KINDAI UNIVERSITY


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TANABE Genzoh

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FacultyDepartment of Pharmacy / Graduate School of Medicine / Pharmaceutical Research and Technology Institute
PositionProfessor
Degree
Commentator Guidehttps://www.kindai.ac.jp/meikan/354-tanabe-genzou.html
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Last Updated :2020/08/10

Research Activities

Research Areas

  • Life sciences, Pharmaceuticals - chemistry and drug development

Research Interests

  • α-glucosidase, salacia, kotalanol, salacinol

Published Papers

  • Synthesis of thiazinoimidazoles by lewis acid-catalyzed [3+3] cycloaddition reactions of propargyl alcohols with 2-mercaptoimidazoles, N. Mishima, T. Ogawa, G. Tanabe, O. Muraoka, H. Wasada, N. Hatae, M. Yoshimatsu, 3117 - 3121, May 2019 , Refereed
  • An engineered aryl acid adenylation domain with an enlarged substrate binding pocket, TANABE Genzoh, Angew. Chem. Int. Ed., Angew. Chem. Int. Ed., 58, 6906 - 6910, May 2019 , Refereed
  • Facile synthesis of neokotalanol, a potent α-glycosidase inhibitor isolated from the Ayurvedic traditional medicine “Salacia”., G. Tanabe, S. Ueda, K. Kurimoto, N. Sonoda, S. Marumoto, F. Ishikawa, W. Xie, O. Muraoka, ACS Omega, ACS Omega, 4, 7533 - 7533, Apr. 2019 , Refereed
  • Design, synthesis and biological evaluation of nitrate derivatives of sauropunol A and B as potent vasodilatory agents, L. Lu, X. Rao, R. Cong, C. Zhang, Z. Wang, J. Xu, G. Tanabe, O. Muraoka, X. Wu, W. Xie, Molecules, Molecules, 24, 583, Feb. 2019 , Refereed
  • Practical route to neokotalanol and its natural analogues: sulfonium sugars with antidiabetic activities., Y. Huang, Y. Gao, W. He, Z. Wang, W. Li, Z. Wang, W. Li, A. Lin, G. Tanabe, O. Muraoka, X. Wu, W. Xie, Angew. Chem. Int. Ed., Angew. Chem. Int. Ed., 58, 6400 - 6404, Feb. 2019 , Refereed
  • Unprecedented nucleophile-promoted 1,7-S or Se shift reactions under Pummerer reaction conditions of 4-alkenyl-3-sulfinylmethylpyrroles, T. Go, A. Morimatsu, H. Wasada, G. Tanabe, O. Muraoka, Y. Sawada, M. Yoshimatsu, Beilstein J. Org. Chem., Beilstein J. Org. Chem., 14, 2722 - 2729, Oct. 2018 , Refereed
  • Synthesis of salacinol-d4 as an internal standard for mass-spectrometric quantitation of salacinol, a potent a-glucosidase inhibitor found in a traditional Ayurvedic medicine “Salacia”, G. Tanabe, S. Teramae, Y.e Kunikata, S. Marumoto, S. Okugawa, F. Ishikawa, W. Xie, T. Morikawa, O. Muraoka, Heterocycles, Heterocycles, 97, 314 - 332, Sep. 2018 , Refereed
  • Expanding the Scope of Functionalized Small Nonprotein Components for Holoabzyme 27C1, F. Ishikawa, M. Shirahashi, H. Hayakawa, G. Tanabe, T. Tsumuraya, I. Fujii, ChemistrySelect, ChemistrySelect, 3, 9313 - 9317, Aug. 2018 , Refereed
  • Total synthesis of γ-alkylidenebutenolides, potent melanogenesis inhibitors from Thai medicinal plant Melodorum fruticosum, G. Tanabe, Y. Manse, T. Ogawa, N. Sonoda, S. Marumoto, F. Ishikawa, K. Ninomiya, S. Chaipech, Y. Pongpiriyadacha, O. Muraoka, T. Morikawa, J. Org. Chem., J. Org. Chem., 83, 8250 - 8261, Jul. 2018 , Refereed
  • First total synthesis of cyclic pentadepsipeptides Hikiamides A–C, D. Fu, X. Rao, J. Xu, G. Tanabe, O. Muraoka, X. Wu, W Xie, Tetrahedron Lett., Tetrahedron Lett., 59, 2876 - 2879, Jul. 2018 , Refereed
  • Structural basis of protein−protein interactions between a trans-acting acyltransferase and acyl carrier protein in polyketide disorazole biosynthesis, A. Miyanaga, R. Ouchi, F. Ishikawa, E. Goto, G. Tanabe, F. Kudo, T. Eguchi, J. Am. Chem. Soc., J. Am. Chem. Soc., 140, 7970 - 7978, Jun. 2018 , Refereed
  • First total syntheses of Amorfrutin C and pseudo-Amorfrutin A, Q. Miao, Y. Li, J. Xu, A. Lin, G. Tanabe, O. Muraoka, X. Wu, W. Xie, Eur. J. Org. Chem., Eur. J. Org. Chem., 1443 - 1448, Mar. 2018 , Refereed
  • Diastereoselective synthesis of salacinol-type α-glucosidase inhibitors, F. Ishikawa, K. Jinno, E. Kinouchi, K. Ninomiya, S. Marumoto, W. Xie, O. Muraoka, T. Morikawa, G. Tanabe, J. Org. Chem., J. Org. Chem., 83, 185 - 193, Jan. 2018 , Refereed
  • A Chemoproteomics Approach to Investigate Phosphopantetheine Transferase Activity at the Cellular Level, S. Konno, F. Ishikawa, T. Suzuki, N. Dohmae, H. Kakeya, G. Tanabe, ChemBioChem, ChemBioChem, 18, 2199 - 2204, Sep. 2017 , Refereed
  • Computational study on the comparative differences in the activity of inhibitors of human versus rat alpha-glucosidase, TANABE Genzoh, Open Journal of Medicinal Chemistry, Open Journal of Medicinal Chemistry, 7(2), 19 - 28, Jun. 2017 , Refereed
  • In Vitro Regio- and Stereoselective Oxidation of beta-Ionone by Human Liver Microsomes, Shinsuke Marumoto, Ryoyu Shimizu, Genzoh Tanabe, Yoshiharu Okuno, Mitsuo Miyazawa, PLANTA MEDICA, PLANTA MEDICA, 83(3-4), 292 - 299, Feb. 2017 , Refereed
    Summary:The metabolism of the norisoprenoid beta-ionone was investigated in vitro using human liver microsomes and 11 different recombinant cytochrome P450 enzymes expressed in Trichoplusia ni cells. beta-Ionone was found to be oxidized via 4S-hydroxylation by CYP2B6 in human liver microsomes. CYP1A2 also regioselectively catalyzed the hydroxylation of beta-ionone to yield 4-hydroxylation; this conversion was not stereoselective. Further kinetic analysis revealed that CYP2B6 exhibited the highest activity for beta-ionone 4-hydroxylation. Kinetic analysis showed that K-m and V-max for oxidation of beta-ionone by CYP1A2 and CYP2B6 was 107.9 +/- 36.0 mu M and 3200.3 +/- 323.0 nmol/min/nmol P450 and 5.6 +/- 1.2 mu M and 572.8 +/- 29.8 nmol/min/nmol P450, respectively. The reaction rates observed using human liver microsomes and recombinant CYP2B6 were very high compared with those of other CYP2B6 substrates reported thus far. These results suggest that beta-ionone, a norisoprenoid present in nature, is one of the effective substrates for CYP2B enzymes in human liver microsomes. To the best of our knowledge, this is the first time that 4-hydroxy beta-ionone has been described as a human metabolite of beta-ionone.
  • Structure-activity relationship studies on acremomannolipin A, the potent calcium signal modulator with a novel glycolipid structure 4: Role of acyl side chains on D-mannose, Nozomi Tsutsui, Genzoh Tanabe, Nami Ikeda, Saika Okamura, Marika Ogawa, Kuniko Miyazaki, Ayako Kita, Reiko Sugiura, Osamu Muraoka, EUROPEAN JOURNAL OF MEDICINAL CHEMISTRY, EUROPEAN JOURNAL OF MEDICINAL CHEMISTRY, 121, 250 - 271, Oct. 2016 , Refereed
    Summary:As part of an ongoing study on the structure-activity relationship of acremomannolipin A (1)-the novel glycolipid isolated from Acremonium strictum possessing potent calcium signal-modulating activity-the role of acyl substituents on the D-mannose moiety was examined. Three partially deacylated homologs (2a-2c) and 20 homologs (2d-2w) bearing different acyloxy side chains were synthesized via the stereoselective beta-mannosylation of appropriately protected mannosyl sulfoxides (3) with D-mannitol derivatives (4), and their calcium signal-modulating activities were examined. The activities of 2a-2c were completely lost. Homologs bearing relatively short acyloxy groups at C-3, C-4, and C-6 positions (2t-2v) exhibited less activity than 1, whereas a heptanoyl homolog (2w: C-7) maintained activity nearly equal to that of 1. When the acyl groups at these three positions were substituted by an octanoyl group (2i: C-8), the activity was completely lost. On the other hand, of the 10 homologs in which the octanoyl at C-2 was substituted by other acyloxy moieties (2j-2s), three (2m: C-7, 2n: C-9, 2o: C-10) maintained potent activity. These results suggested that peracylated mannose structure is critical for calcium signal modulating activity, and this activity is precisely dependent on the length of four acyl side chains on D-mannose. (C) 2016 Published by Elsevier Masson SAS.
  • Hydrophobic substituents increase the potency of salacinol, a potent alpha-glucosidase inhibitor from Ayurvedic traditional medicine 'Salacia', Genzoh Tanabe, Weijia Xie, Gorre Balakishan, Mumen F. A. Amer, Nozomi Tsutsui, Haruka Takemura, Shinya Nakamura, Junji Akaki, Kiyofumi Ninomiya, Toshio Morikawa, Isao Nakanishi, Osamu Muraoka, BIOORGANIC & MEDICINAL CHEMISTRY, BIOORGANIC & MEDICINAL CHEMISTRY, 24(16), 3705 - 3715, Aug. 2016 , Refereed
    Summary:Using an in silico method, seven analogs bearing hydrophobic substituents (8a: Me, 8b: Et, 8c: n-Pent, 8d: n-Hept, 8e: n-Tridec, 8f: isoBu and 8g: neoPent) at the 3'-O-position in salacinol (1), a highly potent natural alpha-glucosidase inhibitor from Ayurvedic traditional medicine 'Salacia', were designed and synthesized. In order to verify the computational SAR assessments, their alpha-glucosidase inhibitory activities were evaluated in vitro. All analogs (8a-8g) exhibited an equal or considerably higher level of inhibitory activity against rat small intestinal alpha-glucosidases compared with the original sulfonate (1), and were as potent as or higher in potency than the clinically used anti-diabetics, voglibose, acarbose or miglitol. Their activities against human maltase exhibited good relationships to the results obtained with enzymes of rat origin. Among the designed compounds, the one with a 3'-O-neopentyl moiety (8g) was most potent, with an approximately ten fold increase in activity against human maltase compared to 1. (C) 2016 Elsevier Ltd. All rights reserved.
  • Mangiferin enhances the sensitivity of human multiple myeloma cells to anticancer drugs through suppression of the nuclear factor κB pathway., Tomoya Takeda, Masanobu Tsubaki, Toshiki Kino, Ayako Kawamura, Shota Isoyama, Tatsuki Itoh, Motohiro Imano, Genzoh Tanabe, Osamu Muraoka, Hideaki Matsuda, Takao Satou, Shozo Nishida, International journal of oncology, International journal of oncology, 48(6), 2704 - 12, Jun. 2016 , Refereed
    Summary:Multiple myeloma (MM) is still an incurable hematological malignancy with a 5-year survival rate of ~35%, despite the use of various treatment options. The nuclear factor κB (NF-κB) pathway plays a crucial role in the pathogenesis of MM. Thus, inhibition of the NF-κB pathway is a potential target for the treatment of MM. In a previous study, we showed that mangiferin suppressed the nuclear translocation of NF-κB. However, the treatment of MM involves a combination of two or three drugs. In this study, we examined the effect of the combination of mangiferin and conventional anticancer drugs in an MM cell line. We showed that the combination of mangiferin and an anticancer drug decreased the viability of MM cell lines in comparison with each drug used separately. The decrease in the combination of mangiferin and an anticancer drug induced cell viability was attributed to increase the expression of p53 and Noxa and decreases the expression of XIAP, survivin, and Bcl-xL proteins via inhibition of NF-κB pathway. In addition, the combination treatment caused the induction of apoptosis, activation of caspase-3 and the accumulation of the cells in the sub-G1 phase of the cell cycle. Our findings suggest that the combination of mangiferin and an anticancer drug could be used as a new regime for the treatment of MM.
  • Highly Diastereoselective Route to alpha-Glucosidase Inhibitors, Neosalacinol and Neoponkoranol, Genzoh Tanabe, Youya Matsuda, Misato Oka, Yousuke Kunikata, Nozomi Tsutsui, Weija Xie, Gorre Balakishan, Mumen F. A. Amer, Shinsuke Marumoto, Osamu Muraoka, JOURNAL OF ORGANIC CHEMISTRY, JOURNAL OF ORGANIC CHEMISTRY, 81(8), 3407 - 3415, Apr. 2016 , Refereed
    Summary:A facile and highly diastereoselective route to potent natural a-glucosidase inhibitors, i.e., neosalacinol (4) and neoponkoranol (6), isolated from the traditional Ayurvedic medicine "Salacia" was developed by intramolecular cyclization of appropriately substituted sulfides (9 and 12).
  • Design, synthesis and biological evaluation of 3 '-benzylated analogs of 3 '-epi-neoponkoranol as potent alpha-glucosidase inhibitors, Dan Liu, Weigang He, Zihao Wang, Long Liu, Chengqian Wang, Chenxi Zhang, Chengcheng Wang, Yuxuan Wang, Genzoh Tanabe, Osamu Muraoka, Xiaoming Wu, Liang Wu, Weijia Xie, EUROPEAN JOURNAL OF MEDICINAL CHEMISTRY, EUROPEAN JOURNAL OF MEDICINAL CHEMISTRY, 110, 224 - 236, Mar. 2016 , Refereed
    Summary:A group of 3'-epi-neoponkoranol analogs with different hydrophobic substituents attached at 3'-position of side chain moiety were designed and synthesized in order to further improve the inhibitory activities against alpha-glucosidases. Biological evaluation of these compounds revealed that sulfonium salts attached with ortho-substituted benzyl groups showed best alpha-glucosidase inhibitory activities. The most potent compound 10i showed greater inhibitory activities than all natural products. Moreover, docking studies on 10i with ntMGAM presented a new binding mode, indicating that amino residue Asp542 should be the key interacting point for strong inhibitory activity of small molecules against alpha-glucosidase enzymes. The strongest alpha-glucosidase inhibitory activity of 10i could be rationalized by van der Waals interactions between the 3'-attached substituent and particularly the ortho-substituted trifluoromethyl on benzyl group with the adjacent hydrophobic amino residues. Cytotoxicity evaluation assay demonstrated a high level of safety profile of the synthesized sulfonium salts against normal cell line. The enzyme kinetic studies showed a fully competitive inhibition of these sulfonium salts on each alpha-glucosidase. (C) 2016 Elsevier Masson SAS. All rights reserved.
  • Total Synthesis of 4,5-Didehydroguadiscine: A Potent Melanogenesis Inhibitor from the Brazilian Medicinal Herb, Hornschuchia obliqua., Tanabe G, Sugano Y, Shirato M, Sonoda N, Tsutsui N, Morikawa T, Ninomiya K, Yoshikawa M, Muraoka O, Journal of Natural Products, Journal of Natural Products, 78(7), 1542, Aug. 2015 , Refereed
  • Mangiferin suppresses CIA by suppressing the expression of TNF-α, IL-6, IL-1β, and RANKL through inhibiting the activation of NF-κB and ERK1/2, M. Tsubaki, T. Takeda, T. Kino, T. Itoh, M. Imano, G. Tanabe, O. Muraoka, T. Satou, S. Nishida, Am. J. Transl. Res., Am. J. Transl. Res., 7, 1371 - 1381, Jul. 2015 , Refereed
  • Evaluation of Salacia Species as Anti-diabetic Natural Resources Based on Quantitative Analysis of Eight Sulphonium Constituents: A New Class of alpha-Glucosidase Inhibitors, Junji Akaki, Toshio Morikawa, Sohachiro Miyake, Kiyofumi Ninomiya, Mayumi Okada, Genzoh Tanabe, Yutana Pongpiriyadacha, Masayuki Yoshikawa, Osamu Muraoka, PHYTOCHEMICAL ANALYSIS, PHYTOCHEMICAL ANALYSIS, 25(6), 544 - 550, Nov. 2014 , Refereed
    Summary:IntroductionStems and roots of Salacia genus plants have been used in Ayurveda as a specific remedy for early stage diabetes. Previous investigations identified four sulphonium sulphates, that is, salacinol (1), kotalanol (3), ponkoranol (5) and salaprinol (7), as the compounds responsible for the anti-diabetic activity. Their desulphonates (2, 4, 6 and 8) were also isolated as active constituents. Two separate quantitative analytical protocols, that is, for 1 and 3 and for 2 and 4, have been developed recently. ObjectiveTo: validate the two analytical protocols with respect to all eight sulphoniums; evaluate the quality of a variety of Salacia samples collected in different geographical regions, that is, Thailand, Sri Lanka and India; and determine their distribution in each part of the plant, that is, stems/roots, leaves and fruits. MethodsAnalyses of four sulphonium sulphates in 32 Salacia extracts were carried out on an Asahipak NH2P-50 column, and those of the corresponding desulphonates were conducted on an Inertsil ODS-3 column. ResultsNeokotalanol (4) was the major constituent in Salacia samples from Thailand, whereas 1 was the primary constituent in extracts of the stems/roots of plants from Sri Lanka and India. These sulphoniums were only present in trace amounts in leaves and fruits of the plants. ConclusionTwo analytical protocols were successfully applied to analyse 32 Salacia samples, and revealed that sulphoniums (1-8) had characteristic distributions due to the plant part and/or due to geographical region. Copyright (c) 2014 John Wiley & Sons, Ltd. Using the recently developed two analytical protocols, the distributions of eight sulphoniums (1-8) responsible for the anti-diabetic activity of Salacia, a specific remedy for the treatment of early stage diabetes in Ayurveda, were examined in 32 extracts of Salacia samples collected in Thailand, Sri Lanka and India. The distribution of these sulphoniums in the different plant parts was also examined. Each constituent had characteristic distributions in the different plant parts and different geographical regions.
  • Synthetic study on neoponkoranol and its side chain epimer as potent alpha-glucosidase inhibitors, optimization of protecting group, Dan Liu, Weijia Xie, Long Liu, Hequan Yao, Jinyi Xu, Genzoh Tanabe, Osamu Muraoka, Xiaoming Wu, TETRAHEDRON LETTERS, TETRAHEDRON LETTERS, 54(47), 6333 - 6336, Nov. 2013 , Refereed
    Summary:Coupling reaction between thiosugar and triflate as the key protocol to synthesize neoponkoranol, a naturally occurring potent alpha-glucosidase inhibitor, and its related sulfonium salts was optimized by applying different esters as protecting group, with the yields of desired products being greatly improved. Our proposed mechanism of the coupling reaction indicated that the nucleophilicity of C3-hydroxyl moiety on monosaccharide structure is closely related to the reaction mode. (C) 2013 Elsevier Ltd. All rights reserved.
  • Total synthesis of neokotalanol, a potent α-glucosidase inhibitor isolated from Salacia reticulata., Xie WJ, Tanabe G, Tsutsui N, Wu XM, Muraoka O, Chinese journal of natural medicines, Chinese journal of natural medicines, 11(6), 676 - 683, Nov. 2013 , Refereed
  • Chemistry of propargyl compounds activated by sulfur functional groups–development of methodology for the synthesis of Heterocycles triggered by functionalizations, M. Yoshimatsu, G. Tanabe, O. Muraoka, Yuki Gousei Kagaku kyokai shi, Yuki Gousei Kagaku kyokai shi, 71, 1282 - 1293, Jan. 2013 , Refereed
  • Research progress of synthesis and structure-activity relationship studies on sulfonium-type α-glucosidase inhibitors isolated from Salacia genus plants, W. Xie, G. Tanabe, J. Xu, X. Wu, T. Morikawa, M. Yoshikawa, O. Muraoka, Mini-Rev. Org. Chem., Mini-Rev. Org. Chem., 10, 141 - 159, Jan. 2013 , Refereed
  • Role of the side chain stereochemistry in the alpha-glucosidase inhibitory activity of kotalanol, a potent natural alpha-glucosidase inhibitor. Part 2, Genzoh Tanabe, Kanjyun Matsuoka, Masahiro Yoshinaga, Weijia Xie, Nozomi Tsutsui, Mumen F. A. Amer, Shinya Nakamura, Isao Nakanishi, Xiaoming Wu, Masayuki Yoshikawa, Osamu Muraoka, BIOORGANIC & MEDICINAL CHEMISTRY, BIOORGANIC & MEDICINAL CHEMISTRY, 20(21), 6321 - 6334, Nov. 2012 , Refereed
    Summary:To examine the role of the side chain of kotalanol (2), a potent natural alpha-glucosidase inhibitor isolated from Salacia reticulata, on inhibitory activity, four diastereomers (11a-11d) with reversed configuration (S) at the C-4' position in the side chain were synthesized and evaluated. Two of the four (11b and 11d) significantly lost their inhibitory activity against both maltase and sucrase, while the other two (11a and 11c) sustained the inhibitory activity to a considerable extent, showing distinct activity in response to the change of stereochemistry of the hydroxyls at the 5' and 6' positions. Different activities were rationalized with reference to in silico docking studies on these inhibitors with hNtMGAM. Against isomaltase, all four analogs showed potent inhibitory activity as well as 2, and 11b and 11d exhibited enzyme selectivity. (C) 2012 Elsevier Ltd. All rights reserved.
  • Homology modeling of human alpha-glucosidase catalytic domains and SAR study of salacinol derivatives, S. Nakamura, K. Takahira, G. Tanabe, O. Muraoka, I. Nakanishi, Open J. Med. Chem., Open J. Med. Chem., 2, 50 - 60, Sep. 2012 , Refereed
  • In silico design, synthesis and evaluation of 3 '-O-benzylated analogs of salacinol, a potent alpha-glucosidase inhibitor isolated from an Ayurvedic traditional medicine "Salacia", Genzoh Tanabe, Shinya Nakamura, Nozomi Tsutsui, Gorre Balakishan, Weijia Xie, Satoshi Tsuchiya, Junji Akaki, Toshio Morikawa, Kiyofumi Ninomiya, Isao Nakanishi, Masayuki Yoshikawa, Osamu Muraoka, CHEMICAL COMMUNICATIONS, CHEMICAL COMMUNICATIONS, 48(69), 8646 - 8648, 2012 , Refereed
    Summary:With the aid of an in silico method, alpha-glucosidase inhibitors with far more potent activities than salacinol (1), a potent natural alpha-glucosidase inhibitor isolated from an Ayurvedic traditional medicine Salacia reticulata, have been developed.
  • Biological evaluation of 3 '-O-alkylated analogs of salacinol, the role of hydrophobic alkyl group at 3 ' position in the side chain on the alpha-glucosidase inhibitory activity, Genzoh Tanabe, Tetsu Otani, Wenying Cong, Toshie Minematsu, Kiyofumi Ninomiya, Masayuki Yoshikawa, Osamu Muraoka, BIOORGANIC & MEDICINAL CHEMISTRY LETTERS, BIOORGANIC & MEDICINAL CHEMISTRY LETTERS, 21(10), 3159 - 3162, May 2011 , Refereed
    Summary:Four analogs with 3'-O-alkyl groups (9a: CH(3), 9b: C(2)H(5), 9c: C(13)H(27) or 9d: CH(2)Ph) instead of the 3'-O-sulfate anion in salacinol (1), a naturally occurring potent alpha-glucosidase inhibitor, were synthesized by the coupling reaction of 1,4-dideoxy-1,4-epithio-D-arabinitols (18a and 18b) with appropriate epoxides (10a-10d). These analogs showed equal or considerably higher inhibitory activity against rat small intestinal alpha-glucosidases than the original sulfate (1), and one of them (9d) was found more potent than currently used alpha-glucosidase inhibitors as antidiabetics. Thus, introduction of a hydrophobic moiety at the C3' position of this new class of inhibitor was found beneficial for onset of stronger inhibition against these enzymes. (C) 2011 Elsevier Ltd. All rights reserved.
  • Role of the side chain stereochemistry in the alpha-glucosidase inhibitory activity of kotalanol, a potent natural alpha-glucosidase inhibitor, Weijia Xie, Genzoh Tanabe, Kanjyun Matsuoka, Mumen F. A. Amer, Toshie Minematsu, Xiaoming Wu, Masayuki Yoshikawa, Osamu Muraoka, BIOORGANIC & MEDICINAL CHEMISTRY, BIOORGANIC & MEDICINAL CHEMISTRY, 19(7), 2252 - 2262, Apr. 2011 , Refereed
    Summary:Synthesis and evaluation of four diastereomers (9a, 9b, 9c and 9d) of kotalanol, a potent alpha-glucosidase inhibitor isolated from an Ayurvedic medicinal plant Salacia species, are described. Stereo-inversion at C-3' and C-4' of kotalanol (2) caused significant decrease of the inhibitory activities against maltase and sucrase, whereas inhibitory activity against isomaltase sustained, thus resulted in exerting selectivity against isomaltase. (C) 2011 Elsevier Ltd. All rights reserved.
  • Isolation, structure identification and SAR studies on thiosugar sulfonium salts, neosalaprinol and neoponkoranol, as potent alpha-glucosidase inhibitors, Weijia Xie, Genzoh Tanabe, Junji Akaki, Toshio Morikawa, Kiyofumi Ninomiya, Toshie Minematsu, Masayuki Yoshikawa, Xiaoming Wu, Osamu Muraoka, BIOORGANIC & MEDICINAL CHEMISTRY, BIOORGANIC & MEDICINAL CHEMISTRY, 19(6), 2015 - 2022, Mar. 2011 , Refereed
    Summary:Two hitherto missing members of sulfonium salts family in Salacia genus plants as a new class of a-glucosidase inhibitors, neoponkoranol (7) and neosalaprinol (8), were isolated from the water extracts, and their structures were unambiguously identified. For further SAR studies on this series of sulfonium salts, several epimers of 7 and 8 were synthesized, and their inhibitory activities against rat small intestinal alpha-glucosidases were evaluated. Among them, 3'-epimer of 7 was found most potent in this class of molecules, and revealed as potent as currently used antidiabetics, voglibose and acarbose. (C) 2011 Elsevier Ltd. All rights reserved.
  • Docking and SAR studies of salacinol derivatives as alpha-glucosidase inhibitors, Shinya Nakamura, Kazunori Takahira, Genzoh Tanabe, Toshio Morikawa, Mika Sakano, Kiyofumi Ninomiya, Masayuki Yoshikawa, Osamu Muraoka, Isao Nakanishi, BIOORGANIC & MEDICINAL CHEMISTRY LETTERS, BIOORGANIC & MEDICINAL CHEMISTRY LETTERS, 20(15), 4420 - 4423, Aug. 2010 , Refereed
    Summary:Salacinol is a potent alpha-glucosidase inhibitor isolated from Salacia reticulata, and a good lead compound for an antidiabetic drug. It is essential to clarify the binding state of salacinol to alpha-glucosidase for efficient optimization study using structure-based drug design. Redocking simulations of two inhibitors, acarbose and casuarine whose complex structures are known, were performed to assure the appropriate docking pose prediction. The simulation reproduced both experimental binding states with accuracy. Then, using the same simulation protocol, the binding mode of salacinol and its derivatives has been predicted. Salacinol bound to the protein with a similar binding mode as casuarine, and the predicted structures could explain most of the structure-activity relationships of salacinol derivatives. (C) 2010 Elsevier Ltd. All rights reserved.
  • alpha-Sulfanyl and alpha-Selanyl Propadienyl Cations: Regioselective Generations and Cycloadditions with Thioamides and Selemides Controlled by MeNO2-H2O System, Mitsuhiro Yoshimatsu, Teruhisa Yamamoto, Arisa Sawa, Tomohiro Kato, Genzoh Tanabe, Osamu Muraoka, ORGANIC LETTERS, ORGANIC LETTERS, 11(13), 2952 - 2955, Jul. 2009 , Refereed
    Summary:alpha-Sultanyl and alpha-selanyl propadienyl cations were easily generated by the catalytic system, scandium triflate-nitromethane-H2O in the presence of Bu4NHSO4, to regioselectively afford the multifunctionalized thiazoles and selenazoles in high yields.
  • An alternative synthesis of de-O-sulfated salacinol and structure revision of neosalacinol, an α-glucosidase inhibitor, G. Tanabe, W. Xie, A. Ogawa, T. Minematsu, M. Yoshikawa, O. Muraoka, Bioorg. Med. Chem. Lett., Bioorg. Med. Chem. Lett., 19(8), 2195 - 2198, Apr. 2009 , Refereed
  • SYNTHESES AND EVALUATION AS GLYCOSIDASE INHIBITOR OF 1,5-DIDEOXY-1,5-IMINO-D-GLUCITOL ANALOGS OF SALACINOL, A POTENT alpha-GLUCOSIDASE INHIBITOR ISOLATED FROM AYURVEDIC MEDICINE, SALACIA RETICULATA, Genzoh Tanabe, Takanori Hatanaka, Toshie Minematsu, Hisashi Matsuda, Masayuki Yoshikawa, Osamu Muraoka, HETEROCYCLES, HETEROCYCLES, 79, 1093 - 1100, Apr. 2009 , Refereed
    Summary:N-Alkylated deoxynojirimycin (10) bearing the same alkyl chain as salacinol (1), a potent alpha-glucosidase inhibitor isolated from Ayurvedic traditional medicine, Salacia reticulata, was found to inhibit both rat intestinal maltase and sucrase as strong as 1, while 10 has been reported to be inactive against glucoamylase G2 from Aspergillus niger. Its O-desulfate (12) was also found active against these enzymes, and characteristic sulfate anion moiety of I was found not essential for the alpha-glucosidase inhibitory activity.
  • Salaprinol and ponkoranol with thiosugar sulfonium sulfate structure from Slacia prinoides and α-glucosidase inhibitory activity of ponkoranol and kotalanol desulfate, M. Yoshikawa, F. Xu, S. Nakamura, T. Wang, H. Matsuda, G. Tanabe, O. Muraoka, Heterocycles, Heterocycles, 75(6), 1397 - 1405, Jan. 2008 , Refereed
  • Total synthesis of (+/-)-stemonamide and (+/-)-isostemonamide using a radical cascade, Tsuyoshi Taniguchi, Genzo Tanabe, Osamu Muraoka, Hiroyuki Ishibashi, ORGANIC LETTERS, ORGANIC LETTERS, 10(2), 197 - 199, Jan. 2008 , Refereed
    Summary:Total synthesis of stemonamide and isostemonamide is described. The concise construction of the tricyclic core of these alkaloids was achieved by radical cascade involving 7-endo and 5-endo cyclizations.
  • Biological evaluation of de-O-sulfonated analogs of salacinol, the role of sulfate anion in the side chain on the α-glucosidase inhibitory activity, G. Tanabe, K. Yoshikai, T. Hatanaka, M. Yamamoto, Y. Shao, T. Minematsu, O. Muraoka, T. Wang, H. Matsuda, M.Yoshikawa, Bioorg. Med. Chem., Bioorg. Med. Chem., 15, 3296 - 3973, Jun. 2007 , Refereed
  • Structure-activity relationships of salacinol and kotalanol against α-glucosidae and evaluation of salacia extracts by LC-MS., Tanabe G, Matsuoka K, Minematsu T, Morikawa T, Ninomiya K, Matsuda H, Yoshikawa M, Murata H, Muraoka O, J. Pharm. Soc. Jpn., J. Pharm. Soc. Jpn., 127(Suppl.4), 129 - 130, 2007 , Refereed
  • Synthesis of a salacinol analogue and its α-glucosidase inhibitory activity., H. Kinoshita, T. Osamura, K. Mizuno, K. Kazumi, S. Kinoshita, T. Iwamura, S. Watanabe, T. Kataoka, O. Muraoka, G. Tanabe, Acta Pharm. Sinica, Acta Pharm. Sinica, 41, 647 - 653, Jul. 2006 , Refereed
  • Synthesis and biological evaluation of deoxy salacinols, the role of polar substituents in the side chain on the alpha-glucosidase inhibitory activity, O Muraoka, K Yoshikai, H Takahashi, T Minematsu, GX Lu, G Tanabe, T Wang, H Matsuda, M Yoshikawa, BIOORGANIC & MEDICINAL CHEMISTRY, BIOORGANIC & MEDICINAL CHEMISTRY, 14(2), 500 - 509, Jan. 2006 , Refereed
    Summary:Three analogs (5, 6, and 7) lacking polar substituents in the side chain of a naturally occurring a-glucosidase inhibitor, salacinol (la), were synthesized by the coupling reaction of a thiosugar, 1,4-dideoxy-1,4-epithio-D-arabinitol (3), with cyclic sulfates (8, 9, and 10), and their a-glucosidase inhibitory activities were examined. All these simpler analogs (5, 6, and 7) showed less inhibitory activity compared to la, and proved the importance of cooperative role of the polar substituents for the a-glucosidase inhibitory activity. A practical synthetic route to 3 starting from D-xylose is also described. (c) 2005 Elsevier Ltd. All rights reserved.
  • Design and synthesis of a simplified analogue of salacinol, Muraoka O, Tanabe G, Shao Y, Daxue Zhongguo Yaoke Daxue Xuebao, Daxue Zhongguo Yaoke Daxue Xuebao, 37, 403 - 406, 2006 , Refereed
  • Z-selective or stereospecific alkenylation reaction: A novel synthetic method for a-fluoro-a,b-unsaturated esters., M. Yoshimatsu, Y. Murase, A. Itoh, G. Tanabe, O. Muraoka, Chem. Lett., Chem. Lett., 34(7), 998 - 999, Jul. 2005 , Refereed
  • Antidiabetogenic constituents from Salacia species., H. Matsuda, M. Yoshikawa, T. Morikawa, G. Tanabe, O. Muraoka, J. Trad. Med., J. Trad. Med., 22(Suppl. 1), 145 - 153, Jun. 2005 , Refereed
  • Chalcogeno-Morita-Baylis-Hillman reaction of enones with acetals: Simple alpha-alkoxyalkylation of enones, H Kinoshita, T Osamura, S Kinoshita, T Iwamura, SI Watanabe, T Kataoka, G Tanabe, O Muraoka, JOURNAL OF ORGANIC CHEMISTRY, JOURNAL OF ORGANIC CHEMISTRY, 68(19), 7532 - 7534, Sep. 2003 , Refereed
    Summary:1-[2-(Methylsulfanyl)phenyl]prop-2-en-1-one (1) and the seleno congener (2) reacted with acetals 3 and 21 in the presence of (BF3Et2O)-Et-. to give alpha-alkoxyalkyl enones 4, 5 and 22, 23 in good yields. When the reaction mixtures were worked up with a saturated NaHCO3 solution instead of Et3N, onium salts 6 and 7 were obtained together with 4 and 5. Reactions with cyclic acetal 14 gave alpha-(beta-hydroxy-ethoxy) enones 15 and 16 accompanied by dimeric products 17 and 18.
  • Di-tert-butylsilylene (DTBS) group-directed alpha-selective galactosylation unaffected by C-2 participating functionalities, A Imamura, H Ando, S Korogi, G Tanabe, O Muraoka, H Ishida, M Kiso, TETRAHEDRON LETTERS, TETRAHEDRON LETTERS, 44(35), 6725 - 6728, Aug. 2003 , Refereed
    Summary:We have discovered an unusual alpha-galactosylation using phenylthioglycoside of 4,6-O-di-tert-butylsilylene (DTBS)-protected galactose derivatives as a glycosyl donor, which was not hampered by the neighboring participation of C-2 acyl functionality such as NTroc and OBz. The power of the DTBS effect has been exemplified by the coupling reaction with various glycosyl acceptors. (C) 2003 Elsevier Ltd. All rights reserved.
  • Absolute Stereostructure of Potent α-Glucosidase Inhibitor, Salacinol, with Unique Thiosugar Sulfonium Sulfate Inner Salt Structure from Salacia reticulata, M. Yoshikawa, T. Morikawa, H. Matsuda, G. Tanabe, O. Muraoka, Bioorg. Med. Chem., Bioorg. Med. Chem., 10(5), 1547 - 1554, May 2002 , Refereed
  • A Novel Push-Pull Diels-Alder Diene: Reactions of 4 Alkoxy- or 4-Phenylsulfenyl-5-chalcogene-Substituted l-Phenylpenta-2,4-dien-1-one with Electron-Deficient Dienophiles, M. Yoshimatsu, M. Hibino, M. Ishida, G. Tanabe, O. Muraoka, Chem. Pharm. Bull., Chem. Pharm. Bull., 50 (11), 1520 - 1524, 2002 , Refereed
  • Absolute stereostructures of novel norcadinane- and trinoreudesmane-type sesquiterpenes with nitric oxide production inhibitory activity from Alpinia oxyphylla, O. Muraoka, M. Fujimoto, G. Tanabe, M. Kubo, T. Minematsu, H. Matsuda, T. Morikawa, I. Toguchida, M. Yoshikawa, Bioorg. Med. Chem. Lett., Bioorg. Med. Chem. Lett., 11(16), 2217 - 2220, Aug. 2001 , Refereed
  • Synthesis and structure of 1-methyl-2,6-bis(electron-withdrawing group)-substituted selenabenzenes, E. Honda, T. Iwamura, S. Watanabe, T. Kataoka, O. Muraoka, G. Tanabe, J. Chem. Soc., Perkin Trans. 1, J. Chem. Soc., Perkin Trans. 1, (5), 529 - 536, Mar. 2001 , Refereed
  • A Concise Construction of an Erythrinane Skeleton Using Mn((]G0003[))/Cu((]G0002[))-mediated Oxidative Radical Cyclization of α-Methylthio Amides., A. Toyao, S. Chikaoka, Y. Takeda, O. Tamura, O. Muraoka, G. Tanabe, H. Ishibashi, Tetrahedron Lett., Tetrahedron Lett., 42(9), 1729 - 1732, Feb. 2001 , Refereed
  • Synthesis and reactivity of β-sulfonylvinylselenonium salts: a simple stereoselective synthesis of β-functionalized (Z)-vinyl sulfones, S. Watanabe, K. Yamamoto, Y. Itagali, T. Iwamura, T. Iwama, T. Kataoka, G. Tanabe, O. Muraoka, J. Chem. Soc., Perkin Trans. 1, J. Chem. Soc., Perkin Trans. 1, (3), 239 - 247, 2001 , Refereed
  • Percutaneous penetration of ozagrel and the enhancement produced by saturated fatty acids, T. Ogiso, K. Koike, M. Iwaki, T. Tanino, G. Tanabe, O. Muraoka, Biol. Pharm. Bull., Biol. Pharm. Bull., 23(7), 844 - 849, Jul. 2000 , Refereed
  • Reexamination of products and the reaction mechanism of the chalcogeno-Baylis-Hillman reaction: chalcogenide-TiCl4-mediated reactions of electron-deficient alkenes with aldehydes, T. Kataoka, H. Kinoshita, T. Iwama, S. Tsujiyama, T. Iwamura, O. Muraoka, G. Tanabe, Tetrahedron, Tetrahedron, 56(27), 4725 - 4731, Jul. 2000 , Refereed
  • Formation of 2-oxa or 2-azabicyclo[3.3.0]octa-3,7-diene by a novel tandem intramolecular photo-cyclization of 2,4,6-tris(phenylthio)hepta-2,4,6-trienal derivatives, M. Yoshimatsu, S. Gotoh, G. Tanabe, O. Muraoka, Chem. Commun., Chem. Commun., (10), 909 - 910, Jun. 1999 , Refereed
  • A new synthesis of α-amino acid thioesters by Pummerer reaction of 3-substituted-4-sulfinyl-β-sultams, T. Iwama, T. Kataoka, O. Muraoka, G. Tanabe, J. Org. Chem., J. Org. Chem., 63, 8355 - 8360, Nov. 1998 , Refereed
  • Enhancement of the Oral Bioavailability of Phenytoin by N-Aetylation and Absorptive Characteristics., T. Ogiso, T. Tanino, D. Kawaratani, M. Iwaki, G. Tanabe, O. Muraoka, Biol. Pharm. Bull., Biol. Pharm. Bull., 21(10), 1084 - 1089, Oct. 1998 , Refereed
  • Reactions of diphenyl(phenylethynyl)selenonium salts with active methylene compounds and amides: first isolation of oxyselenuranes [10-Se-4(C30)] as a reaction intermediate, T. Kataoka, S. Watanabe, K. Yamamoto, M. Yoshimatsu, G. Tanabe, O. Muraoka, J. Org. Chem., J. Org. Chem., 63, 6382 - 6386, Sep. 1998 , Refereed
  • Reactions of a β-sultam ring with lewis acids via the C-S bond cleavag, T. Iwama, M. Ogawa, T. Kataoka, O. Muraoka, G. Tanabe, Tetrahedron, Tetrahedron, 54(31), 8941 - 8974, Jul. 1998 , Refereed
  • Pummerer reaction of 2-vinylcyclopropyl sulfoxides: generation and reactions of butadienylthionium ion intermediates, T. Iwama, H. Matsumoto, H. Shimizu, T. Kataoka, O. Muraoka, G. Tanabe, J. Chem. Soc., Perkin Trans. 1, J. Chem. Soc., Perkin Trans. 1, 1569 - 1576, May 1998 , Refereed
  • Reactions of 1,2-thiazetidine 1,1-dioxides with organometallics: beta-elimination and N-S bond cleavage, T Iwama, T Kataoka, O Muraoka, G Tanabe, TETRAHEDRON, TETRAHEDRON, 54(21), 5507 - 5522, May 1998 , Refereed
    Summary:Reactions of 4-nonsubstituted beta-sultams 1 with methyllithium gave only (E)-vinylsulfonamides 2, whereas 2-aminoethyl sulfones 3 were obtained as minor products by use of methylmagnesium bromide. Reactions of 4-monosubstituted beta-sultams 6 with organolithiums gave (E)-vinylsulfonamides 7 stereoselectively regardless of the configuration of 3- and 4-substituents. Treatment of 4,4-dimethyl-beta-sultam 8a with methylmagnesium bromide and methyllithium provided 2-aminoethyl sulfone 9 and bis-sulfone 10, respectively, and isopropyl phenyl sulfone 11 was obtained by use of phenyllithium or phenylmagnesium bromide. (C) 1998 Elsevier Science Ltd. All rights reserved.
  • Stereoselective reduction of (±)-bicyclo[3.3.1]nonane-2,6-dione by microorganisms, M. Miyazawa, M. Nobata, S. Okamura, O. Muraoka, G. Tanabe, H. Kameoka, J. Chem. Technol., J. Chem. Technol., 71(4), 281 - 284, Apr. 1998 , Refereed
  • Enhancement of Oral Bioavailability of Phenytoin by Esterification, and in vitro Hydrolytic Characteristics of Products, T. Tanino, T. Ogiso, M. Iwaki, G. Tanabe, O. Muraoka, Int. J. Pharmaceut., Int. J. Pharmaceut., 163(1/2), 91 - 102, Mar. 1998 , Refereed
  • Furan-2(3H)- and -2(5H)-ones. Part 8. conformation and di-π-methane reactivity of the 4,7-disubstituted tetrahydroisobenzofuran-1-one system: a mechanistic and exploratory study, O. Muraoka, G. Tanabe, E. Yamamoto, M. Ono, T. Minematsu, T. Kimura, J. Chem. Soc, Perkin Trans. 1, J. Chem. Soc, Perkin Trans. 1, 2879 - 2890, Oct. 1997 , Refereed
  • Convenient synthesis of 2-alkynyl-cyclopropanes and –oxiranes, M. Yoshimatsu, S. Gotoh, E. Gotoh, G. Tanabe, O. Muraoka, J. Chem. Soc, Perkin Trans.1, J. Chem. Soc, Perkin Trans.1, 3035 - 3041, Oct. 1997 , Refereed
  • Furan-2(3H)- and -2(5H)-ones. Part 7. photochemical behaviour of tetrahydro- and hexahydro-isobenzofuran-1-one systems: a mechanistic and exploratory study, O. Muraoka, G. Tanabe, Y. Igaki, J. Chem. Soc, Perkin Trans. 1, J. Chem. Soc, Perkin Trans. 1, 1669 - 1679, Jun. 1997 , Refereed
  • Synthesis and reactions of lactam sulfonium salts with a sulfonio bridgehead. Part 1. 4,4a,5,6-tetrahydro-5-oxo-1H-thiopyrano[1,2-a]-1,4-benzothiazinium perchlorates, T. Kataoka, Y. Nakamura, H. Matsumoto, T. Iwama, H. Kondo, H. Shimizu, O. Muraoka, G. Tanabe, J. Chem. Soc, Parkin Trans. 1, J. Chem. Soc, Parkin Trans. 1, 309 - 316, Feb. 1997 , Refereed
  • Synthesis and reactions of lactam sulfonium salts with a sulfonio bridgehead. Part 2. 1,1a,4,5,6-pentahydro-6-oxo-2H-thiopyrano[1,6-d]-4,1-benzothiazepinium perchlorates, T. Kataoka, Y. Nakamura, H. Matsumoto, T. Iwama, H. Shimizu, O. Muraoka, G. Tanabe, Chem. Pharm. Bull., Chem. Pharm. Bull., 45(2), 265 - 271, Feb. 1997 , Refereed
  • Tandem Beckmann and Huisgen–White rearrangement of the 9-azabicyclo[3.3.1]nonan-3-one system. Part 2. The second mode of the rearrangement leading to 6-(prop-1-enyl)piperidin-2-ylacetic acid, a versatile intermediate for the syntheses of piperidine alkalo, O. Muraoka, B.-Z. Zheng, K. Okumura, E. Tabata, G. Tanabe, M. Kubo, J. Chem. Soc, Perkin Trans.1, J. Chem. Soc, Perkin Trans.1, 113 - 119, Jan. 1997 , Refereed
    Summary:Tandem Beckmann and Huisgen-White Rearrangement of the 9-Azabicyclo[3.3.1]nonan-3-one System. Part 2. The Second Mode of the Rearrangement Leading to [6-(Proden-1-yl)piperidin-2-yl]acetic Acid, a Versatile Intermediate for the Syntheses of Piperidine Alkaloids (+)-Pinidine and (+)-Monomorine I
  • Stereospecific syntheses of 5-alkyl-3-ethoxy-2-((phenylchalcogeno)- methylene)tetrahydrofurans, M. Yoshimatsu, M. Naito, H. Shimizu, O. Muraoka, G. Tanabe, T. Kataoka, J. Org. Chem., J. Org. Chem., 61(23), 8200 - 8206, Nov. 1996 , Refereed
  • Pharmacokinetics of indomethacin ester prodrugs: gastrointestinal and hepatic toxicity and the hydrolytic capacity of various tissues in rats, T. Ogiso, M. Iwaki, T. Tanino, T. Nagai, Y. Ueda, O. Muraoka, G. Tanabe, Biol. Pharm. Bull., Biol. Pharm. Bull., 19(9), 1178 - 1183, Sep. 1996 , Refereed
  • First successful [4++ 2]-type polar cycloadditions of 2-benzothiopyrylium salt with dienes, H. Shimizu, N. Araki, O. Muraoka, G. Tanabe, J. Chem. Soc., Chem. Commun., J. Chem. Soc., Chem. Commun., (18), 2185 - 2186, Sep. 1996 , Refereed
  • Photochemical behavior of ω-thiabicyclo[3.n.1]alkan-3-one: a mechanistic and exploratory study, O. Muraoka, B.-Z. Zheng, M. Nishimura, G. Tanabe, J. Chem. Soc. , Perkin Trans. 1, J. Chem. Soc. , Perkin Trans. 1, 1996, 2265 - 2270, Aug. 1996 , Refereed
  • Tandem Beckmann and Huisgen-White rearrangement as an alternative to the Baeyer-Villger oxidation of the 9-azabicyclo- [3.3.1]nonan-3-one system, first asymmetric synthesis of (-)-dihydropalustramic acid. X-ray molecular structure of 2β-ethyl-9-phenylsul, O. Muraoka, B.-Z. Zheng, K. Okumura, G. Tanabe, T. Momose, C. H. Eugster, J. Chem. Soc. , Perkin Trans. 1, J. Chem. Soc. , Perkin Trans. 1, 1567 - 1575, Jul. 1996 , Refereed
    Summary:Tandem Beckmann and Huisgen-White Rearrangement as an Alternative to the Baeyer-Villger Oxidation of the 9-Azabicyclo[3.3.1]nonan-3-one System, First Asymmetric Synthesis of(-)-Dihydtopalustramic Acid. X-Ray Molecular Structure of 2β-ethyl-9-phenylsulfonyl-9-azabicyclo-[3.3.1]nonan-3-one
  • A facile synthesis of 7-methylenebicyclo-[3.3.1]nonan-3-one and its transformation leading to the novel tricyclic system, protoadamantane, O. Muraoka, Yalou. Wang, M. Okumura, S. Nishiura, G. Tanabe, T. Momose, Synth. Commun., Synth. Commun., 26(8), 1555 - 1562, Apr. 1996 , Refereed
  • Enantioselective total synthesis of the di-O-methyl ethers of (–)-agatharesinol, (+)-hinokiresinol and (–)-sugiresinol, characteristic norlignans of Coniferae, O. Muraoka, B.-Z. Zheng, N. Fujiwara, G. Tanabe, J. Chem. Soc. , Rerkin Trans. 1, J. Chem. Soc. , Rerkin Trans. 1, 1996, 405 - 411, Mar. 1996 , Refereed
  • Furan-2(3H)- and -2(5H)-ones. Part 6. di-π-methane rearrangement of the α-substituted 4-benzylfuran-2(5H)-one system, O. Muraoka, G. Tanabe, M. Higashiura, T. Minematsu, T. Momose, J. Chem. Soc., Perkin Trans. 1, J. Chem. Soc., Perkin Trans. 1, 1437 - 1443, Jun. 1995 , Refereed
  • Norrish type I photo-cleavage of 9-oxabicyclo[3.3.1]nonan-3-one: a straightforward synthesis of (±)-(cis-6-methyltetrahydropyran-2-yl)acetic acid, a constituent of civet, O. Muraoka, M. Okumura, T. Maeda, L. Wang, G. Tanabe, Chem. Pharm. Bull., Chem. Pharm. Bull., 43(3), 517 - 519, Mar. 1995 , Refereed
  • Physicochemical and hydrolytic characteristics of phenytoin derivatives, T. Ogiso, T. Tanino, M. Iwaki, O. Muraoka, G. Tanabe, Biol. Pharm. Bull., Biol. Pharm. Bull., 17(10), 1425 - 1429, Oct. 1994 , Refereed
  • Furan-2(3H)- and 2(5H)-ones. Part 5. Photoreactions of 3-benzylfuran-2(5H)-ones; cyclisation to indenofuranones, O. Muraoka, G. Tanabe, K. Sano, T. Minematsu, T. Momose, J. Chem. Soc., Perkin Trans. 1, J. Chem. Soc., Perkin Trans. 1, 1833 - 1845, Jul. 1994 , Refereed
  • THE NORRISH TYPE-I PHOTO-CLEAVAGE OF (+)-2-BETA-ETHYL-9-AZABICYCLO[3.3.1]NONAN-3-ONE - A SHORT, ENANTIOSELECTIVE FORMAL SYNTHESIS OF (-)-INDOLIZIDINE-223AB, O MURAOKA, K OKUMURA, T MAEDA, G TANABE, T MOMOSE, TETRAHEDRON-ASYMMETRY, TETRAHEDRON-ASYMMETRY, 5(3), 317 - 320, Mar. 1994 , Refereed
    Summary:The enantioselective alkylation of the ''fork head ketone'' (1) followed by the Norrish Type I photo-cleavage provided the short enantioselective synthesis of (-)-indolizidine 223AB (4).
  • Pharmacokinetic analysis of phenytoin and its derivatives in plasma and brain in rats, T. Ogiso, M. Iwaki, T. Tanino, O. Muraoka, G. Tanabe, Biol. Pharm. Bull., Biol. Pharm. Bull., 16(10), 1025 - 1030, Oct. 1993 , Refereed
  • Tandem Beckmann and Huisgen-White rearrangement of the 9-azabicyclo[3.3.1]nonan-3-one System: a facile route to (±)-dihydropalustramic acid, T. Momose, K. Okumura, H. Tsujimori, K. Inokawa, G. Tanabe, Osamu Muraoka, Y. Sasaki, C. H. Eugster, Heterocycles, Heterocycles, 36, 7 - 11, Jan. 1993 , Refereed
  • Chalcones as synthetic intermediates. A facile synthesis of (±)-magnosalicin, an antiallergy neolignan, O. Muraoka, T. Sawada, E. Morimoto, G. Tanabe, Chem. Pharm. Bull., Chem. Pharm. Bull., 41(4), 772 - 774, Jan. 1993 , Refereed
  • 2(3H)- and 2(5H)-Furanones. IV. The di-p-methane rearrangement of 3,4-bis(phenylmethyl)-2(5H)-furanone, T. Momose, G. Tanabe, H. Tujimori, O. Muraoka, Chem. Pharm. Bull., Chem. Pharm. Bull., 40(9), 2525 - 2530, Sep. 1992 , Refereed
  • A breakthrough for the photochemical arylation in the 3-(phenylmethyl)-2(5H)-furanone system leading to the tetrahydroindenofuranone system, O. Muraoka, G. Tanabe, K. Sano, T. Momose, Heterocycles, Heterocycles, 34, 1093 - 1096, May 1992 , Refereed
  • First asymetric synthesis of (-)-sugiresinol dimethyl ether, O. Muraoka, B.-Z. Zheng, N. Fujiwara, G. Tanabe, Tetrahedron : Asymmetry, Tetrahedron : Asymmetry, 2(5), 357 - 358, May 1991 , Refereed
  • ACCENTUATION OF THE DI-PI-METHANE REACTIVITY BY CENTRAL CARBON SUBSTITUTION IN THE 4-(PHENYLMETHYL)-2(5H)-FURANONE SYSTEM, O MURAOKA, G TANABE, T MOMOSE, HETEROCYCLES, HETEROCYCLES, 31(9), 1589 - 1592, Sep. 1990 , Refereed
  • THE DI-PI-METHANE REARRANGEMENT IN 3,4-DIBENZYL-2(5H)-FURANONE, T MOMOSE, G TANABE, H TSUJIMORI, M HIGASHIURA, IMANISHI, I, K KANAI, HETEROCYCLES, HETEROCYCLES, 29(2), 257 - 262, Feb. 1989 , Refereed
  • Visualizing the Adenylation Activities and Protein-Protein Interactions of Aryl Acid Adenylating Enzymes, Fumihiro Ishikawa, Shota Kasai, Hideaki Kakeya, Genzoh Tanabe, CHEMBIOCHEM, CHEMBIOCHEM, 18(22), 2199 - 2204, Nov. 2017 , Refereed
    Summary:Structural and activity studies have revealed the dynamic and transient actions of carrier protein (CP) activity in primary and secondary metabolic pathways. CP-mediated interactions play a central role in nonribosomal peptide biosynthesis, as they serve as covalent tethers for amino acid and aryl acid substrates and enable the growth of peptide intermediates. Strategies are therefore required to study protein-protein interactions efficiently. Herein, we describe activity-based probes used to demonstrate the protein-protein interactions between aryl CP (ArCP) and aryl acid adenylation (A) domains as well as the substrate specificities of the aryl acid Adomains. If coupled with in-gel fluorescence imaging, this strategy allows visualization of the protein-protein interactions required to recognize and transfer the substrate to the partner ArCP. This technique has potential for the analysis of protein-protein interactions within these biosynthetic enzymes at the molecular level and for use in the combinatorial biosynthesis of new nonribosomal peptides.
  • Total syntheses of the aromatase inhibitors, mammeasins C and D, from Thai medicinal plant Mammea siamensis, Genzoh Tanabe, Nozomi Tsutsui, Kanae Shibatani, Shinsuke Marumoto, Fumihiro Ishikawa, Kiyofumi Ninomiya, Osamu Muraoka, Toshio Morikawa, TETRAHEDRON, TETRAHEDRON, 73(30), 4481 - 4486, Jul. 2017 , Refereed
    Summary:The first total syntheses of the geranylated pyranocoumarins, mameasins C (1) and D (2), aromatase inhibitors isolated from the flowers of Mammea siamensis, were accomplished in five steps, starting from phloroglucinol 3. In this strategy, the characteristic pyran ring-fused coumarin core of 1 and 2 was effectively constructed by Friedel-Crafts acylation of 3, followed by Reformatsky reaction of the resultant ketone to give a key coumarin intermediate 9. Compound 9 was converted to targets 1 and 2 in a stepwise manner by successive C-acylation and O-geranylation, followed by a [1,3]-sigmatropic geranyl shift. Furthermore, screening of intermediates obtained in the synthetic pathway to 1 and 2 revealed that de-geranylated pyranocoumarins (10 and 11) show superior aromatase inhibitory activity as compared to the natural products 1 and 2. (C) 2017 Elsevier Ltd. All rights reserved.
  • Identification of ACA-28, a 1 '-acetoxychavicol acetate analogue compound, as a novel modulator of ERK MAPK signaling, which preferentially kills human melanoma cells, Ryosuke Satoh, Kanako Hagihara, Kazuki Matsuura, Yoshiaki Manse, Ayako Kita, Tatsuki Kunoh, Takashi Masuko, Mariko Moriyama, Hiroyuki Moriyama, Genzoh Tanabe, Osamu Muraoka, Reiko Sugiura, GENES TO CELLS, GENES TO CELLS, 22(7), 608 - 618, Jul. 2017 , Refereed
    Summary:The extracellular signal-regulated kinase (ERK) signaling pathway is essential for cell proliferation and is frequently deregulated in human tumors such as melanoma. Melanoma remains incurable despite the use of conventional chemotherapy; consequently, development of new therapeutic agents for melanoma is highly desirable. Here, we carried out a chemical genetic screen using a fission yeast phenotypic assay and showed that ACA-28, a synthetic derivative of 10-acetoxychavicol acetate (ACA), which is a natural ginger compound, effectively inhibited the growth of melanoma cancer cells wherein ERK MAPK signaling is hyperactivated due to mutations in the upstream activating regulators. ACA-28 more potently inhibited the growth of melanoma cells than did the parental compound ACA. Importantly, the growth of normal human epidermal melanocytes (NHEM) was less affected by ACA-28 at the same 50% inhibitory concentration. In addition, ACA-28 specifically induced apoptosis in NIH/3T3 cells which were oncogenically transformed with human epidermal growth factor receptor-2 (HER2/ErbB2), but not in the parental cells. Notably, the ACA-28-induced apoptosis in melanoma and HER2-transformed cells was abrogated when ERK activation was blocked with a specific MEK inhibitor U0126. Consistently, ACA-28 more strongly stimulated ERK phosphorylation in melanoma cells, as compared in NHEM. ACA-28 might serve as a promising seed compound for melanoma treatment.
  • Mangiferin, a novel nuclear factor kappa B-inducing kinase inhibitor, suppresses metastasis and tumor growth in a mouse metastatic melanoma model., Tomoya Takeda, Masanobu Tsubaki, Kotaro Sakamoto, Eri Ichimura, Aya Enomoto, Yuri Suzuki, Tatsuki Itoh, Motohiro Imano, Genzoh Tanabe, Osamu Muraoka, Hideaki Matsuda, Takao Satou, Shozo Nishida, Toxicology and applied pharmacology, Toxicology and applied pharmacology, 306, 105 - 12, Sep. 01 2016 , Refereed
    Summary:Advanced metastatic melanoma, one of the most aggressive malignancies, is currently without reliable therapy. Therefore, new therapies are urgently needed. Mangiferin is a naturally occurring glucosylxanthone and exerts many beneficial biological activities. However, the effect of mangiferin on metastasis and tumor growth of metastatic melanoma remains unclear. In this study, we evaluated the effect of mangiferin on metastasis and tumor growth in a mouse metastatic melanoma model. We found that mangiferin inhibited spontaneous metastasis and tumor growth. Furthermore, mangiferin suppressed the nuclear translocation of nuclear factor kappa B (NF-κB) and expression of phosphorylated NF-κB-inducing kinase (NIK), inhibitor of kappa B kinase (IKK), and inhibitor of kappa B (IκB) and increases the expression of IκB protein in vivo. In addition, we found that mangiferin inhibited the expression of matrix metalloproteinases (MMPs) and very late antigens (VLAs) in vivo. Mangiferin treatment also increased the expression of cleaved caspase-3, cleaved Poly ADP ribose polymerase-1 (PARP-1), p53 upregulated modulator of apoptosis (PUMA), p53, and phosphorylated p53 proteins, and decreased the expression of Survivin and Bcl-associated X (Bcl-xL) proteins in vivo. These results indicate that mangiferin selectivity suppresses the NF-κB pathway via inhibition of NIK activation, thereby inhibiting metastasis and tumor growth. Importantly, the number of reported NIK selective inhibitors is limited. Taken together, our data suggest that mangiferin may be a potential therapeutic agent with a new mechanism of targeting NIK for the treatment of metastatic melanoma.
  • Quantitative Determination of Alkaloids in Lotus Flower (Flower Buds of Nelumbo nucifera) and Their Melanogenesis Inhibitory Activity, Toshio Morikawa, Niichiro Kitagawa, Genzoh Tanabe, Kiyofumi Ninomiya, Shuhei Okugawa, Chiaki Motai, Iyori Kamei, Masayuki Yoshikawa, I-Jung Lee, Osamu Muraoka, MOLECULES, MOLECULES, 21(7), 931, Jul. 2016 , Refereed
    Summary:A quantitative analytical method for five aporphine alkaloids, nuciferine (1), nornuciferine (2), N-methylasimilobine (3), asimilobine (4), and pronuciferine (5), and five benzylisoquinoline alkaloids, armepavine (6), norarmepavine (7), N-methylcoclaurine (8), coclaurine (9), and norjuziphine (10), identified as the constituents responsible for the melanogenesis inhibitory activity of the extracts of lotus flowers (the flower buds of Nelumbo nucifera), has been developed using liquid chromatography-mass spectrometry. The optimum conditions for separation and detection of these 10 alkaloids were achieved on a NAP column, a reversed-phase column with naphthylethyl group-bonded silica packing material, with CH3CN-0.2% aqueous acetic acid as the mobile phase and using mass spectrometry equipped with a positive-mode electrospray ionization source. According to the protocol established, distributions of these 10 alkaloids in the petal, receptacle, and stamen parts, which were separated from the whole flower, were examined. As expected, excellent correlations were observed between the total alkaloid content and melanogenesis inhibitory activity. Among the active alkaloids, nornuciferine (2) was found to give a carbamate salt (2) via formation of an unstable carbamic acid (2) by absorption of carbon dioxide from the air.
  • Mangiferin induces apoptosis in multiple myeloma cell lines by suppressing the activation of nuclear factor kappa B-inducing kinase., Tomoya Takeda, Masanobu Tsubaki, Toshiki Kino, Misa Yamagishi, Megumi Iida, Tatsuki Itoh, Motohiro Imano, Genzoh Tanabe, Osamu Muraoka, Takao Satou, Shozo Nishida, Chemico-biological interactions, Chemico-biological interactions, 251, 26 - 33, May 05 2016 , Refereed
    Summary:Mangiferin is a naturally occurring glucosyl xanthone, which induces apoptosis in various cancer cells. However, the molecular mechanism underlying mangiferin-induced apoptosis has not been clarified thus far. Therefore, we examined the molecular mechanism underlying mangiferin-induced apoptosis in multiple myeloma (MM) cell lines. We found that mangiferin decreased the viability of MM cell lines in a concentration-dependent manner. We also observed an increased number of apoptotic cells, caspase-3 activation, and a decrease in the mitochondrial membrane potential. In addition, mangiferin inhibited the nuclear translocation of nuclear factor kappa B (NF-κB) and expression of phosphorylated inhibitor kappa B (IκB) and increased the expression of IκB protein, whereas no changes were observed in the phosphorylation levels of extracellular signal-regulated kinase 1/2 (ERK1/2), c-Jun N-terminal protein kinase 1/2 (JNK1/2), and mammalian target of rapamycin (mTOR). The molecular mechanism responsible for mangiferin-induced inhibition of nuclear translocation of NF-κB was a decrease in the expression of phosphorylated NF-κB-inducing kinase (NIK). Moreover, mangiferin decreased the expression of X-linked inhibitor of apoptosis protein (XIAP), survivin, and Bcl-xL proteins. Knockdown of NIK expression showed results similar to those observed with mangiferin treatment. Our results suggest that mangiferin induces apoptosis through the inhibition of nuclear translocation of NF-κB by suppressing NIK activation in MM cell lines. Our results provide a new insight into the molecular mechanism of mangiferin-induced apoptosis. Importantly, since the number of reported NIK inhibitors is limited, mangiferin, which targets NIK, may be a potential anticancer agent for the treatment of MM.
  • Synthesis of Azepines via a [6+1] Annulation of Ynenitriles with Refornnatsky Reagents, Mitsuhiro Yoshimatsu, Miki Tanaka, Yu Fujimura, Yukiteru Ito, Yusuke Goto, Yuka Kobayashi, Hiroaki Wasada, Noriyuki Hatae, Genzoh Tanabe, Osamu Muraoka, JOURNAL OF ORGANIC CHEMISTRY, JOURNAL OF ORGANIC CHEMISTRY, 80(19), 9480 - 9494, Oct. 2015 , Refereed
    Summary:A protocol for the direct synthesis of azepines using a hafnium(III)-catalyzed [6 + 1] annulation of N-tethered ynenitriles with Reformatsky reagents is reported. A broad range of 3-amino-2,7-dihydro-1H-azepine-4-carboxylates 4aa-4he were obtained in high yields and with excellent functional group tolerance. The copper-mediated reactions of isolable Blaise intermediates (enamino esters 3), uniquely underwent beta-endo cydization to afford the beta-2,5-dihydropyrrolyl alpha,beta-unsaturated esters 5aa-5fc, which exhibit anticancer activity.
  • Structure-activity relationship studies on acremomannolipin A, the potent calcium signal modulator with a novel glycolipid structure 3: Role of the length of alditol side chain, Nozomi Tsutsui, Genzoh Tanabe, Nao Morita, Yoshitomo Okayama, Ayako Kita, Reiko Sugiura, Osamu Muraoka, BIOORGANIC & MEDICINAL CHEMISTRY, BIOORGANIC & MEDICINAL CHEMISTRY, 23(13), 3761 - 3773, Jul. 2015 , Refereed
    Summary:Five homologs of a novel glycolipid acremomannolipin A (1a), the potential Ca2+ signal modulator isolated from Acremonium strictum, bearing alditols of different length (1g-1k) were synthesized by a stereoselective beta-mannosylation of appropriately protected mannosyl sulfoxide (2) with five alditols (1g: C2, 1h: C3, 1i: C4, 1j: C5 and 1k: C7 units), and their potential in modulating Ca2+ signaling were evaluated. Homologs with alditols of more than 4 carbons (1i, 1j and 1k) were equally or more potent than the parent compound (1a) regardless of the length of the alditol chain. Whereas activities of two homologs with shorter chains (1g and 1h) decreased to a considerable extent. The results indicated that the length of the alditol side chain was a crucial determinant for the potent calcium signal modulating activity. (C) 2015 Elsevier Ltd. All rights reserved.
  • Salacinol and Related Analogs: New Leads for Type 2 Diabetes Therapeutic Candidates from the Thai Traditional Natural Medicine Salacia chinensis, Toshio Morikawa, Junji Akaki, Kiyofumi Ninomiya, Eri Kinouchi, Genzoh Tanabe, Yutana Pongpiriyadacha, Masayuki Yoshikawa, Osamu Muraoka, NUTRIENTS, NUTRIENTS, 7(3), 1480 - 1493, Mar. 2015 , Refereed
    Summary:The antidiabetic effect of a hot water extract of stems of Salacia chinensis (SCE) was evaluated in vivo in KK-A(y) mice, a typical type 2 diabetes mellitus mice model. Administration of CE-2 dietary feed containing 0.25 and/or 0.50% of SCE for three weeks to KK-A(y) mice significantly suppressed the elevation of both blood glucose and HbA1c levels without significant changes in body weight or food intake. Glucose tolerance was improved by administration to KK-A(y) mice for 27 days of AIN93M purified dietary feed containing 0.12% of SCE. No suppressive effect with respect to HbA1c level was observed when AIN93M/Glc dietary feed in which all digestible glucides were replaced with glucose was administered with SCE. Thus, alpha-glucosidase inhibitory activity approved as the mechanism of action of the antidiabetic effect of SCE by in vitro investigation was reconfirmed also in in vivo studies. Evaluation of the alpha-glucosidase inhibitory activity of the active constituents, salacinol (1), kotalanol (3), and neokotalanol (4), by employing human alpha-glucosidases revealed that these compounds inhibited them as potently (IC50 = 3.9-4.9 mu M for maltase) as they inhibited rat small intestinal alpha-glucosidase. The principal sulfonium constituents (1-4) were highly stable in an artificial gastric juice. In addition, 1-4 were hardly absorbed from the intestine in an experiment using the in situ rat ligated intestinal loop model. The results indicate that these sulfoniums are promising leads for a new type of anti-diabetic agents.
  • Construction of 3,6-Anhydrohexosides via Intramolecular Cyclization of Triflates and Its Application to the Synthesis of Natural Product Isolated from Leaves of Sauropus rostratus, Long Liu, Cheng-Qian Wang, Dan Liu, Wei-Gang He, Jin-Yi Xu, Ai-Jun Lin, He-Quan Yao, Genzoh Tanabe, Osamu Muraoka, Wei-Jia Xie, Xiao-Ming Wu, ORGANIC LETTERS, ORGANIC LETTERS, 16(19), 5004 - 5007, Oct. 2014 , Refereed
    Summary:A novel synthetic approach to construct various 3,6-anhydrohexosides via an intramolecular cyclization of corresponding triflates is described. The nucleophilic attack from C3 p-methoxybenzylated hydroxyl to C6 trifluoromethanesulfonate on triflate structures triggered the cyclization reaction to provide 3,6-anhydrohexosides in excellent yields, making the strategy more efficient with respect to the reported protocols. By applying this methodology, a concise first total synthesis of natural product isolated from leaves of Sauropus rostratus was accomplished.
  • Structure-activity relationship studies on acremomannolipin A, the potent calcium signal modulator with a novel glycolipid structure 2: Role of the alditol side chain stereochemistry, Nozomi Tsutsui, Genzoh Tanabe, Genki Gotoh, Nao Morita, Naohisa Nomura, Ayako Kita, Reiko Sugiura, Osamu Muraoka, BIOORGANIC & MEDICINAL CHEMISTRY, BIOORGANIC & MEDICINAL CHEMISTRY, 22(3), 945 - 959, Feb. 2014 , Refereed
    Summary:Five alditol analogs 1b-1f of a novel glycolipid acremomannolipin A (1a), the potential Ca2+ signal modulator isolated from Acremonium strictum, were synthesized by employing a stereoselective beta-mannosylation of appropriately protected mannose with five hexitols with different stereochemistry, and their potential on modulating Ca2+ signaling were evaluated. All these analogs were more potent compared to the original compound 1a, and proved that mannitol stereochemistry of 1a was not critical for the potent calcium signal modulating. (C) 2014 Elsevier Ltd. All rights reserved.
  • Practical synthesis of neoponkoranol and its related sulfonium salt, an optimised protocol using isopropylidene as an effective protecting group, Dan Liu, Weijia Xie, Long Liu, Jinyi Xu, Hequan Yao, Genzoh Tanabe, Osamu Muraoka, Xiaoming Wu, JOURNAL OF CHEMICAL RESEARCH, JOURNAL OF CHEMICAL RESEARCH, (12), 715 - 719, Dec. 2013 , Refereed
    Summary:A practical synthesis of neoponkoranol and its related sulfonium salt as potent a-glucosidase inhibitors has been developed in which the key step of coupling reaction was optimised by using isopropylidene as an effective protecting group. The characteristic intramolecular cyclisation of the coupling precursor previously encountered as a side reaction has not been detected and coupling yields were dramatically improved in the present study.
  • Stereoselective total synthesis of acremomannolipin A and its anomer, the potent calcium signal modulators with a novel glycolipid structure: role of the stereochemistry at the anomeric center on the activity, Nozomi Tsutsui, Genzoh Tanabe, Genki Gotoh, Ayako Kita, Reiko Sugiura, Osamu Muraoka, TETRAHEDRON, TETRAHEDRON, 69(47), 9917 - 9930, Nov. 2013
    Summary:A full account of stereoselective total synthesis of a novel glycolipid, acremomannolipin A (1), the potent calcium signal modulator isolated from Acremonium strictum, by employing the stereoselective beta-mannosylation of 4,6-O-benzylidene-protected mannosyl sulfoxide with D-mannitol as the key reaction is described. The alpha-anomer (epi-1) of 1 was also synthesized selectively. The calcium modulating activity was reduced upon inversion of the configuration at the anomeric center, indicating that the beta-configuration of the mannose moiety is preferable for the activity. (C) 2013 Elsevier Ltd. All rights reserved.
  • Clostridium scindens: a human gut microbe with a high potential to convert glucocorticoids into androgens, Jason M. Ridlon, Shigeo Ikegawa, Joao M. P. Alves, Biao Zhou, Akiko Kobayashi, Takashi Iida, Kuniko Mitamura, Genzoh Tanabe, Myrna Serrano, Ainee De Guzman, Patsy Cooper, Gregory A. Buck, Phillip B. Hylemon, JOURNAL OF LIPID RESEARCH, JOURNAL OF LIPID RESEARCH, 54(9), 2437 - 2449, Sep. 2013 , Refereed
    Summary:Clostridium scindens American Type Culture Collection 35704 is capable of converting primary bile acids to toxic secondary bile acids, as well as converting glucocorticoids to androgens by side-chain cleavage. The molecular structure of the side-chain cleavage product of cortisol produced by C. scindens was determined to be 11 beta-hydroxyandrost-4-ene-3,17-dione (11 beta-OHA) by high-resolution mass spectrometry, H-1 and C-13 NMR spectroscopy, and X-ray crystallography. Using RNA-Seq technology, we identified a cortisol-inducible (similar to 1,000-fold) operon (des ABCD) encoding at least one enzyme involved in anaerobic side-chain cleavage. The des C gene was cloned, overexpressed, purified, and found to encode a 20 alpha-hydroxysteroid dehydrogenase (HSDH). This operon also encodes a putative "transketolase" (des AB) hypothesized to have steroid-17,20-desmolase/oxidase activity, and a possible corticosteroid transporter (des D). RNA-Seq data suggests that the two-carbon side chain of glucocorticords may feed into the pentose-phosphate pathway and are used as a carbon source. The 20 alpha-HSDH is hypothesized to function as a metabolic "rheostat" controlling rates of side-chain cleavage. Phylogenetic analysis suggests this operon is rare in nature and the des C gene evolved from a gene encoding threonine dehydrogenase.jlr The physiological effect of 11 beta-OHAD on the host or other gut microbes is currently unknown.
  • Alkaloid constituents from flower buds and leaves of sacred lotus (Nelumbo nucifera, Nymphaeaceae) with melanogenesis inhibitory activity in B16 melanoma cells, Seikou Nakamura, Souichi Nakashima, Genzo Tanabe, Yoshimi Oda, Nami Yokota, Katsuyoshi Fujimoto, Takahiro Matsumoto, Rika Sakuma, Tomoe Ohta, Keiko Ogawa, Shino Nishida, Hisako Miki, Hisashi Matsuda, Osamu Muraoka, Masayuki Yoshikawa, BIOORGANIC & MEDICINAL CHEMISTRY, BIOORGANIC & MEDICINAL CHEMISTRY, 21(3), 779 - 787, Feb. 2013 , Refereed
    Summary:Methanolic extracts from the flower buds and leaves of sacred lotus (Nelumbo nucifera, Nymphaeaceae) were found to show inhibitory effects on melanogenesis in theophylline-stimulated murine B16 melanoma 4A5 cells. From the methanolic extracts, a new alkaloid, N-methylasimilobine N-oxide, was isolated together with eleven benzylisoquinoline alkaloids. The absolute stereostructure of the new alkaloid was determined from chemical and physicochemical evidence. Among the constituents isolated, nuciferine, N-methylasimilobine, (-)-lirinidine, and 2-hydroxy-1-methoxy-6a, 7-dehydroaporphine showed potent inhibition of melanogenesis. Comparison of the inhibitory activities of synthetic related alkaloids facilitated characterization of the structure-activity relationships of aporphine-and benzylisoquinoline-type alkaloids. In addition, 3-30 mu M nuciferine and N-methylasimilobine inhibited the expression of tyrosinase mRNA, 3-30 mu M N-methylasimilobine inhibited the expression of TRP-1 mRNA, and 10-30 mu M nuciferine inhibited the expression of TRP-2 mRNA. (C) 2012 Elsevier Ltd. All rights reserved.
  • The first total synthesis of acremomannolipin A, the potential Ca2+ signal modulator with a characteristic glycolipid structure, isolated from the filamentous fungus Acremonium strictum, Nozomi Tsutsui, Genzoh Tanabe, Ayako Kita, Reiko Sugiura, Osamu Muraoka, TETRAHEDRON LETTERS, TETRAHEDRON LETTERS, 54(6), 451 - 453, Feb. 2013
    Summary:The first total synthesis of acremomannolipin A, the potential Ca2+ signal modulator isolated from Acremonium strictum, was achieved by employing the characteristic stereoselective beta-mannosylation of 4,6-O-benzylidene-protected mannosyl sulfoxide with a D-mannitol derivative in the presence of trifluoromethanesulfonic anhydride as the key reaction. (C) 2012 Elsevier Ltd. All rights reserved.
  • Copper-Catalyzed Complete Regio- and Stereoselective Cyclization of 1-Aryl-3-sulfanyl-4-oxahepta-1,6-diynes Triggered by Alkynylation, Mitsuhiro Yoshimatsu, Hitomi Sasaki, Yuko Sugimoto, Yuya Nagase, Genzoh Tanabe, Osamu Muraoka, ORGANIC LETTERS, ORGANIC LETTERS, 14(12), 3190 - 3193, Jun. 2012 , Refereed
    Summary:Copper(I)-catalyzed alkynylation-cyclization of 4-oxahepta-1,6-diynes 1 with a wide variety of terminal alkynes proceeded to give (3E,4Z)-3-(phenylsulfanylmethylene)-4-(2-propynylidene)tetrahydrofuran-2-yl]benzenes 2aa-he in high yields with complete regio- and stereoselectivity.
  • Synthesis of 3-methyl- and 3,4-dimethylfurans using alkoxide, thiolate, and phenoxide-mediated cyclization of 4-oxahepta-1,6-diynes bearing sulfur and selenium functional groups, Nami Takahashi, Yuya Nagase, Genzoh Tanabe, Osamu Muraoka, Mitsuhiro Yoshimatsu, TETRAHEDRON, TETRAHEDRON, 68(5), 1566 - 1580, Feb. 2012 , Refereed
    Summary:We have reported sodium alkoxide- or aryloxide-mediated cyclization of 4-oxahepta-1,6-diynes bearing the phenylsulfanyl group 1a-d. The reactions with diverse sodium alkoxides and aryloxide produced 4-alkoxymethyl- and 4-aryloxymethylfurans 2aa-2db in good to high yields. Although reactions with sodium benzenethiolate yielded 3,4-bis(phenylsulfanylmethyl)furans 5a-g, they readily desulfanylated in the presence of tributyltin hydride/AIBN to give the 3-methyl- and 3,4-dimethylfuran derivatives 6a-g. This method's utility was demonstrated by the synthesis of tetrahydronaphthalenyl furan derivatives bearing alkoxy- and aryloxymethyl substituents. (C) 2011 Elsevier Ltd. All rights reserved.
  • Another mode of heterocyclization of an enantiopure C-2-symmetric bis-epoxide leading to the symmetric dialkyl sulfide, Weijia Xie, Genzoh Tanabe, Hiroyuki Morimoto, Takanori Hatanaka, Toshie Minematsu, Xiaoming Wu, Osamu Muraoka, TETRAHEDRON, TETRAHEDRON, 66(38), 7487 - 7491, Sep. 2010 , Refereed
    Summary:Reexamination of heterocyclization of an enantiopure C-2-symmetric bis-epoxide (7) with sodium sulfide is described. In addition to the reported processes leading to thiane (4a) and thiepane (6), another mode of cyclization was found to occur to a considerable extent, affording a symmetric dialkyl sulfide (5), and the structure of the main product reported (4a) has been revised. Conditions for the chemoselective formation of 6 were established, and effective transformation of 6 into 4 was accomplished by the modification of the processes. (C) 2010 Elsevier Ltd. All rights reserved.
  • Scandium-Catalyzed Propargylation of 1,3-Diketones with Propargyl Alcohols Bearing Sulfur or Selenium Functional Groups: Useful Transformation to Furans and Pyrans, Katsuki Ohta, Taira Kobayashi, Genzoh Tanabe, Osamu Muraoka, Mitsuhiro Yoshimatsu, CHEMICAL & PHARMACEUTICAL BULLETIN, CHEMICAL & PHARMACEUTICAL BULLETIN, 58(9), 1180 - 1186, Sep. 2010 , Refereed
    Summary:Propargylations of 1,3-diketones using 3-sulfanyl and 3-selanylpropargyl alcohols 1 in MeNO2-H2O gave alkynyl ketones 2a-m, 2o-v and 6,7-dihydro-5H-cyclohexa[b]pyran-5-ones 3k-n. With some bases, the useful propargylated 1,3-diketones underwent intramolecular cyclization to give 6,7-dihydro-5H-benzofuran-4-ones 4a-i or 4,5,6,7-tetrahydrobenzofurans 5p, 6p-v.
  • Characteristic alkaline catalyzed degradation of kotalanol, a potent alpha-glucosidase inhibitor isolated from Ayurvedic traditional medicine Salacia reticulata, leading to anhydroheptitols: another structural proof, Osamu Muraoka, Weijia Xie, Satomi Osaki, Ayumi Kagawa, Genzoh Tanabe, Mumen F. A. Amer, Toshie Minematsu, Toshio Morikawa, Masayuki Yoshikawa, TETRAHEDRON, TETRAHEDRON, 66(21), 3717 - 3722, May 2010 , Refereed
    Summary:Stereochemical structure of kotalanol (2), a highly potent a-glucosidase inhibitor isolated from an Ayurvedic traditional medicine Salacia reticulata, was proved by alkaline catalyzed degradation of natural kotalanol (2), in which characteristic stereospecific cyclization of the degradative side chain leading to anhydroheptitols (10 and 11) was involved. (C) 2010 Elsevier Ltd. All rights reserved.
  • On the structure of the bioactive constituent from ayurvedic medicine Salacia reticulata: revision of the literature, Osamu Muraoka, Weijia Xie, Genzoh Tanabe, Mumen F. A. Amer, Toshie Minematsu, Masayuki Yoshikawa, TETRAHEDRON LETTERS, TETRAHEDRON LETTERS, 49(51), 7315 - 7317, Dec. 2008 , Refereed
    Summary:The reported structure of a potent a-glucosidase inhibitor 7 isolated recently from ayurvedic medicine Salacia reticulata was found incorrect, and the compound was proved to be de-O-sulfated kotalanol 4. Discussion and detailed analysis of the spectral data leading to the revised structure are presented. (C) 2008 Elsevier Ltd. All rights reserved.
  • Synthesis and elucidation of absolute stereochemistry of salaprinol, another thiosugar sulfonium sulfate from the ayurvedic traditional medicine Salacia prinoides, Genzoh Tanabe, Mika Sakano, Toshie Minematsu, Hisashi Matusda, Masayuki Yoshikawa, Osamu Muraoka, TETRAHEDRON, TETRAHEDRON, 64(43), 10080 - 10086, Oct. 2008 , Refereed
    Summary:Synthesis and elucidation of absolute stereochemistry of salaprinol (3) isolated from the root and sterns of Salacia prinoides, which has been used for the treatment of diabetes in India, Sri Lanka, and Southeast Asia countries, is described. Compound 3 and its 2'-epimer, epi-salaprinol (epi-3) were synthesized via the coupling reaction of a cyclic sulfate, 2-O-benzylglycerol 1,3-cyclic sulfate (S), with a thiosugar, 1,4-dideoxy-1,4-epithio-D-arabinitol (6), as the key reaction, and S configuration of the asymmetric center in the side chain of 3 was elucidated by the X-ray crystallographic analysis. (C) 2008 Published by Elsevier Ltd.
  • A new method of constructing dearomatized compounds using triazene, Keiji Nishiwaki, Takashi Ogawa, Ken-ichi Tagami, Genzoh Tanabe, Osamu Muraoka, Keizo Matsuo, TETRAHEDRON, TETRAHEDRON, 62(47), 10854 - 10858, Nov. 2006 , Refereed
    Summary:We are reporting on a new method of constructing dearomatized compounds from alpha-substituted aryltriazenes. Deprotonation occurs at C atom alpha to N3. Nucleophilic attack of generated anion at the ortho-position of aryl group forms a new carbon-carbon bond. A stereoselective reaction was observed when the substituents on the C alpha to N3 are tied together in either a pyrrolidine or a piperidine. The product of this reaction possessed an interesting dearomatized tetrahydrobenzotriazine framework. (c) 2006 Elsevier Ltd. All rights reserved.
  • Asymmetric tandem Michael-aldol reactions between 3-cinnamoyloxazolidine-2-thiones and aldehydes, Hironori Kinoshita, Takashi Osamura, Kazumi Mizuno, Sayaka Kinoshita, Tatsunori Iwamura, Shin-ichi Watanabe, Tadashi Kataoka, Osamu Muraoka, Genzoh Tanabe, CHEMISTRY-A EUROPEAN JOURNAL, CHEMISTRY-A EUROPEAN JOURNAL, 12(14), 3896 - 3904, May 2006
    Summary:Reactions between chiral 3-cinnamoyl-4-methyl-5-phenyl-1,3-oxazolidine-2-thiones and aromatic aldehydes in the presence of BF3 center dot Et2O diastereoselectively produced tricyclic compounds incorporating a bridgehead carbon bound to four heteroatoms in high yields. Four stereocenters were induced during the reaction. The tricyclic products were transformed into propane-1,3-diols bearing three consecutive stereocenters by acid hydrolysis, S-methylation, and reductive removal of the chiral auxiliary.
  • Synthesis of 3-sulfanylpropanols containing three consecutive stereocenters via tandem Michael-aldol reaction of enoylthioamides with acetals as key reaction, H Kinoshita, N Takahashi, T Iwamura, S Watanabe, T Kataoka, O Muraoka, G Tanabe, TETRAHEDRON LETTERS, TETRAHEDRON LETTERS, 46(42), 7155 - 7158, Oct. 2005 , Refereed
    Summary:(2S,3S,1'R)-2-(alpha-Methoxybenzyl)-3-phenyl-3-sulfanylpropionamides were diastereoselectively prepared by the reactions of N-cinnamoyl-4S-isopropyl-5,5-dimethyloxazolidinethione with acetals in the presence of SnCl4. The absolute configuration of the three newly created contiguous stereocenters was determined by the X-ray analysis of the disulfide. The amides were transformed into propanols by the reductive removal of the oxazolidinone moiety. (c) 2005 Elsevier Ltd. All rights reserved.
  • Concise synthesis of the tricyclic skeleton of cylindricines using a radical cascade involving 6-Endo selective cyclization, T Taniguchi, O Tamura, M Uchiyama, O Muraoka, G Tanabe, H Ishibashi, SYNLETT, SYNLETT, 70(5)(7), 1179 - 1181, May 2005 , Refereed
    Summary:On treatment with Bu3SnH and azobis(cyclohexanecarbonitrile) (ACN), enamide 19 underwent a 6-endo-trig/5-endo-trig radical cascade to afford perhydropyrrolo[2.1-j]quinoline derivative 21, a cylindricine skeleton.
  • 7-endo selective aryl radical cyclization onto enamides leading to 3-benzazepines: Concise construction of a cephalotaxine skeleton, T Taniguchi, A Ishita, M Uchiyama, O Tamura, O Muraoka, G Tanabe, H Ishibashi, JOURNAL OF ORGANIC CHEMISTRY, JOURNAL OF ORGANIC CHEMISTRY, 70(5), 1922 - 1925, Mar. 2005 , Refereed
    Summary:Bu3SnH-mediated radical cyclizations of 2-(2-bromophenyl)N-ethenylacetamide gave 6-exo cyclization product 15 as the major product, whereas N-[2-(2-bromophenyl)ethyl]-N-ethenylamides gave almost exclusively 7-endo cyclization products. These results indicated that the position of the carbonyl group on enamide played an important role in deciding the course of the cyclization. The 7-endo selective cyclization was applied to concise construction of a cephalotaxine skeleton.
  • Development of novel diastereoselective alkenylation of enolates using alkenylselenonium salts, S Watanabe, T Ikeda, T Kataoka, G Tanabe, O Muraoka, ORGANIC LETTERS, ORGANIC LETTERS, 5(4), 565 - 567, Feb. 2003 , Refereed
    Summary:[GRAPHICS] A novel alkenylation of enolates using alkenylselenonium salts is described. A reaction of lithium enolates, which were prepared in situ by the reaction of LiHMDS and carbonyl compounds, with alkenylselenonium salts gave the ethenylation products of carbonyl compounds in high yield. Diastereoselective alkenylation was also accomplished by the reaction of the enolates derived from N-acyl-1,3-oxazolidin-2-ones with the alkenylselenonium salt to afford good results (up to 92% yield and up to 95% de).
  • Asymmetric induction of three consecutive chiral centers by reactions of N-enoylthioamides with aldehydes, T Kataoka, H Kinoshita, S Kinoshita, T Osamura, S Watanabe, T Iwamura, O Muraoka, G Tanabe, ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 42(25), 2889 - 2891, 2003 , Refereed
  • Potential antitumor-promoting diterpenes from the cones of Pinus luchuensis, T Minami, S Wada, H Tokuda, G Tanabe, O Muraoka, R Tanaka, JOURNAL OF NATURAL PRODUCTS, JOURNAL OF NATURAL PRODUCTS, 65(12), 1921 - 1923, Dec. 2002 , Refereed
    Summary:A new nor-labdane-type diterpene, 15-nor-labda-8(17),12E-dien-13,19-dienoic acid (1), along with five known diterpenes, 15-nor-14-oxolabda-8(17),12E-dien-19-oic acid (2), trans-communic acid (3), sandaracopimaric acid (4), dehydroabietic acid (5), and abieta-8,11,13-triene-15,18-diol (6), was isolated from the cones of Pinus luchuensis. The structure of 1 was established by chemical and spectroscopic methods. Among these isolates, compounds 2, 4, and 6 showed potent inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) activation induced by the tumor promoter 12-O-tetradecanoylphorbol 13-acetate.
  • The first isolation and characterization of sulfonylbuta-1,3-diynes, M Yoshimatsu, K Oh-Ishi, G Tanabe, O Muraoka, JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 1, JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 1, 1413-1416(12), 1413 - 1416, 2002 , Refereed
    Summary:We have isolated the sulfonylbuta-1,3-diynes 3 and 5 as colorless prisms, which demonstrate unprecedented dimerization. Furthermore, the reactions of 3 and 5 with alkoxides or buta-1,3-dienes were examined and the products obtained were either sulfonyl-beta-alkoxybut-1-en-3-ynes 16a-e, beta-alkoxybut-3-en-1-ynes 17a-d or the cycloadducts 23 and 24a, b.
  • [4(+)+2]-type polar cycloadditions of 2-benzothiopyrylium salt with alkenes, H Shimizu, N Araki, O Muraoka, G Tanabe, TETRAHEDRON LETTERS, TETRAHEDRON LETTERS, 41(13), 2161 - 2164, Mar. 2000 , Refereed
    Summary:Treatment of 2-benzothiopyrylium salt with alkenes such as styrene, p-methylstyrene, p-methoxystyrene, alpha-methylstyrene, and trans-anethole afforded the corresponding [4(+)+2]-type polar cycloaddition products, respectively. The structures of the cycloadducts were confirmed by X-ray crystal structure determination of the corresponding sulfone derivative. (C) 2000 Elsevier Science Ltd. All rights reserved.
  • A new fluoride-mediated 1,2-sulfonyl shift on cyclopropane, M Yoshimatsu, K Konishi, G Tanabe, O Muraoka, TETRAHEDRON LETTERS, TETRAHEDRON LETTERS, 39(13), 1781 - 1782, Mar. 1998 , Refereed
    Summary:A 1,2-sulfonyl shift reaction on cyclopropane proceeded during the reactions of 2-alkynyl-1a-e, 2-aryl-1,1-bis(sulfonyl)cyclopropanes 1f,1j-k and Bu4NF to give trans-1,2-bis(sulfonyl)cyclopropanes 2a-e, 2f, 2J-k. (C) 1998 Elsevier Science Ltd. All rights reserved.
  • Salacinol, potent antidiabetic principle with unique thiosugar sulfonium sulfate structure from the ayurvedic traditional medicine Salacia reticulata in Sri Lanka and India, M Yoshikawa, T Murakami, H Shimada, H Matsuda, J Yamahara, G Tanabe, O Muraoka, TETRAHEDRON LETTERS, TETRAHEDRON LETTERS, 38(48), 8367 - 8370, Dec. 1997 , Refereed
    Summary:A most potent natural alpha-glucosidase inhibitor named salacinol has been isolated from an antidiabetic Ayurvedic traditional medicine, Salacia reticulata WIGHT, through bioassay-guided separation. The stereostructure of salacinol was determined on the basis of chemical and physicochemical evidence, which included the X-ray crystallographic analysis, and the molecular conformation showed the unique spiro-like configuration of the inner salt comprised of 1-deoxy-4-thioarabinofuranosyl cation and 1'-deoxyerythrosyl-3'-sulfate anion. (C) 1997 Elsevier Science Ltd.
  • A regioselective addition reaction of a sulfonyl radical to conjugate enynesulfones: A convenient synthesis of 1,4-bis(arylsulfonyl)-1,3-butadiene, M Yoshimatsu, M Hayashi, G Tanabe, O Muraoka, TETRAHEDRON LETTERS, TETRAHEDRON LETTERS, 37(24), 4161 - 4164, Jun. 1996 , Refereed
    Summary:p-Tolyl benzeneselenosulfonate regioselectively added to the conjugate enynesulfones 1-9 gave (1E, 3E)-1,4-bis(arylsulfonyl)-1,3-butadienes 10-17, which were converted to the 4-hetero atom-substituted-1-phenylsulfonyl-1,3-butadienes 18, 21 and 22. (C) 1996 Elsevier Science Ltd

Conference Activities & Talks

  • Facile Synthesis of Neokotalanol, a Potent α-Glycosidase Inhibitor Isolated from the Ayurvedic Traditional Medicine “Salacia”, G. Tanabe, S. Ueda, K. Kurimoto, N. Sonoda, S. Marumoto, F. Ishikawa, O. Muraoka,   2019 09
  • An engineered aryl acid adenylation domain with an enlarged substrate binding pocket,   2019 09
  • A reprogrammed aryl acid adenylation domain with an enlarged substrate binding site,   2019 09
  • Reprogramming aryl acid adenylation domains for non-native building block, F. Ishikawa, A. Miyanaga, H. Kitayama, F. Kudo, T. Eguchi, G. Tanabe,   2019 08
  • An engineered aryl acid adenylating enzyme with a capacious active site microenvironment,   2019 06
  • Reprogramming aryl acid adenylating enzymes for non-native building blocks, Fumihiro Ishikawa, Hinano Kitayama, Genzoh Tanabe, 10th International Peptide Symposium (10th IPS),   2018 12
  • Antidiabetic Effects of Naturally Occurring Thiosugar Sulfoniums, Neokotalanol and Salacinol, from Salacia Genus Plants, T. Morikawa, M. Kobayashi, J. Akaki, K. Ninomiya, O. Muraoka, G. Tanabe, 28th International Symposium on the Organic Chemistry of Sulfur (ISOCS-28),   2018 08
  • Highly Diastereoselective Synthesis of Salacinol-type α-Glucosidase Inhibitors and Evaluation of Their in vivo α-Glucosidase Inhibitory Activity, TANABE Genzoh, 28th International Symposium on the Organic Chemistry of Sulfur (ISOCS-28),   2018 08
  • 7. Kazuki Matsuura, Ryosuke Satoh, Kanako Hagihara, Nozomu Tsuchimoto, Yoshimasa Hyodo, Ayako Kita, Genzoh Tanabe, Osamu Muraoka, Reiko Sugiura, TANABE Genzoh,   2016 10
  • Anticancer-drug screening utilizing fission yeast genetics identified Acremomannolipin A, a Calcium signalling modulator with anti-tumor activity, TANABE Genzoh,   2016 10
  • キラルテルリドの合成とエナンチオ選択的シクロプロパン化反応への応用, YAMAOKA NAKI, YOKOI RINA, WATANABE SHIN'ICHI, TANABE GENZO, MURAOKA OSAMU, 日本薬学会第 135 年会,   2015 03
  • バンレイシ科植物,Hornschuchia obliqua由来4,5‐didehydroguadiscineの合成およびそのメラニン形成抑制活性評価, TANABE GENZO, SHIRATO MIKI, KANNO YUTA, MORIKAWA TOSHIO, NINOMIYA KIYOFUMI, TSUTSUI NOZOMI, MURAOKA OSAMU, 日本薬学会第 135 年会,   2015 03
  • アーユルベーダ天然薬物“サラシア”由来α‐グルコシダーゼ阻害剤,neoponkoranolの新規ジアステレオ選択的合成, TANABE GENZO, SHIDA TOMOYUKI, MATSUMOTO HIROAKI, TSUTSUI NOZOMI, MURAOKA OSAMU, 日本薬学会第 135 年会,   2015 03
  • メース(Myristica fragrans,仮種皮)の機能性成分(5)―新規ジアリルノナノイド‐ネオリグナン付加体成分の化学構造―, MORIKAWA TOSHIO, YAWATA IKUKO, NINOMIYA KIYOFUMI, HAYAKAWA TAKAO, TANABE GENZO, MURAOKA OSAMU, 日本薬学会第 135 年会,   2015 03
  • サラシア属植物のα‐グルコシダーゼ阻害活性成分を指標とした品質評価, MORIKAWA TOSHIO, AKAKI JUNJI, NINOMIYA KIYOFUMI, TANABE GENZO, YOSHIKAWA MASAYUKI, MURAOKA OSAMU, 生薬分析シンポジウム講演要旨,   2014 11 07
  • インニトリル類とReformatsky反応剤の触媒的[6+1]付加環化反応を利用した含窒素ヘテロ環構築法の開発, TANAKA MIKI, TAKAHASHI NAMI, TANABE GENZO, MURAOKA OSAMU, YOSHIMATSU, MITSUHIRO, 有機合成シンポジウム,   2014 11
  • アーユルベーダ天然薬物“サラシア”由来salacinolをシードとするα‐グルコシダーゼ阻害剤のin silico設計,合成及びin vivo評価, TANABE GENZO, MATSUDA YUYA, TSUTSUI NOZOMI, MORIKAWA TOSHIO, AKAKI JUNJI, NINOMIYA KIYOFUMI, NAKANISHI ISAO, NAKAMURA SHIN'YA, YOSHIKAWA MASAYUKI, MURAOKA OSAMU, 天然薬物の開発と応用シンポジウム,   2014 11
  • サラシア属植物含有α‐グルコシダーゼ阻害活性成分salacinolおよびその類縁体の食後過血糖改善作用, MORIKAWA TOSHIO, AKAKI JUNJI, NINOMIYA KIYOFUMI, KINOUCHI ERI, TANABE GENZO, NAKANISHI ISAO, NAKAMURA SHIN'YA, YOSHIKAWA MASAYUKI, MURAOKA OSAMU, 天然薬物の開発と応用シンポジウム,   2014 11
  • 新規calciumシグナル調節物質acremomannolipin Aの構造活性相関:糖アルコール側鎖部の構造が活性に及ぼす効果, TSUTSUI NOZOMI, TANABE GENZO, GOTO GENKI, MORITA NAO, NOMURA NAOHISA, OKAYAMA YOSHITOMO, KITA AYAKO, SUGIURA REIKO, MURAOKA OSAMU, メディシナルケミストリーシンポジウム,   2014 11
  • Developement of a New Facile Route to Sulfonium Salts, a New Class of α-Glucosidase Inhibitors Isolated from Ayurvedic Medicine “Salacia”, TANABE Genzoh, 24th French-Japanese Symposium on Medicinal and Fine Chemistry,   2014 09
  • α‐グルコシダーゼ阻害活性物質salacinolおよびその誘導体の血糖値上昇抑制活性, MORIKAWA TOSHIO, KIUCHI ERI, AKAKI JUNJI, NINOMIYA KIYOFUMI, TANABE GENZO, NAKANISHI ISAO, NAKAMURA SHIN'YA, YOSHIKAWA MASAYUKI, MURAOKA OSAMU, 第61回 日本生薬学会年会,   2014 09
  • Salacinol and related analogs, new leads for type 2 diabetes therapeutic candidates from Thai traditional natural medicine, Salacia chinensis, Toshio Morikawa, Junji Akaki, Kiyofumi Ninomiya, Eri Kinouchi, Genzoh Tanabe, Masayuki Yoshikawa, Osamu Muraoka,   2014 05

Research Grants & Projects

  • Synthetic Studies on Pharmacologically Active Adamantane Derivatives by Use of the Bicyclo[3.3.1]nonane System as a Synthon
  • Studies on the Reactivity Reactivity of Tetra-n-butylammonium Hypophosphite as the New Reductant
  • Studies on Potent Antidiabetic Principle from the Ayurvedic Traditional Medicine Kotala himbutu(Salacia recticulata WIGHT)in Sri Lanka and India