Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 61 , Issue 10
Showing 1-50 articles out of 79 articles from the selected issue
  • Yoshihiro Osamura, Takae Takeuchi, Kichisuke Nishimoto
    1988 Volume 61 Issue 10 Pages 3387-3391
    Published: 1988
    Released: June 27, 2006
    JOURNALS FREE ACCESS
    The decomposition mechanisms were studied for ionized species of ethane and propane in the low-energy region by using an ab initio molecular orbital method. Calculations show that rather complex fragmentation processes may occur in addition to a simple cleavage of C–C and C–H bonds. In order to examine the possibility of an elimination of H2 or CH4 from the radical cation of saturated hydrocarbons, the potential energy curves were calculated for both 1,1- and 1,2-eliminations. An energy barrier of 1,2-elimination was estimated to be small, but a 1,1-elimination can also possibly occur. It was also found that a single C–H bond scission of the parent radical cation may occur with the same order of energy for the H2 loss. The present results are qualitatively in a good agreement with the experiments.
  • Akihiro Yoshino, Yasuki Nakashima, Kensuke Takahashi
    1988 Volume 61 Issue 10 Pages 3393-3397
    Published: 1988
    Released: June 27, 2006
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    A kinetic study was conducted on the acid-catalyzed proton–deuteron-exchange reactions of several substituted phenols. The rates of the exchange were determined by using the two-bond isotope shifts (2Δ) on the carbons and the pattern-fitting analyses for the 13C NMR signals. The observed reaction rates can be expressed additively with substituent parameters. The parameters of the para positions are linearly correlated to the σp+ with ρ=−3.6.
  • Yong Li, Kunihiko Tajima, Kazuhiko Ishizu, Nagao Azuma, Kiyonori Miyos ...
    1988 Volume 61 Issue 10 Pages 3399-3402
    Published: 1988
    Released: June 27, 2006
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    X-band and Q-band ESR measurements of Mn(II) ions contained in Japanese cultured marine pearls and pearl oyster (Pinctada fucata) were carried out at room temperature. The ESR spectra observed for the powdered samples of nacreous and prismatic layers revealed the ESR hyperfine structures typical to Mn(II) in an aragonite lattice and a calcite lattice, respectively. The ESR spectra were interpreted with the following spin Hamiltonian.
    \mathscrH=gβH·S+aS·IgnβnH·I+D[Sz2S(S+1)⁄3]+E(Sx2Sy2)
    The resonance fields for all the M=+1⁄2↔M=−1⁄2 ESR transitions were derived, with the third-order corrections all taken into account. The zero-field splitting parameters D and E for Mn(II) ions in these biominerals were estimated by computer simulations of the ESR line shapes. The estimated parameters for the nacreous Mn(II) ion (D=20.8 mT, E=6.9 mT) are apparently different from those for the prismatic Mn(II) ion (D=8.5 mT, E=1.4 mT).
  • Feng-Yuen Dai, Minoru Suzuki, Hiroshi Takahashi, Yasukazu Saito
    1988 Volume 61 Issue 10 Pages 3403-3407
    Published: 1988
    Released: June 27, 2006
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    XRD profiles of as-synthesized Na– and TPA–ZSM-5 were not identical. They became similar to each other, however, when both zeolites were converted into organic-free or organic-contained forms. In terms of the framework topology, Na–ZSM-5 resembled TPA–ZSM-5 but differed from so-called ZSM-8. SEM images revealed the Na–ZSM-5 crystal to exhibit a hexagonal-lath-shaped morphology. Due to the preferred orientations, the intensities of (0k0) and (h0l) reflections were intensified and diminished, respectively. The hexagonal flat plane of the Na–ZSM-5 crystal was (010). Therefore, the 10-membered-ring straight channels were strongly indicated to penetrate perpendicularly to the hexagonal flat plane of the as-synthesized Na–ZSM-5 crystal.
  • Yoshihisa Matsui, Masahiko Fujie, Hiroshi Sakate
    1988 Volume 61 Issue 10 Pages 3409-3415
    Published: 1988
    Released: June 27, 2006
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    The regioisomers of bis- and tris[C(6)-O-sulfonylated] α-cyclodextrins were converted in satisfactory yields to the corresponding C(6)-pyridinio derivatives, which afforded the characteristic splitting patterns of 1H NMR signals available for a regioisomer determination. Electrostatic repulsive interactions between the positively charged pyridinio groups play an important role in the remarkable splitting of the 1H NMR signals observed for some regioisomers.
  • Takayuki Abe, Kingo Itaya, Isamu Uchida, Koichi Aoki, Koichi Tokuda
    1988 Volume 61 Issue 10 Pages 3417-3420
    Published: 1988
    Released: June 27, 2006
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    Platinum ultramicrodisk electrodes 0.8 μm in radius were constructed by anodic electropolishing of a platinum wire followed by sealing it with soft glass. Voltammograms for oxidation of [Mo(CN)8]4−, Fe2−, and [Fe(CN)6]4−, being of a sigmoidal form, were measured at these electrodes and microdisk electrodes with 7.5 μm in radius under the essentially steady-state condition. A voltammogram of Fe2+ at 7.5 μm electrode was drawn out, exhibiting a halfwave potential shifted from the formal potential. This trend was more distinctive for a wave at 0.8 μm electrode. Radii of the electrodes and diffusion coefficients of the electroactive species were determined consistently from the limiting currents. The conventional log-plot showed that electrode reactions of Fe2+ and [Fe(CN)6]4− were, respectively, totally irreversible and almost reversible at these electrodes. Application of the modified log-plot to the voltammograms yielded straight line, of which slope allowed us to evaluate the transfer coefficient and of which intercept gave values of the charge-transfer rate constant. Simulated voltammograms at these values were in good agreement with experimental ones.
  • Michio Noda, Hideki Ichinose, Yasukazu Saito, Yoichi Ishida
    1988 Volume 61 Issue 10 Pages 3421-3423
    Published: 1988
    Released: June 27, 2006
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    Conventional HR-TEM was applied to a nickel fine-particle catalyst that had been prepared by means of a gas-evaporation method. A structure image of the nickel fine particle showed that the particle consisted of an fcc nickel crystal and thin oxide layers of the surfaces. A platinum-deposited nickel fine particle exhibited a moiré pattern, which was analyzed by the use of the Cowley-Moodie dynamical theory of diffraction. An accurate solution of the equations showed that a platinum lattice obliquely piled on a surface lattice of the particle.
  • Ryuichi Arakawa
    1988 Volume 61 Issue 10 Pages 3425-3428
    Published: 1988
    Released: June 27, 2006
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    The metastable ion intensity for the loss of \dotCH2OH from ionized methyl acetate has been measured as a function of the ion-source residence time up to 100 μs by means of the ion-trapping technique. The decay of the metastable ion intensity was adequately interpreted by the use of a prior isomerization mechanism on the basis of RRKM calculations. It was suggested that the intermediate precursor for the generation of CH3CO+ and \dotCH2OH from ionized methyl acetate is not a hydrogen-bridged complex structure, CH3CO–H–OCH2, but a distonic ion structure, CH3\overset+C(OH)O\dotCH2.
  • Sadamu Yamagata, Seiichiro Nakabayashi, Kenneth M. Sancier, Akira Fuji ...
    1988 Volume 61 Issue 10 Pages 3429-3434
    Published: 1988
    Released: June 27, 2006
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    The reaction mechanisms of the photocatalytic oxidation of several different alcohols on TiO2 were investigated by three experimental techniques: spin trapping, photocurrent measurement, and product analysis. The results are interpreted according to the band model of a semiconductor and current doubling. It was found that alcohols with α-hydrogens gave low concentrations of spin adducts since their photoproduced radicals have short lifetimes on TiO2 due to a current-doubling process. Also, it was found that oxygen participated in a radical chain mechanism in the photocatalytic oxidation of ethanol to acetaldehyde.
  • Yoshio Matsunaga, Kiyoshi Nishida
    1988 Volume 61 Issue 10 Pages 3435-3437
    Published: 1988
    Released: June 27, 2006
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    Alkylammonium methane-, ethane-, 1-propane-, and 1-butanesulfonates exhibit a smectic A phase when the cation carries a dodecyl or longer alkyl group. The temperature range of the existence decreases in the following order: methanesulfonates>1-propanesulfonates>ethanesulfonates>1-butanesulfonates. In the last series, the mesophase is entirely metastable. The layer spacing in the 1-propanesulfonate is shorter by about 0.30 nm than that of the corresponding methanesulfonate, even though the alkyl chain length in the anion is increased by 0.25 nm.
  • Shunzo Yamamoto, Mitsuru Kozasa, Yoshimi Sueishi, Norio Nishimura
    1988 Volume 61 Issue 10 Pages 3439-3443
    Published: 1988
    Released: June 27, 2006
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    The zinc-photosensitized reaction of propane has been studied at a wavelength of 307.6 nm, a temperature of 633 K and pressures from about 67 to 40000 Pa. The major products were hydrogen, methane, ethylene, and dimethylbutane, while minor products detected were propylene, isobutane, ethane, butane, and hexane. The yield of hydrogen fell off with time. The quantum yield calculated from the initial rates is about unity and almost independent of the propane pressure, while the quantum yield obtained at 20 min increased with increasing propane pressure and approached about unity at higher pressures. The methane/hydrogen ratio was always smaller than unity and was independent of the propane pressure. The yield of ethylene increased linearly with an increase in that of methane. It has been concluded that the decomposition of propane is initiated through a hydrogen atom abstraction by an excited zinc atom from both the primary and secondary hydrogen of propane. Possible mechanisms are discussed.
  • Haruhiko Yokoyama, Midori Mochida, Yuko Koyama
    1988 Volume 61 Issue 10 Pages 3445-3449
    Published: 1988
    Released: June 27, 2006
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    The ionic partial molar volumes at infinite dilution, V(ion), were determined for several dicarboxylate ions, disulfonate ions, tartrate ions, and [Co(gly)(en)2]2+ (gly=glycinate ion and en=ethylenediamine) from density measurements at 25°C. The values of V(ion) obtained for the divalent anions generally increased with their van der Waals volumes. Significant differences in V(ion) were observed between geometrical isomers with dicarboxylate and disulfonate ions and were attributed to those in both of electrostriction volume and the void space volume around the anions. The former volume was decreased and the latter was increased with increasing distance between two negatively charged groups in the anions. A relatively strong electrostriction behavior of the tartrate ions, compared to the dicarboxylate ions, suggested the presence of an extra electrostriction caused by hydroxyl groups. The electrostriction strength of [Co(gly)(en)2]2+ was significantly large compared to that of [Ni(en)3]2+, rather close to those of [Cr(en)3]3+ and [Co(en)3]3+, and was attributed to the dissymmetrically localized charge distribution in the [Co(gly)(en)2]2+ ion. The effective ionic radii and apparent van der Waals volumes were estimated by using Glueckauf’s equation from the ionic partial molar volume and were discussed in comparison with those calculated from the van der Waals increments of atoms.
  • Shoko Yokoyama, Akiko Kaneko, Tadao Fujie
    1988 Volume 61 Issue 10 Pages 3451-3454
    Published: 1988
    Released: June 27, 2006
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    The surface state of negatively charged mixed micelles prepared by addition of prostaglandin B2 (PGB2) to nonionic heptaethylene glycol dodecyl ether (HED) has been investigated and the surface potential (Δψ) of the micelles has been estimated by measuring the fluorescence intensity of ammonium 8-anilino-1-naphthalenesulfonate (ANS) as a fluorescent probe. Since the binding constant of ANS, k, is dependent on the surface potential of the micelle, the value of Δψ was determined according to the equation Δψ=−59.16log(k0k) at 25°C, where k0 is the k of HED micelle. The value of |−Δψ| increases with increasing mole fraction of PGB2 (XPGB2) and decreases with increasing ionic strength (J). These changes are due to the effects of the negative charge of PGB2 and of ionic atmosphere of Na+, respectively. Surface charge density (σ) was, therefore, determined from Δψ according to the Gouy-Chapman theory, with a result that σ is nearly independent of J and proportional to XPGB2. These results have led to a conclusion that the state of the diffuse layer surrounding the Stern layer on the micelle surface is represented well by the Gouy-Chapman theory as well as a previous result for the system of sodium dodecyl sulfate (SDS) and HED. The value of |−σ| for PGB2 micelle is less than that for SDS micelle, which suggests that PGB2 forms a loosely packed micelle.
  • Ping Wang, Takehiko Mori, Chikako Nakano, Yusei Maruyama, Hiroo Inokuc ...
    1988 Volume 61 Issue 10 Pages 3455-3459
    Published: 1988
    Released: June 27, 2006
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    An organic compound TSeCn-TTF [tetrakis(alkylseleno) tetrathiafulvalenes] with n=2, crystallizes in the monoclinic space group P21a, a=23.218(5), b=8.960(3), c=10.489(3) Å, β=96.61(2)°, V=2168(1) Å3, and Z=4; the compound with n=4 crystallizes in the triclinic space group P\bar1, a=9.198(1), b=10.539(2), c=8.248(2) Å, α=113.16(2), β=96.02(2), γ=90.61(2)°, V=729.9(3) Å3 and Z=1. The molecule with n=2 has a bent structure, like a boat; and the molecule with n=4 has a structure in which each of the four alkyl chains is stretched towards different directions. The temperature dependence of electrical resistivity and the charge-carrier mobility have been measured, and the resistivities at room temperature are ρa⁄ρb⁄ρc=3.3×109⁄2.0×109⁄6.0×1011 and 2.2×1011⁄1.0×1011⁄1.3×1011 (Ω cm) for TSeC2-TTF and TSeC4-TTF, respectively. The quite isotropic character in the resistivities of a TSeC4-TTF crystal may originate from its rather strange molecular structure.
  • Masayuki Suzuki, Masahisa Fujita, Takeshi Takemura, Hiroaki Baba
    1988 Volume 61 Issue 10 Pages 3461-3466
    Published: 1988
    Released: June 27, 2006
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    The phosphorescence spectra, lifetimes, and quantum yields of pyridine and its methyl derivatives, 2-picoline, 3-picoline, and 2,6-lutidine in the vapor phase have been measured with the aid of a specially designed circuit by means of control of the voltage imposed on the photomultiplier. The phosphorescence spectrum shifts to shorter wavelengths with increasing methylation. The phosphorescence lifetimes and quantum yields of pyridine and the picolines are of the order of 1 μs and 10−7 both values being one order of magnitude smaller than the corresponding values for the lutidine. These observations are explained by assuming that (1) the lowest triplet state (T1) and the next lowest triplet (T2) are of 3(π,π*) and 3(n,π*) types respectively, (2) the energy gap between T1 and T2 is small, especially in the unsubstituted pyridine, and (3) the potential energy curve for T1 is distorted according to the energy gap, as the result of a pseudo-Jahn-Teller type of interaction between T1 and T2.
  • Makoto Morita, Kazutoshi Iwamoto, Manabu Sen\={o}
    1988 Volume 61 Issue 10 Pages 3467-3470
    Published: 1988
    Released: June 27, 2006
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    Sustained oscillation and birhythmicity have been observed when aqueous solutions of potassium permanganate, potassium nitrite, formic acid, and methanol were mixed in a continuous-flow stirred tank reactor. A detailed phase diagram is shown. This new oscillator is composed of non-halogen compounds and the first example of the nitrogen-based oscillator.
  • Hayao Sakamoto, Masaakira Kamada, Norinobu Yonehara
    1988 Volume 61 Issue 10 Pages 3471-3477
    Published: 1988
    Released: June 27, 2006
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    The contents and distributions of arsenic, antimony, and mercury in geothermal water samples taken from various geothermal areas in Japan were investigated. Since the existing forms of arsenic, antimony, and mercury in geothermal waters are complex and can change during sample storage, it is difficult to determine all of the chemical forms. In this study, therefore, the arsenic(III+V), antimony(III+V), and total mercury contents were determined. In geothermal water, there is a high positive correlation between the contents of arsenic and antimony. However, there is no correlation at all between the contents of mercury and arsenic, or between those of mercury and antimony. It can be assumed that mercury behaves differently from either arsenic or antimony in geothermal water.
  • Masanobu Watanabe, Yuichi Masuda, Izumi Motoyama, Hirotoshi Sano
    1988 Volume 61 Issue 10 Pages 3479-3484
    Published: 1988
    Released: June 27, 2006
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    The unstable adducts of ferrocene and methylferrocene and the stable adducts of biferrocene, diferrocenylmethane, 1,2-diferrocenylethane, and [n]ferrocenophane (n=2, 3) with HgX2 (X=Cl, Br, I, and BF4) were studied by means of 57Fe-Mössbauer and high-resolution solid-state 13C NMR spectroscopies. The large quadrupole splitting (Q. S.) values in the 57Fe-Mössbauer and the large low-field shifts in the 13C-CP-MAS NMR, spectroscopy suggest the presence of a direct chemical bond between the Fe and Hg atoms.
  • Kyoko Adachi, Norio Ichinose, Chiaki Shimizu, Ken Okamoto
    1988 Volume 61 Issue 10 Pages 3485-3489
    Published: 1988
    Released: June 27, 2006
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    Bivalves and plankton samples were collected monthly for one year from brackish Lake Hamana in Japan, and contents of 5,8,11,14,17-eicosapentaenoic acid (EPA) and 5,8,11,14-eicosatetraenoic acid (arachidonic acid, AA) and their weight percentage to total fatty acids were determined by fluorescence high-performance liquid chromatography. The results regarding bivalves showed that the EPA and AA levels are approximately ten times higher in liver than in adductor on the average for one year, and are remarkably dependent upon the season. The seasonal changes of EPA and AA contents in bivalve liver are seemingly related to those of plankton, which are the diet of bivalves. From these facts, it can be seen that plankton is the main origin of EPA and AA in bivalve bodies and supply these fatty acids all the way up to humans through a food chain.
  • Mamoru Shimoi, Yuki Fujinawa, Hiroshi Ogino, Kan Kanamori, Kiyoyasu Ka ...
    1988 Volume 61 Issue 10 Pages 3491-3496
    Published: 1988
    Released: June 27, 2006
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    The structures of cis- and trans-dinitrobis(1,4-butanediamine)cobalt(III) nitrates were determined by the single-crystal X-ray diffraction method. cis-[Co(NO2)2(tmd)2]NO3 (tmd=H2N(CH2)4NH2) is monoclinic with the space group P21a; the cell constants are a=23.878(4), b=8.403(1), c=16.675(3) Å, β=103.24(1)°; Z=8, and the final R value was 0.051. trans-[Co(NO2)2(tmd)2]NO3·H2O is triclinic with the space group P\bar1; the cell constants are a=9.753(3), b=13.909(4), c=6.327(1) Å, α=102.07(2), β=91.05(2), γ=87.83(3)°; Z=2, and the final R value was 0.058. Both complexes have a slightly distorted octahedral geometry around the cobalt center. The conformations of the seven-membered chelate rings have twist-chair and chair forms for the cis and trans complexes, respectively.
  • Taro Tsubomura, Shigenobu Yano, Sadao Yoshikawa
    1988 Volume 61 Issue 10 Pages 3497-3501
    Published: 1988
    Released: June 27, 2006
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    Stable complexes of the type [Co(aldonato)(en)2]+, where en is ethylenediamine and aldonato is the diacid anion of D-gluconic acid or L-mannonic acid, were prepared by the reaction of aldonic acid lactones with rac-[Co(CO3)(en)2]+. Two diastereomers (Δ and Λ) have been separated by ion-exchange chromatography from each of the aldonato complexes. These complexes were characterized by NMR, electronic absorption, and circular dichroism spectra. The structures of all four complexes were found to have an aldonato ligand which coordinates bidentately through an oxygen atom of the carboxylato group and an oxygen atom of the deprotonated hydroxyl group on C(2).
  • Min-Ho Jung, Masamichi Atoh, Kazuo Kashiwabara, Junnosuke Fujita
    1988 Volume 61 Issue 10 Pages 3503-3509
    Published: 1988
    Released: June 27, 2006
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    Two new quadridentate phosphine ligands 1,1,11,11-tetraphenyl-4,8-diaza-1,11-diphosphaundecane (pp-232PNNP) and (3S,9S)-3,9-dimethyl-1,1,11,11-tetraphenyl-4,8-diaza-1,11-diphosphaundecane (SS(C)-pp-232PNNP), and several their cobalt(III) complexes were prepared and characterized. The RS(N) isomers of trans-[CoCl2(pp- or SS(C)-pp-232PNNP)]+ were formed by oxidation of cobalt(II) complexes of these ligands in dichloromethane with chlorine, while the RR,SS(N), and RR(N) isomers of the pp-232PNNP and SS(C)-pp-232PNNP complexes, respectively, were derived from the corresponding carbonato complexes and hydrochloric acid. The [Co(O-O)(pp- or SS(C)-pp-232PNNP)]n+ (O–O= CO32−, C2O42−, C5H7O2) complexes yielded only a cisβ isomer. The stereochemistry of the complexes was discussed on the basis of the absorption, circular dichroism and NMR spectra.
  • Yuki Fujii, Homare Shinohara, Masahiro Mikuriya, Shigeo Kida, Yoshie K ...
    1988 Volume 61 Issue 10 Pages 3511-3517
    Published: 1988
    Released: June 27, 2006
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    Ternary cobalt(III) complexes with a general formula β2-[Co(tfac2en)(L-aa)], where tfac2en is the titled Schiff base ligand and L-aa denotes L-ala, L-leu, L-phe, L-tyr, and L-trp, were synthesized and separated into two diastereoisomers. On the bases of X-ray crystal analysis of the L-phe complex, CD, and 1H and 19F NMR spectra, the structure of (−)435- and (+)435-isomers was determined to be Λ- and Δ-cis-β2-forms, respectively, and preferred conformation of the coordinated L-amino acidates was assummed to be h-form in solution. All the complexes showed stereoselectivity for the Λ-isomer in acetone and methanol, but the selectivity decreased or reversed with addition of water. The solvent-dependent stereoselectivity was explained in terms of steric repulsion and hydrophobic interligand interactions between CF3 group of tfac2en and side chain of L-aa.
  • Sumio Kaizaki, Mariko Hayashi, Keisuke Umakoshi, Shun-ichiro Ooi
    1988 Volume 61 Issue 10 Pages 3519-3523
    Published: 1988
    Released: June 27, 2006
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    The crystal structure of the title compound has been determined from the X-ray diffraction data. This complex crystallizes in the monoclinic space group with unit-cell parameters of a=17.724(2), b=8.084(1), c=14.025(2) Å, β=95.06(1)°, and Z=4, and with a space group of P2⁄c. The structure converged to R=0.043 for 2898 reflections. In the complex anion, the chromium is coordinated by the sexadentate cydta ligand, producing a distorted octahedral CrN2O4 geometry. The glycinate chelates of the in-plane G(girdling) rings in the CrN2O2 plane are more distorted with respect to the Cr–O bond lengths and internal bond angles than are those of the out-of-plane R(relaxed) rings in the CrNO3 plane. This may be responsible for the lability to dissociation of the G-ring acetate chelates. A close proximity of non-bonded hydrogen atoms (ca. 1.90 Å) is found between the methylene groups in the R ring and the cyclohexane ring. There are two nonequivalent sodium ions in the unit cell, which link the cydta complex anions to form an anion layer along the c axis.
  • Yoshihito Ikariyama, Shigeru Yamauchi, Masuo Aizawa, Tomoaki Yukiashi, ...
    1988 Volume 61 Issue 10 Pages 3525-3530
    Published: 1988
    Released: June 27, 2006
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    A unique micro-enzyme sensor for the determination of glucose has been prepared by incorporating glucose oxidase into the micropores of a platinized microelectrode. The electrode diameter is in the range from 10 μm to 200 μm. The detection limit is 5×10−7 mol L−1 for glucose, and an excellent linearity is obtained in the concentration range from 5×10−7 to 10−2 mol L−1 in the case of micro-enzyme electrode whose diameter is larger than 50 μm. In the case of micro-enzyme electrode whose diameter is 10 μm, the detection limit for glucose is 10−5 mol L−1, and the linearity is observed in the concentration range from 10−5 to 5×10−2 mol L−1. The sensor responds to every glucose sample of different concentration in 3 s or less, and the coefficients of variation for glucose (1 mM) determination were within 2%. The sensor output was stable over 4 weeks. This unique microfabrication approach to micro-enzyme electrodes enables the immobilization of intact enzyme molecules by a simple procedure.
  • Takeo Akiyama, Kohji Kato, Masatsugu Kajitani, Yoshio Sakaguchi, Junko ...
    1988 Volume 61 Issue 10 Pages 3531-3537
    Published: 1988
    Released: June 27, 2006
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    The photochemical introduction of trifluoromethyl group with CF3Br in aromatic and heteroaromatic rings was investigated for 9 compounds. Naphthalene, anthracene, anisole, N,N-dimethylaniline, ferrocene, benzo[b]thiophene, isoquinoline, and N-methylpyrrole gave trifluoromethylated products in 6.5–100% yields. In one step from uracil, a pharmacologically important 5-trifluoromethyluracil can be synthesized by this method in 11% yield. Based on the mechanistic study carried out for the naphthalene–CF3Br–CH3CN system, the reaction is found to proceed via the electron transfer from an excited singlet state of naphthalene to CF3Br.
  • Setsuo Saito, Shigeya Sumita, Kumiko Iwai, Hirotoshi Sano
    1988 Volume 61 Issue 10 Pages 3539-3547
    Published: 1988
    Released: June 27, 2006
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    Mesobiliverdin IXα dimethyl ester (7) was obtained by hydrogenation of protobiliverdin IXα dimethyl ester (8). Zinc 5-oxamesoporphyrin IX dimethyl ester tetrafluoroborate (6) was prepared by the cyclization of 7 with zinc acetate in acetic anhydride followed by a treatment with aqueous sodium tetrafluoroborate. Bis(pyridine) mesoverdohemochrome IXα dimethyl ester (4) was obtained by the cyclization of 7 with both iron(II) sulfate and iron(III) chloride in acetic anhydride containing a small amount of pyridine. Bis(tosylmethyl isocyanide) mesoverdohemochrome IXα dimethyl ester (5) was prepared by the addition of excess tosylmethyl isocyanide (TsCH2NC) to 4. Both 4 and 5 reacted with ammonia to give iron(III) 5-azamesoporphyrin IX dimethyl ester (10). The Mössbauer spectra of bis(pyridine) verdohemochromes (4, 13, and 14) snowed doublet peaks having parameters of δ=0.41–0.43 mm s−1 and ΔEQ=1.24–1.26 mm s−1, indicating that the oxidation states of the central irons of these complexes are iron(II). Bis(TsCH2NC) verdohemochromes (5, 15, and 17) showed single peaks having parameters of δ=0.21–0.28 mm s−1. Unstable intermediate and stable final bis(TsCH2NC) octaethyl verdohemochromes, obtained by the addition of TsCH2NC to 4, were compared with the 1H NMR and Mössbauer spectra.
  • Masato Yoshida, Tatsuro Yoshida, Nobumasa Kamigata, Michio Kobayashi
    1988 Volume 61 Issue 10 Pages 3549-3552
    Published: 1988
    Released: June 27, 2006
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    The heptafluoropropylations of several substituted thiophenes with bis(heptafluorobutyryl) peroxide were studied. The orientations of the heptafluoropropylation were examined and compared with those of usual electrophilic substitution. The method for the preparation of 3-heptafluoropropylthiophene was also explored.
  • Yoshinobu Nagawa, Midori Goto, Koichi Honda, Hiroshi Nakanishi
    1988 Volume 61 Issue 10 Pages 3553-3557
    Published: 1988
    Released: June 27, 2006
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    Molecular structures of the title compounds, which belong to the class of peri-substituted naphthalenes, have been determined by means of X-ray diffraction. Tetraisopropyl 1,1′-(1,8-naphthylene)bis[1H-1,2,3-triazole-4,5-dicarboxylate] (1), monoclinic, space group C2⁄c, a=35.034(3), b=9.717(1), c=18.504(1) Å, β=96.43(1)°, Z=8; Diisopropyl 1-(1-naphthyl)-1H-1,2,3-triazole-4,5-dicarboxylate (2), monoclinic, space group P21n, a=16.246(2), b=10.115(1), c=12.390(1) Å, β=96.67(1)°, Z=4. The dihedral angles between the mean plane of the naphthalene ring and that of the triazole ring are 88° and 85° for 1 and 2, respectively. The naphthalene framework of 1 is much more distorted than that of 2 because of a steric repulsion between the two triazole rings with bulky ester groups of 1.
  • Tomomichi Ishikawa, Hidehiko Nishizuka, Tadashi Kawai
    1988 Volume 61 Issue 10 Pages 3559-3564
    Published: 1988
    Released: June 27, 2006
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    Polymers anchoring 3-unsubstituted 2-oxazolidinone were prepared and their complex formation with phenol and mercury(II) acetate were investigated. Preformed poly(4-hydroxystyrene) was treated with tris(2,3-epoxypropyl) isocyanurate to give a polymer containing 2-oxazolidinone residues within the limits of 57.7 mol%. Polymers carrying 2-oxazolidinone were also prepared through the homopolymerization and copolymerization of 4-(2-oxo-5-oxazolidinylmethoxy)phenyl acrylate. The effective concentration of 2-oxazolidinone residue in the polymers, which is accessible to phenol, was determined on the assumption that the polymer-bound 2-oxazolidinone and phenol formed a 1 : 1 complex. 2-Oxazolidinone and a mercury atom formed a 2 : 1 complex; this relation on the molar ratio applies to all forms of complexes between the mercury atom and the 2-oxazolidinone residue in the polymers.
  • Taeko Izumi, Satoshi Murakami, Akira Kasahara
    1988 Volume 61 Issue 10 Pages 3565-3568
    Published: 1988
    Released: June 27, 2006
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    Keto crown ethers that contain ferrocene or ruthenocene and 2,6-disubstituted pyridine unit as part of the major ring have been reported. These keto crown ethers were synthesized by a reaction of 1,1′-metallocenedicarbonyl dichloride (ferrocene or ruthenocene) with 2,6-bis[ω-hydroxyoligo(oxyethylene)-α-ylmethyl]pyridine by using a high-dilution method. Their complexing ability with metal cations was measured by a solvent-extraction method, and was found to be poor with alkali metal cations but excellent with Ag+, In3+, and Zr4+ cations.
  • Akira Kaneko, Akihiko Tomoda, Mitsuo Ishizuka, Hisao Suzuki, Ryoka Mat ...
    1988 Volume 61 Issue 10 Pages 3569-3573
    Published: 1988
    Released: June 27, 2006
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    Thermal stabilities of the colored forms at 80°C and photochemical fatigue resistances against coloration–discoloration cycles were measured in PMMA thin film, using 14 derivatives of fulgide with different heterocyclic structures. The indolyl (12), oxazolyl (13), and thiazolyl (14) derivatives showed very low thermal degradabilities (TD≤1.5%/day) while 12 and pyrazolyl derivative (9) showed low photochemical fatigues (PF≤0.2%/cycle), as compared with the furyl (1), thienyl (2), and pyrrolyl (3) derivatives. However, many of them featured low photo-responsiveness and low absorptivities for coloration on UV irradiation.
  • Nobumasa Kamigata, Akira Satoh, Tetsuya Kondoh, Masayuki Kameyama
    1988 Volume 61 Issue 10 Pages 3575-3580
    Published: 1988
    Released: June 27, 2006
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    The palladium(0)-catalyzed reaction of arylazo aryl sulfones with olefins in benzene at 80°C gave aryl-substituted olefins in good yield. Diarylpalladium(II) species was proposed as an intermediate in this reaction.
  • Masao Okubo, Yoshito Inatomi, Naoki Taniguchi, Kaori Imamura
    1988 Volume 61 Issue 10 Pages 3581-3585
    Published: 1988
    Released: June 27, 2006
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    In reactions of ArN(MgBr)2 with o-MeO- and o-halo-substituted nitrobenzenes, types and yields of products were different from those in its reactions with m- and p-substituted substrates. Condensation (leading to unsymmetrical azoxy- and azobenzenes), o-substituent replacement, and nuclear substitution took place. Relative yields of products were greatly affected by substituents and reaction conditions. o-MeO and o-F favor replacement, while o-Cl, o-Br, and o-I favor substitution. Replacement and/or substitution predominate when small molar excess of reagent and low concentration are used, while condensation predominates when large molar excess of reagent and high concentration are used, which phenomenon is mechanistically discussed.
  • Makoto Sasaki, Tatsushi Murae, Hisaaki Matsuo, Toshiyuki Konosu, Naoko ...
    1988 Volume 61 Issue 10 Pages 3587-3605
    Published: 1988
    Released: June 27, 2006
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    A compound having a skeleton of an antitumor quassinoid, bruceantin, was prepared according to the following strategy; 1) construction of ring ABC from ring AB by cyclization of a hindered 1,5-diketone; 2) construction of ring E (ether ring) by opening of a 12,13-epoxide ring followed by attack of oxygen at C-20 toward C-13; 3) formation of ring D (hemiacetal ring) by treatment of a 7α-hydroxy-16-al dimethyl acetal with PPTS.
  • Shigekazu Kanemoto, Seijiro Matsubara, Kazuhiko Takai, Koichiro Oshima ...
    1988 Volume 61 Issue 10 Pages 3607-3612
    Published: 1988
    Released: June 27, 2006
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    Bis(trimethylsilyl) peroxide (BTSP) serves as an effective oxidant of alcohols in the presence of chromium(VI) or ruthenium(II) complexes as catalysts in dichloromethane. Selective oxidation of primary alcohols in preference to secondary ones using RuCl2(PPh3)3 as a catalyst is also described.
  • Itaru Hamachi, Yoshiaki Kobuke, Iwao Tabushi
    1988 Volume 61 Issue 10 Pages 3613-3618
    Published: 1988
    Released: June 27, 2006
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    By using a strongly hydrophilic NADH model, BzNAHCOOK in the external electron donor, a transmembrane electron transport to the internal acceptor, K3[Fe(CN)6] through the flavolipid (1) was observed. BzNAHCOOK was proved to be an appropriate NADH model in the transmembrane electron transport study because of (i) the very low permeability through the bilayer membrane (k=1.0×10−3 s−1) and (ii) the slow hydration rate (k=1.1×10−5 s−1). The artificial liposome modified with the flavolipid showed a 6–7 times more efficient electron flux conversion from BzNAHCOOK to K3[Fe(CN)6] than the liposome modified with the ubiquinone 10, a biologically important electron carrier. In association with the electron transport, electrochemical oxidation and reduction peaks of the flavolipid incorporated into the liposomal membrane were observed clearly by using Hg-electrode.
  • Kazuo Doyama, Takayuki Higashii, Fumio Seyama, Yoshiteru Sakata, Soich ...
    1988 Volume 61 Issue 10 Pages 3619-3627
    Published: 1988
    Released: June 27, 2006
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    Seventeen pyrimidinopurinophanes in which a pyrimidine and a purine ring are fixed with different mode of stacking were prepared. The synthesis was carried out by stepwise introduction of two bridging chains. In the final ring closure reaction, two isomers, i.e., isomers bridged at 9-position of a purine ring and those having the bridge at 7-position of a purine ring were obtained. The structures of the isomers were determined on the basis of 1H NMR, IR, and UV spectra and X-ray analysis. In 1H NMR spectra the bridge protons of the pyrimidinopurinophanes show complex multiplets, in contrast to the first order splittings in singly bridged reference compounds. This shows clearly the fixation of the conformations of the present cyclic compounds at room temperature. All of the pyrimidinopurinophanes show relatively large hypochromism (H) values. Even the compounds 2a2d, 4, and 6 where the two base rings are not stacked in parallel, but inclined with the dihedral angle of around 50°, show H values of 10–20%. The H values did not change among the compounds 1c, 1e1g, and 3 which have similar parallel-stacking structures of the two base rings. The results are well explained by the simplified equation of Ts′o et al.
  • Akio Kamimura, Noboru Ono
    1988 Volume 61 Issue 10 Pages 3629-3635
    Published: 1988
    Released: June 27, 2006
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    Denitrohydrogenation reaction of aliphatic nitro compounds with tributyltin hydride (Bu3SnH) is accelerated in the presence of radical initiators. ESR and electrochemical measurements reveal that the reductive cleavage of the carbon–nitrogen bond proceeds not via anion radicals of nitro compounds such as SRN1 reaction but via β-scission of (tributylstannyloxy)nitroxyl radicals. The relative reactivities of tin radicals toward substituted α-nitrocumenes, α-nitroethylbenzenes, and α-nitropropiophenones exhibits excellent Hammett correlations with positive ρ values. This tendency has also been found in the reaction of benzyl halides with tin radical. These results suggest that the carbon–nitrogen bond breaking from nitroxyl radical intermediates should take place in rate-determining step for the reaction.
  • Hidenori Chikashita, Megumi Ishibaba, Keiji Ori, Kazuyoshi Itoh
    1988 Volume 61 Issue 10 Pages 3637-3648
    Published: 1988
    Released: June 27, 2006
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    The reaction of 2-lithiobenzothiazole with a variety of electrophiles such as aldehydes, ketones, carboxylic esters, lactones, nitriles, and amides afforded the expected addition and substitution products. Trimethylsilyl chloride readily reacted with the benzothiazolyl anion to give 2-trimethylsilylbenzothiazole, while common alkyl halides including primary iodide and benzyl halides, as well as epoxides, did not react with the anion. This characteristic nucleophilicity of the anion was also demonstrated by its reaction with phenacyl halides and 5-chloro-2-pentanone leading to the formation of benzothiazolyl-substituted small-ring ethers. In order to demonstrate the value of 2-lithiobenzothiazole as a masked formyl anion, 2-(α-hydroxyalkyl)benzothiazoles were transformed into α-hydroxy carbonyl compounds in three reaction steps without masking the α-hydroxy groups. Quaternization of various 2-(α-hydroxyalkyl)benzothiazoles with methyl iodide in DMF afforded the corresponding 2-(α-hydroxyalkyl)-3-methylbenzothiazolium iodides in high yields and the subsequent alkylation or reduction of the C=N+ link was readily accomplished with organolithium and Grignard reagents or sodium borohydride leading to the corresponding 2-(α-hydroxyalkyl)-3-methylbenzothiazolines with or without another 2-substituents. Hydrolysis of former compounds performed in aqueous acetonitrile, buffered to pH 7 and containing AgNO3, gave the desired α-hydroxy ketones.
  • Masahiro Murakami, Masahiko Inouye, Michinori Suginome, Yoshihiko Ito
    1988 Volume 61 Issue 10 Pages 3649-3652
    Published: 1988
    Released: June 27, 2006
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    Some reactions of (triphenylphosphine)gold(I) enolates and homoenolates, which are respectively prepared by the reaction of trimethylsilyl ethers of enols and cyclopropanols with (triphenylphosphine)gold(I) chloride in the presence of cesium fluoride, are described. The aldol reaction of (triphenylphosphine)gold(I) enolates with carbonyl compounds is efficiently promoted by Lewis acids such as titanium tetrachloride and diethylaluminum chloride to produce β-hydroxy carbonyl compounds. (Triphenylphosphine)gold(I) enolate reacts with phenyl acetylene to afford (triphenylphosphine)gold(I) phenylacetylide in good yield. Reaction of (benzoylmethyl)(triphenylphosphine)gold(I) (3a) with chlorotrimethylsilane produces α-(trimethylsilyloxy)styrene and (triphenylphosphine)gold(I) chloride, which is the reverse of the formation of 3a. Gold(I) enolate undergoes an isocyanide insertion reaction into the linkage of carbon and gold. (2-Benzoylethyl)(triphenylphosphine)gold(I) reacts with 2-methyl-2-propanethiol to afford (triphenylphosphine)gold(I) t-butyl sulfide together with propiophenone.
  • Masaaki Ueki, Takashi Saito, Jun Sasaya, Shigeru Ikeda, Hidekazu Oyama ...
    1988 Volume 61 Issue 10 Pages 3653-3657
    Published: 1988
    Released: June 27, 2006
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    The formation and coupling of the dimethylphosphinothioic mixed anhydrides of protected amino acids can be performed in alcohol solvents. Sparingly soluble protected C-terminal segments of vasoactive intestinal peptide (VIP) up to the heptapeptide stage were synthesized by this technique and fully characterized.
  • Masato Machida, Koichi Eguchi, Hiromichi Arai
    1988 Volume 61 Issue 10 Pages 3659-3665
    Published: 1988
    Released: June 27, 2006
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    Barium hexaaluminate, BaO·6Al2O3, exhibited excellent heat resistance in maintaining a large surface area. Preparation from hydrolysis of metal alkoxides was a superior process in deriving the large surface area of BaO·6Al2O3, to that from mixtures of BaCO3⁄γ-Al2O3. Direct formation of BaO·6Al2O3 phase at low temperature plays the key role in retaining the fine particle size. The amount of water added for hydrolysis and the aging period of hydrolyzed precursors strongly influenced the surface area of alkoxide-derived BaO·6Al2O3. These effects of the preparation conditions originated from the difference in microstructure and chemical structure of the hydrolyzed precursors. Monodispersed fine precursor particles with high oxide content generated large surface area BaO·6Al2O3.
  • Yoh Sano
    1988 Volume 61 Issue 10 Pages 3667-3672
    Published: 1988
    Released: June 27, 2006
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    Using the light-scattering theory of Rayleigh–Gans, theoretical expressions were derived for the state of the polarization of light scattered by anisotropic spherical particles in the case of linearly polarized incident light with its electric vector inclined by an angle ψ to the scattering plane. The azimuth angle of the ellipse of the light scattered is a function of only the scattering angles, θ and ψ; the ellipticity of the ellipse of the scattered light is always equal to zero, meaning that the scattered light is linearly polarized for linearly polarized incident light. The degree of polarization of the scattered light, P, defined as the ratio of the polarized component to the total intensity of the scattered light, depends on the intrinsic anisotropy, pm, the relative refractive index of the sphere to the solvent, m, and θ together with the angle ψ. Although P for isotropic spherical particles is always equal to 1 at any θ, P for anisotropic spherical particles is smaller than 1.0, but close to 1.0 if the incident light is unpolarized or linearly polarized with ψ=30°. If ψ is smaller than 30°, P varies from 1.0 to 0, depending strongly on the pm and m of the anisotropic sphere. It has been suggested that the determination of P as a function of ψ and θ would provide good information about the optical intrinsic anisotropy of anisotropic spherical particles.
  • G. K. Mallik, T. K. Pal, T. Ganguly, S. B. Banerjee
    1988 Volume 61 Issue 10 Pages 3673-3680
    Published: 1988
    Released: June 27, 2006
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    External heavy atom effect on the emission spectra of naphthalene, phenanthrene, and chrysene by perturbers dihalobenzenes are investigated to estimate different nonradiative rate constants associated with the depletion of the singlet and the triplet states of the fluorescers. The bimolecular fluorescence quenching rate constant kq has been evaluated at 300 K by applying Stern–Volmer relation. The dihalobenzene quenchers have triplet states lying below the singlet states of the fluorescers and the overall quenching rate kq is composed of two rate constants, namely, the intramolecular intersystem crossing rate kqISC and the singlet–triplet energy transfer rate constant kqST. The relative magnitudes of the two rate constants kqISC and kqST have been examined in the light of the energy conditions controlling the associated processes. At 77 K, the phosphorescence decay curve of the fluorescers in the presence of dihalobenzenes is biexponential and the triplet decay of the perturbed fraction of the fluorescers is exponential. It is concluded that at the low temperature, heavy atom interaction in the systems studied mainly proceeds through CT mechanism. Speculative suggestion has been made to account for enhancement of phosphorescence emission of polyfused arenes in EtOH solution.
  • Sushmita Sen, Krishnakoli Kali, Subir K. Roy
    1988 Volume 61 Issue 10 Pages 3681-3687
    Published: 1988
    Released: June 27, 2006
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    The dielectric permittivities ε|| and ε and the refractive indices ne, no of five 4-cyano-4′-alkyl-1,1′-bicyclohexyls (CCH 2, CCH 3, CCH 4, CCH 5, CCH 7 where 2, 3, 4, 5, 7 means ethyl, propyl, butyl, pentyl, heptyl respectively) have been measured at different temperatures in the nematic and isotropic phases. The orientational order parameter from the refractive indices data, calculated from (1) Vuks’ method and (2) Neugebauer’s method were in good agreement. At any reduced temperature, the order parameter for CCH 2 is largest and that of CCH 7 is smallest and those for the others are in between them. Unlike for cyanobiphenyls or cyclohexylbenzenes, the dielectric permittivity ε|| is obtained for \overset→E⊥\overset→H and ε for E||H, where \overset→E is the electric and \overset→H is the magnetic field, and has been explained as due to these molecules having negative diamagnetic anisotropy. The dielectric anisotropy, Δε and optical anisotropy Δn for all the CCH’s is much less than that of the corresponding CB or PCH molecules. All the CCH’s show pretransitional permittivity just above the transition temperature TNI.
  • Ishwar Singh, Pratap Singh Kadyan
    1988 Volume 61 Issue 10 Pages 3689-3692
    Published: 1988
    Released: June 27, 2006
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    Reaction behavior of bismuth(III) and indium(III) with 2,4,6-tris(2-hydroxy-4-sulfo-1-naphthylazo)-1,3,5-triazine trisodium salt (THT) is established under various conditions. Bismuth(III) forms a 2 : 3 dark red complex (absorption maximum at 530 nm) with the reagent at pH 4–6.5. Indium(III) reacts with THT to form a 1 : 2 dark red complex at pH 3–4.7 (λmax 530 nm) and a 1 : 3 purple blue complex at pH ca. 10.5 (λmax 620 nm). The molar absorptivities for the color reactions are 5.5×104 for bismuth(III), 8.4×104 for indium(III) at pH 3.5 and 7.9×104 L·mol−1·cm−1 for indium(III) at pH ca. 10.5 (in sodium carbonate medium). Other physicochemical characteristics of the complexes are established. A number of foreign ions are tested for their interference and the use of masking agents wherever necessary is tabulated.
  • K. G. Varshney, A. A. Khan, A. R. Khan
    1988 Volume 61 Issue 10 Pages 3693-3697
    Published: 1988
    Released: June 27, 2006
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    A new inorganic ion exchanger based on antimony has been prepared viz. antimony(V) arsenatophosphate, which has shown a peculiarly high thermal stability and selectivity for alkaline earth and transition metal ions. As a result, its column use has been demonstrated for the separation of mercury from magnesium and zinc and of iron from other transition metals. A tentative formula has also been proposed for the material, on the basis of its chemical analysis and other characterization studies.
  • Ivan A. Natchev
    1988 Volume 61 Issue 10 Pages 3699-3704
    Published: 1988
    Released: June 27, 2006
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    Acetylation of D-, DL-, and L-3-amino-2-pyrrolidinone (1) to the 3-acetamido derivative 2 and treatment with ethyl methylphosphinate afforded the addition product 3. Strict selectivity was observed in the enzyme-catalyzed hydrolysis with the enzyme phosphodiesterase I, acylase, glutaminase, and α-chymotrypsin. The ester 7 and 1,2-azaphospholidine (8) were isolated by esterification of L-phosphinothricin (6).
  • Ivan. A. Natchev
    1988 Volume 61 Issue 10 Pages 3705-3709
    Published: 1988
    Released: June 27, 2006
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    The natural tripeptide antibiotic “Bialaphos” (5) has been synthesized by condensation of the protected L-phosphinothricin (1) with the dipeptide alanylalanine ethyl ester. The dicyclohexylcarbodiimide method has been used, followed by enzyme-catalyzed hydrolysis. Analogously, a cyclic analogue and the phosphac-peptide (phosphinic amide type) analogue (14) of the antibiotic (5) have been found to possess antitumour activity.
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