著者

梅山 秀明

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.27, no.12, pp.3180-3182, 1979-12-25 (Released:2008-03-31)

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Closed shell LCAO-SCF-MO calculations were carried out for the chloride anion cryptate, which is of interest in connection with organic anion receptors and carriers. In the Cl- cryptate of [(C9H18)3(NH)2Cl]+Cl-, Cl- is encapsulated in the host molecule. Since the positions of the two protons bonded to the two nitrogens of the host molecule were not determined in the reported X-ray diffraction analyses, the positions of the two protons in the inclusion complex were decided by calculation using the ab initio molecular orbital method. A structure N+-H…Cl-…H-N+ in which Cl- is in between the two nitrogens was most stable at values of γ(NN) less than 7.0 Å. The structure N+-H…Cl-…H-N+ was most stable at γ(NN)=6.023 Å. In the most stable structure, the two protons are covalently bonded to the two nitrogens. The structure obtained by geometry optimization for the two ammonium ions and Cl- was similar to that determined by X-ray diffraction analysis.

著者

赤羽 健司 永野 泰夫 梅山 秀明

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.37, no.1, pp.86-92, 1989-01-25 (Released:2008-03-31)

参考文献数

26

被引用文献数

4 8

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Two empirical indices accounting for the hydrophobic interaction are described. The first index is a "hydrophobic field-effect (Hf) index, "which indicates the hydrophobic nature of the binding site of a host molecule such as an enzyme, and the second index is a "hydrophobic correlation (Hc) index", which indicates the hydrophobic correspondency between a host molecule and its guest molecule such as a ligand. Furthermore, a method to calculate the surface area of a molecule is described, in which the molecular surface is treated as a set of area-preserving spherical triangles. The hydrophobic effects on the interaction between papain and its inhibitor benzyloxycarbonyl-L-phenylalanyl-L-alanyl-methylene (Z-Phe-Ala-CH2-), which is covalently bound to catalytic Cys Sγ of the enzyme, were investigated by using these indices. It is quantitatively shown that the binding sites interacting with the benzene rings of P2 Phe and P3 Z are more hydrophobic, while the site of the carbonyl group of P1 Ala is more hydrophilic. The substrate specificity of papain can be explained in part by these indices. Both the Hc and Hf indices are visualized by using computer graphics. These indices would be useful as quantitative structure-activity relationship (QSAR) parameters.

著者

赤羽 健司 上條 哲聖 飯塚 欣二 田口 武夫 小林 義郎 木曽 良明 梅山 秀明

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.36, no.9, pp.3447-3452, 1988-09-25 (Released:2008-03-31)

参考文献数

31

被引用文献数

3 4

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The structure-activity relationship of acyl-His-trifluorinated leucinol derivatives as inhibitors of human renal renin is discussed based upon the tertiary structure of human renin, which was deduced from the crystal structure of penicillopepsin by assuming structural similarity. The structural requirements for the inhibitors and possible interactions at the renin binding site are discussed.

著者

飯塚 欣二 上條 哲聖 原田 弘 赤羽 健司 久保田 哲弘 島岡 巌 梅山 秀明 木曽 良明

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.36, no.6, pp.2278-2281, 1988-06-25 (Released:2008-03-31)

参考文献数

11

被引用文献数

4 4

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New human renin inhibitors were designed from transition-state analogues of angiotensinogen, synthesized and evaluated. The peptide derovative, which contained 1-naphthylmethylsuccinylamide residue (P3) with a retro-inverso amide bond and a norstatine isoamylamide residue (P1-P1'), was stable to proteases and had potent human renin inhibitory activity. This compact inhibitor exhibited hypotension when administered orally to a monkey.

著者

飯塚 欣二 上條 哲聖 原田 弘 赤羽 健司 久保田 哲弘 江藤 裕夫 島岡 厳 椿 敦 村上 真 山口 敏章 伊與部 亮 梅山 秀明 木曽 良明

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.38, no.9, pp.2487-2493, 1990-09-25 (Released:2008-03-31)

参考文献数

33

被引用文献数

7 11

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The synthesis and the structure-activity relationships of renin inhibitors designed from the angiotensinogen transition state are described. These inhibitors contained residues modified at P1-P1, , P2, and P4-P3. Decrease in the size of side chain alkyl group in norstatine analog at P1 diminished the inhibitory activities of the compounds. Compound 5j, which contained valine residue instead of histidine residue at P2, inhibited potently cathepsin D (IC50=6.0×10-9 M) and pepsin (IC50=3.5×10-7 M) to the same extent as renin (IC50=8.5×10-10 M), and thus was not specific for renin. The reduction of the β-carbonyl group to methylene group in β-carbonylpropionyl residue at P4-P3 decreased the potency about 2 orders against human renin (5i : IC50=1.1×10-7 M vs. 1 : IC50=2.4 ×10-9 M). These results confirmed the rationality of our analysis of the interaction between an orally potent human renin inhibitor 1 and the active site of human renin using modeling techniques, showing that 1 fits the active site of renin favorably. The experimental details of the synthesis are presented.

著者

梅山 秀明 工藤 貴子

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.29, no.2, pp.554-558, 1981-02-25 (Released:2008-03-31)

参考文献数

26

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Diborane as a molecular complex was studied by using a double zeta ab initio MO method and energy decomposition analyses. For diborane, a qualitatively major contribution of HOMO-LUMO transfers was reported by Yamabe et al. on the basis of configuration analyses by using a single zeta basis set. However, no quantitative work on the origin on the complex formation has been reported. In this note, we show that the charge transfer energy is the dominant contributor to the complex formation (2BH3→B2H6). The charge transfer energy and the exchange repulsion are analyzed at the molecular orbital (MO) levels.

著者

梅山 秀明 工藤 貴子 中川 節子

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.29, no.2, pp.287-292, 1981-02-25 (Released:2008-03-31)

参考文献数

32

被引用文献数

7 10

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The heat of complex formation of H3PBH3 was calculated to be -15.3 kcal/mol by double zeta ab initio LCAO MO SCF calculations ; this is very similar to the experimental values for (CH3)3PB(CH3)3 and (CH3)3PBF3. The origin of complex formation of H3PBH3 was elucidated by energy decomposition methods. The order of contributions is ES-(41%)>CT (37%)> PL (22%). The d atomic orbitals on phosphorus play a role in increasing the polarization energy upon complex formation. The barrier to internal rotation of H3PBH3 was calculated to be 2.4 kcal/mol, which is in very good agreement with the experimental value of 2.47kcal/mol. The exchange repulsion and the charge transfer energy related to the staggered form contribute to the barrier to internal rotation. The change of the charge transfer energy corresponds to the difference of the barrier heights between H3PBH3 and H3SiCH3. The energies of complex formation of F3PBH3 and (CH3)3PBH3 were calculated, to investigate the origin of the barrier to internal rotation.