Masahiro Kinoshita  Yuko Okamoto  Fumio Hirata 《Journal of computational chemistry》1997,18(10):1320-1326

We have developed an algorithm for solving the reference interaction site model (RISM) equations for water near a solute molecule with many atomic sites (interaction sites). It is a hybrid of the Newton–Raphson and Picard methods and is judiciously constructed. Various considerations are given so that the computer time can be saved as much as possible. The robustness and high efficiency of the algorithm has been demonstrated for calculating hydration free energies of Met-enkephalin (a peptide with 75 sites) with different conformations. The Jacobian matrix is treated as part of the input data, and it has been found that the same matrix can be used for a considerably large set of different conformations of the solute molecule. © 1997 John Wiley & Sons, Inc. J Comput Chem 18: 1320–1326, 1997  相似文献   

    

Koichi Tanaka  Shinji Honke  Zofia Urbanczyk-Lipkowska  Fumio Toda 《European journal of organic chemistry》2000,2000(18):3171-3176

The novel, chiral, host compounds 8 and 9 were derived from tartaric acid. Inclusion complexation with these host compounds permitted highly efficient resolution of some aliphatic alcohols ( 10 − 13 ). The symmetrical dimer host compound 8 is effective for optical resolution of alcohols 10 , 12 , and 13 by a combination of enantioselective inclusion complexation and distillation techniques. The unsymmetrical dimer host compound 9 is effective for optical resolution of cyanohydrin 11 . The crystal structures of the inclusion complexes were analyzed by X-ray diffraction methods in order to elucidate the mechanism of the efficient chiral recognition in the inclusion crystals.  相似文献   

    

Akihiro Ito  Yukiharu Ono  Kazuyoshi Tanaka 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2000,112(6):1114-1117

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Alexander Steblyanko  Wonmun Choi  Fumio Sanda  Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2000,38(13):2375-2380

A bifunctional five‐membered cyclic carbonate was synthesized from carbon dioxide and diglycidyl terephthalate, and its polyaddition with alkyl diamines were carried out in DMF at room temperature to obtain the corresponding poly(hydroxyurethane)s with M_n s in the range of 6300–13200 in good yields. The structures of the obtained polymers were confirmed by IR and NMR spectroscopy and their glass‐transition and decomposition temperatures were observed at 3–29 °C and 182–277 °C, respectively. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 2375–2380, 2000  相似文献   

    

Akiko Inagaki  Toshifumi Takemori  Masako Tanaka  Hiroharu Suzuki 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2000,112(2):411-414

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Manabu Kirino  Fumio Sanda  Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2000,38(18):3428-3433

Novel aliphatic aminimides were synthesized from the corresponding carboxylic acid esters, 1,1‐dimethylhydrazine, and epoxides in 54–95% yields. Bulk polymerization of glycidyl phenyl ether (GPE) with 3 mol % of the aminimides was evaluated by DSC as a model process for curing of epoxy resin. All the aminimides showed no exothermic DSC peak below 120 °C but showed sharp exothermic peaks above 137 °C, indicating good thermal latency. Good relationships were observed between the calculated bond length from the carbonyl carbon to the α‐carbon of the aliphatic group (R C), DSC onset temperatures, and the thermal dissociation temperatures (T_d 's) of the aminimides. The aminimide with a longer R C bond length showed lower T_d and DSC onset temperature, that is, higher activity. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 3428–3433, 2000  相似文献   

    

Israel Goldberg  Zafra Stein  Koichi Tanaka  Fumio Toda 《Journal of inclusion phenomena and macrocyclic chemistry》1991,10(1):97-107

The crystal structures of the 2,2-di(p-hydroxyphenyl)propane host and its 1:1 adducts withm-andp-cresol guests have been studied. The preferential complexation of this host withp-cresol overm-cresol is related to the opposite trend exhibited by 1,1-di(p-hydroxyphenyl)cyclohexane; both hosts can separate effectively the two cresols from their liquid mixture by crystalline inclusion. A plausible explanation of the different inclusion features is provided by examining the intermolecular association in the corresponding solids. The analysed structures are stabilized by strong and continuous H-bonding between the constituent entities along two dimensions, and by weak van der Waals forces along the third axis. The p-cresol complex of the title host reveals a unique arrangement within and a more efficient packing of the layered structure, and thus represents a more stable and less soluble crystal lattice than itsm-cresol analog.Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82099 (8 pages).  相似文献   

    

Y Kohama  K Tanaka  N Murayama  M Itoh  T Suda  S Takae  T Mimura 《Chemical & pharmaceutical bulletin》1992,40(11):3017-3020

The immunosuppressive profile of Bacillus stearothermophilus UK563 component, Fr.5-B, is presented in in vitro studies. Fr.5-B (0.1-1000 ng/ml), provided it was added at the initiation of mixed leukocyte reaction (MLR), inhibited dose-dependently the incorporation of tritiated thymidine ([3H]TdR) into mouse spleen cells and human peripheral blood lymphocytes. Even the addition of Fr.5-B 48 h after the onset of culture suppressed mouse MLR, unlike cyclosporin A (CYA). Fr.5-B significantly inhibited cytotoxic T lymphocyte generation determined by [3H]TdR-release micro-cytotoxicity assay by using mouse mastocytoma P815 as targets. Moreover, this component decreased dose-dependently the expression of class II major histocompatibility molecules (Ia) on mouse peritoneal macrophages induced by concanavalin A supernatant. The present results revealed the unique immunosuppressive property of Fr.5-B which was different from that of CYA.  相似文献   

    

M. Tanaka  Y. Minai  T. Watanabe  T. Tominaga 《Journal of Radioanalytical and Nuclear Chemistry》1992,164(4):255-264

Phthalocyanineiron(II) (FePc) and phthalocyaninato[(2-)bispyridine]iron(II) (FePc(py)₂) synthesized in supercage of NaY, KY and RbY zeolite have been characterized by Mössbauer and ESR spectroscopy. The yield of formation of the pyridine adduct depends on the ionic radius of the alkali ions introduced into the supercage, but not on the number of iron ions trapped in the cages, suggesting that free space in the supercage was the most important factor for the formation of the FePc-py-adducts.  相似文献   

    

Aoki S  Ye Y  Higuchi K  Takashima A  Tanaka Y  Kitagawa I  Kobayashi M 《Chemical & pharmaceutical bulletin》2001,49(10):1372-1374

Two novel aplysinopsin-type indole alkaloids, 1 and 2, and three known indole alkaloids were isolated from the marine sponge Hyrtios erecta. These compounds exhibited selective inhibitory activity against the neuronal isozyme of nitric oxide synthase (nNOS). Furthermore, new quinolone 7 was also isolated from the same marine sponge. The chemical structures of these new compounds were elucidated on the basis of spectroscopic analysis.  相似文献