ring flip for 1b, and the activation energies for 4 (78.0 and 73.4 kJ mol−1) were higher than those for 1b due to increased crowding in the transition state for the rotation. Although the activation energies for 5 (49.9 and 43.2 kJ mol−1) were lower than those for 1b, the mechanism for 5 was also a two-ring flip. The mechanism was variable between one- and two-ring flip processes due to a steric effect of the three 2-methyl groups. These results indicate that a conjugative interaction between the central cation and the three azulene rings largely contribute to the transition state of the ring flipping as well as to the ground state.
Direct Construction of the Chroman Structure from 1,3-Diene. Regioselective Protonation of Acyclic Polyene
Authors: Matsui Makoto , Yamamoto Hisashi 
Published: July 2006

Abstract
The regioselective protonation of acyclic polyene was achieved, dependent on the choice of catalyst. The addition of myrcene to trimethylhydroquinone, using boron trifluoride–diethyl ether (1/1), predominantly gave a spiro structure. When (+)-10-camphorsulfonic acid was used as a catalyst, the major compound produced was chroman.
Preparation of Phosphoamino Acid Derivatives with Acid Stable O-Phosphono-Protection for the Boc-Mode Solid-Phase Synthesis of Phosphopeptides
Authors: Wakamiya Tateaki , Saruta Kunio , Yasuoka Jun-ichi , Kusumoto Shoichi 
Published: July 2006

Abstract
Boc-phosphoamino acid derivatives with O-[di(4-nitrobenzyl)- or dicyclohexylphosphono]-protection were prepared for application to the Boc-mode solid-phase synthesis of phosphopeptides. These protecting groups are both stable to TFA, but removable with a combination of trifluoromethanesulfonic acid and methylthiobenzene in TFA. Of these derivatives, Nα-Boc-O-(dicyclohexylphosphono)serine and Nα-Boc-O-(dicyclohexylphosphono)threonine were obtained as crystalline compounds to be favorably utilized as starting materials for solid-phase synthesis using an automated peptide synthesizer. On the other hand, Nα-Boc-O-(dicyclohexylphosphono)tyrosine and all of the O-[di(4-nitrobenzyl)]phosphono derivatives were prepared as crystalline cyclohexylammonium or dicyclohexylammonium salts.
Synthesis of 3-Oxosapriparaquinone, a Diterpene from Salvia prionitis Hance
Authors: Matsumoto Takashi , Takeda Yoshio , Soh Kimiko , Matsumura Hiroyuki , Imai Sachihiko 
Published: July 2006

Abstract
12-Acetoxy-5,10-friedo-4,5-seco-abieta-3,5(10),6,8,11,13-hexaene prepared from (+)-dehydroabietic acid, was converted into a natural rearranged abietane-type diterpene, 3-oxosapriparaquinone, via 12-benzoyloxy-3-hydroxy-5,10-friedo-4,5-seco-abieta-5(10),6,8,12-tetraene-11,14-dione by a series of reactions: hydroboration–oxidation, benzoyl peroxide oxidation, Jones oxidation, and alkaline hydrolysis.
Reaction of Mono-, Di-, and Trichloronitrobenzenes with N-Methyl Substituted Cyclic Tertiary Amines under High Pressure
Authors: Ibata Toshikazu , Shang Muhong , Demura Tetsuo 
Published: July 2006

Abstract
The reactions of mono-, di-, and trichloronitrobenzenes with 1-methylpyrrolidine under high pressure gave products of demethylation and ring-opening through a quaternary pyrrolidinium chloride intermediate formed by the SNAr reaction. On the other hand, the reactions with 1-methylpiperidine and 4-methylmorpholine gave only demethylation products. The selectivities of the reactions of 1-methylpyrrolidine with these chloronitrobenzenes were found to be effected by the neighboring substituent to the pyrrolidinium group.
Synthesis and Structure of 1,4-Dimethoxy and 1,4-Dimethyl-9-(trifluoromethyl)triptycenes
Authors: Toyota Shinji , Watanabe Yoichi , Yoshida Hiroyuki , Oki Michinori 
Published: July 2006

Abstract
As the first example of triptycenes carrying a trifluoromethyl group at the 9-position, the title compounds were synthesized by the Diels–Alder reaction of 9-(trifluoromethyl)anthracene with a substituted benzyne. Rotational barrier of the 9-trifluoromethyl group is more than 25 kcal mol−1 according to the 19F NMR measurements at high temperatures. X-Ray analyses of these compounds reveal that molecules have some unusual bond lengths and angles ascribable to steric interactions between the 1-substituent and the 9-trifluoromethyl group. Comparison of these structural parameters with those of the 9-t-alkyltriptycenes reported previously reveals that the out-of-plane bending of the 1-methoxy group in the latter is unusual. We attribute this anomaly to the presence of the C–H···O hydrogen bond.
Crystal Structures and Hydrogen Bonding in One-Dimensional Chains of 4,5-Dicyanoimidazole and 4,5-Dichloroimidazole
Authors: Nagatomo Shigenori , Takeda Sadamu , Tamura Hatsue , Nakamura Nobuo 
Published: July 2006

Abstract
The crystal structure of 4,5-dicyanoimidazole ((CN)2Imd) was determined by an X-ray diffraction at room temperature; monoclinic, P21/a, a = 7.259(2), b = 7.529(1), c = 10.0972(9) Å, β = 102.74(1)°, V = 538.2(2) Å3, Z = 4, R = 0.043, and Rw=0.066 for 1090 observed reflections. Crystal structure of 4,5-dichloroimidazole (Cl2Imd) was redetermined; tetragonal, P41212, a = 6.843(4), c = 24.236(7) Å, V = 1134(1) Å3, Z = 8, R = 0.043, and Rw = 0.058 for 427 observed reflections. Molecules in Cl2Imd and in (CN)2Imd are linked by intermolecular N–H···N hydrogen bonds to form one-dimensional chains. The hydrogen bonds in Cl2Imd are formed between the ring nitrogen atoms, while those in (CN)2Imd are between the ring and the cyano nitrogens. The hydrogen bond distance (3.051(2) Å) of N···N in (CN)2Imd is long, compared with that (2.800(6) Å) in Cl2Imd. The weak hydrogen bond in (CN)2Imd was also indicated by IR and 15N CP/MAS NMR spectra.
Fluorescence Properties of Pyrylium and Thiopyrylium Salts
Authors: Parret Sylvie , Morlet-Savary Fabrice , Fouassier Jean-Pierre , Inomata Kiyoshi , Matsumoto Takeo , Heisel Francine 
Published: July 2006

Abstract
Due to their very substantial fluorescence emission, pyrylium and thiopyrylium salts are widely used as laser dyes and photosensitizers. This paper deals with the fluorescence properties (quantum yields and wavelengths of the fluorescence maxima as well as the lifetimes of the singlet excited states) of eight pyrylium and ten thiopyrylium salts, with special emphasis on the effect of α and γ substitutions of the heterocycle.
Diffusion Process of a Liquid Crystal Probed by the Transient Grating Method
Authors: Ohta Kaoru , Terazima Masahide , Hirota Noboru 
Published: July 2006

Abstract
Translational diffusion of MBBA (N-(4-methoxybenzylidene)-4-n-butylaniline) in the nematic and isotropic phases is investigated by the transient grating (TG) method. The origin of the TG signal due to the population grating is attributed to the spatial variation of the order parameter and, as a result, the time dependence of the signal reflects the diffusion of the cis form of MBBA, not of the trans form. In the nematic phase, the diffusion constant parallel to the director orientation, D||, is always larger than the perpendicular one, D⊥. The obtained values are 2.2—2.5 times larger than previously reported ones measured by using a photosensitive probe molecule in the liquid crystal. The anomaly previously reported near the nematic–isotropic phase transition temperature is not observed, and the diffusion constant in the isotropic phase is close to the average value of the both components, 1/3(D + 2D⊥). The experimental values are also compared with the ones calculated from two theoretical expressions by Franklin, and Chu and Moroi.
Highly Sensitive and Low Loss Ion-Exchanged Glass Optical Waveguides Constructed by the Successive Doping of K+ and Ag+ Ions
Authors: Chen Xiao-Min , Itoh Kiminori , Murabayashi Masayuki 
Published: July 2006

Abstract
A K+ ion-exchanged glass optical waveguide (OWG) was combined with an Ag+ ion-exchanged glass OWG on one substrate by tapered velocity coupling to obtain a low loss and highly sensitive ion-exchanged OWG system. The relative sensitivity of the Ag+-doped region was more than 1000 times per unit length (the reference here being spectroscopic measurements with normal incidence of monitoring light). The attenuation of the guided light was 3—5 dB cm−1 at the highly sensitive part. Stability against heat and against UV-irradiation were investigated also.
Stereoselective Formation and Characterization of S-Bridged Dinuclear Λ- and Δ-[Co{Co(didentate-N,S)3}(d-pen-N,O,S)]-Type Complexes (didentate = 2-Aminoethanethiolate, l-Cysteinate, and d-Penicillaminate (d-pen))
Authors: Yonemura Toshiaki , Nakahira Sayuri , Ama Tomoharu , Kawaguchi Hiroshi , Yasui Takaji , Okamoto Ken-ichi , Hidaka Jinsai 
Published: July 2006

Abstract
Novel S-bridged dinuclear cobalt(III) complexes having different absolute configurations in [Co(didentate-N,S)3] moieties, Λ- and Δ-[Co{Co(didentate-N,S)3}(d-pen-N,O,S)]+ or 2− (didentate = 2-aminoethanethiolate (aet), l-cysteinate (l-cys), and d-penicillaminate (d-pen)), were prepared stereospecifically. The dinuclearizing reaction of ΔLll-fac(S)-[Co(l-cys-N,S)3]3− with [CoCl(NH3)5]2+ and d-penicillaminate proceeded with configurational retention in the [Co(l-cys-N,S)3] moiety, while the reaction using the Co(II) ion instead of [CoCl(NH3)5]2+ was accompanied by a configurational inversion in the [Co(l-cys-N,S)3] moiety. The occurrence of the configurational inversion was related to the intramolecular N–H···O hydrogen bonds between two ligands in the formation process of the dinuclear complexes. The newly prepared dinuclear complexes were characterized on the basis of their electronic absorption, CD, 13C NMR, and IR spectral data. Electrochemical measurements of [Co{Co(didentate-N,S)3}(d-pen-N,O,S)]+ or 2− gave two redox waves at ca. −0.61 V and −0.85 to −1.04 V (vs. Ag/AgCl). The former wave corresponds to the Co(III)/Co(II) redox of the [Co(S)3(d-pen-N,O,S)] moiety, and the latter one to that of the [Co(didentate-N,S)3] moiety.
Highly Acidic Extractant, 4-Benzoyl-3-phenyl-5-isoxazolone: The Synergistic Extraction of Alkaline Earth and Alkali Metals Combined with Trioctylphosphine Oxide or Bis(diphenylphosphinyl)methane
Authors: Le Quyen T H , Umetani Shigeo , Sasaki Takayuki , Tomita Takeshi , Matsui Masakazu 
Published: July 2006

Abstract
The synergistic extraction of alkaline earth (Mg2+, Ca2+, Sr2+, and Ba2+) and alkali metals (Li+ and Na+) with a highly acidic extractant, 4-benzoyl-3-phenyl-5-isoxazolone (HPBI), combined with a synergist, trioctylphosphine oxide (TOPO) or bis(diphenylphosphinyl)methane (BDPPM), has been examined. The results were compared with those of the analogous extractants, 4-benzoyl-3-methyl-1-phenyl-5-pyrazolone (HPMBP) and 3-methyl-1-phenyl-4-trifluoroacetyl-5-pyrazolone (HPMTFP) which are also highly acidic extractants derived from heterocyclic compounds. Owing to the strong acidity of HPBI (pKa = 1.23), alkaline earths were extracted quantitatively from a very low pH region. Especially, alkaline earths were readily extracted at pH 2—3 with the bidentate phosphine oxide, BDPPM, as a synergist. The extraction of Li+ and Na+ with HPBI and TOPO was inferior to that with HPMBP and HPMTFP, though their acidity is weaker. In contrast to the excellent extractability of HPBI, its separation was poor. The extractability and separability are discussed in terms of the molecular structure, particularly the distance of the two donating oxygens.
Synthesis and Characterization of Highly Pure Form of Sodium Salt of Anionic, Thiomalatogold(I) Complex with Antiarthritic Activity. Analogs of Anionic, Thiomalatosilver(I) Complex with Antimicrobial Activity
Authors: Nomiya Kenji , Yokoyama Hiroshi , Nagano Hitomi , Oda Munehiro , Sakuma Sadatoshi 
Published: July 2006

Abstract
Sodium salt of anionic Au(I) complex with a trianion of thiomalic acid tma3− (H3tma = HOOCCH(SH)CH2COOH), known as an effective antiarthritic drug, was prepared in highly pure form by one-step synthesis from NaAuCl4 and tma3− in aqueous solution. The reaction consisted of a reduction of Au(III) by tma3− and the following complexation of Au(I) with tma3− ligand. The disulfide species of tma3− formed by this reduction was removed by passing through an anion-exchange resin column and the contaminating NaCl by passing through a gel filtration column. The tma–Au(I) complex was also prepared by another reaction based on ligand exchange of the intermediate complex AuCl(thiodiglycol) with tma3−. It was purified using the anion-exchange resin and gel filtration columns. The target compound, finally isolated in 30% yield in highly pure form, has been characterized by complete elemental analyses, TG/DTA, FT-IR, 1H and 13C NMR spectroscopies, and molecular weight was determined in aqueous solution by molmass measurement based on the cryoscopic method combined with dissociation degree determination based on the [Na+] measurement in equilibrium state using a Na+-ion selective electrode. This Au(I) complex was an oligomer with a formula of {Na2[Au(tma)]·1.75H2O}n (n = 3—10; MW = 1260—4220). This polymerization degree, low in comparison with previously proposed data, was determined in the neutral aqueous solution without any other electrolytes under the concentration range CNa = 0.914—182.9 mmol dm−3. The tma–Au(I) complex exists in an oligomeric form both in the solid and in aqueous solution. The properties of the oligomeric tma–Au(I) complex were compared with those of the previously reported complex and a commercially available sample, and also with those of the recently prepared, oligomeric tma–Ag(I) complex with antimicrobial activity.
Spectrophotometric Determination of Zirconium with 5,7-Diiodo-8-hydroxyquinoline
Authors: Nijhawan Monica , Chauhan Rakam Singh , Kakkar Lajpat Rai 
Published: July 2006

Abstract
5,7-Diiodo-8-hydroxyquinoline (diiodo-oxine) has been used as an analytical reagent for the spectrophotometric determination of zirconium with which it forms a yellow colored complex (1 : 2) in dilute hydrochloric acid solution. The complex is extractable into chloroform from 0.1—0.2 mol dm−3 HCl showing an absorption maximum at 417.5—421 nm with a molar absorptivity of 1.87 × 104 dm3 mol−1 cm−1 and Sandell sensitivity equal to 4.8 × 10−3 μgZr cm−2. Beer’s law holds good in the range 0—5 μgZr cm−3, with a standard deviation ±0.006 and relative mean error ±0.36%. The method is simple, selective and sensitive.
Complexes of 15,15′-Trimethylenebis(1,4,7,10,13-pentaazacyclohexadecane-14,16-dione) with Bivalent Metal Ions. Complexation Equilibria in an Aqueous Solution
Authors: Kodama Mutsuo 
Published: July 2006

Abstract
With polarographic and potentiometric methods, the complexation equilibria of 15,15′-trimethylenebis(1,4,7,10,13-pentaazacyclohexadecane-14,16-dione) [abbreviated to bis(dioxo[16]aneN5)] with Cu2+, Cd2+, Hg2+, and Pb2+ ions were investigated systematically. It was found that bis(dioxo[16]aneN5) reacts with Cu2+ ion affording a 2 : 1 ratio binuclear complex, designated Cu2L4+ or [Cu2H−4L]°, but in the reactions with Cd2+, Hg2+, and Pb2+ ions it forms 1 : 1 ratio complexes, ML2+. Comparison of formation constants for the complexes of the latter bivalent metal ions with those of the parent 1,4,7,10,13-pentaazacyclohexadecane-14,16-dione [abbreviated to dioxo[16]aneN5] showed that the attachment of the second dioxo[16]aneN5 moiety always enhances the complexation ability of the dioxo[16]aneN5 ligand considerably, suggesting the formation of sandwich-type complexes, where the metal(II) ion is located between the two cyclic pentaamine moieties.
Successive Chemical Reactions Accompanying a One-Electron Oxidation of a {MNO}6-Type Nitrosyl Complex, Pentachloro(nitrosyl)ruthenate(2−), and a Characterization of the Product Species
Authors: Ooyama Dai , Nagao Noriharu , Howell F Scott , Mukaida Masao , Nagao Hirotaka , Tanaka Koji 
Published: July 2006

Abstract
A one-electron oxidation species of the title complex, [Ru(NO)Cl5]−({RuNO}5-type nitrosyl complex), converted into cis-[Ru(NO)Cl4(CH3CN)]−({RuNO}6-type nitrosyl complex) at low temperature (5 °C) in the dark. The product species could be isolated and characterized. An X-ray structure determination showed a remarkably short N–O bond distance of the Ru–NO moiety: l(N–O) = 0.998 Å, l(Ru–N) = 1.787(5) Å, ∠Ru–N–O = 175.1(6)°. Under room light at 25 °C, the complex underwent a facile nitrosyl photoelimination to give trans-[RuCl4(CH3CN)2]−, the structure of which was also established. During the course of the reactions, two other unidentified species were confirmed to exist by cyclic voltammetry.
Synthesis of 1,3-Dioxane-Bridged Pyropheophorbide-Diimide and Pyropheophorbide Dimer and Their Intramolecular Electron and Energy Transfer
Authors: Osuka Atsuhiro , Marumo Shinji , Wada Yukihisa , Yamazaki Iwao , Yamazaki Tomoko , Shirakawa Yoshihiro , Nishimura Yoshinobu 
Published: July 2006

Abstract
1,3-Dioxane-bridged pyropheophorbide–diimide dyads and pyropheophorbide dimer were synthesized by simple acid-catalyzed reactions of methyl pyropheophorbide d with diimide-substituted diols and with pentaerythritol, respectively. 1,3-Dioxane-bridged bacteriopyropheophorbide–diimide was similarly prepared from bacteriopyropheophorbide a. Intramolecular electron-transfer and energy-transfer reactions in these models have been studied by picosecond fluorescence measurements.
Effect of Hexacyanoferrate(III) on Mycobacterium smegmatis 7Fe Ferredoxin: Further Evidence for Formation of a 6Fe(2 × [3Fe–4S]) Ferredoxin
Authors: Imai Takeo , Kamata Kazuya , Saito Hiroshi , Urushiyama Akio 
Published: July 2006

Abstract
Addition of potassium hexacyanoferrate(III) to Mycobacterium smegmatis 7Fe ferredoxin resulted in the formation of a new 6Fe(2 × [3Fe–4S]) ferredoxin, which was verified by the iron content and resonance Raman spectra of the highly purified preparation. The results suggest that the 4Fe cluster in the native ferredoxin was converted into a 3Fe cluster. The new 3Fe cluster produced was found to be similar in structure to the native 3Fe cluster as judged by the Raman spectra. The produced 6Fe(2 × [3Fe–4S]) ferredoxin was further degraded into apoferredoxin upon application of additional hexacyanoferrate(III).