Details of a Researcher - Higashibayashi, Shuhei

Papers - Higashibayashi, Shuhei

Division display 21 - 40 of about 108 ／ All the affair displays >>

Semisynthesis of prunetin, a bioactive O-methylated isoflavone from naringenin, by the sequential deacetylation of chalcone intermediates and oxidative rearrangement

Sugai T., Hanaya K., Higashibayashi S.

Bioscience, biotechnology, and biochemistry 85 ( 1 ) 143 - 147 2021.01

Research paper (scientific journal), Joint Work, Accepted

Access to Document (DOI)

A Concise Total Synthesis of Dehydroantofine and Its Antimalarial Activity against Chloroquine-Resistant Plasmodium falciparum

Yamasaki N., Iwasaki I., Sakumi K., Hokari R., Ishiyama A., Iwatsuki M., Nakahara M., Higashibayashi S., Sugai T., Imagawa H., Kubo M., Fukuyama Y., Ōmura S., Yamamoto H.

Chemistry - A European Journal 27 5555 - 5563 2021

Research paper (scientific journal), Joint Work, Accepted, ISSN 09476539

Access to Document (DOI)

Nickel(II)-Mediated C−S Cross-Coupling Between Thiols and ortho-Substituted Arylboronic Acid

Hanaya K., Ohtsu H., Kawano M., Higashibayashi S., Sugai T.

Asian Journal of Organic Chemistry 10 ( 3 ) 582 - 587 2021

Research paper (scientific journal), Joint Work, Accepted, ISSN 21935807

© 2020 Wiley-VCH GmbH Herein, we report a C−S cross-coupling reaction between alkyl thiols or aryl thiols and ortho-substituted arylboronic acids that proceeds in the presence of an inexpensive and ligand-free NiCl2 ⋅ 6H2O salt and N-methylmorpholine, a weak base, at 25 °C in air. The presence of coordinating and electron-withdrawing groups at the ortho-position of the arylboronic acids played a crucial role in determining the efficiency of the reaction. X-ray crystallographic analysis revealed that the [NiCl2(DMF)2(H2O)2] complex was formed in-situ. The complex is an excellent precursor of the active nickel species. The reaction offers an extremely mild and operationally convenient method to access a wide variety of alkyl aryl sulfides and diaryl sulfides without using expensive transition metals, such as palladium, gold, and rhodium, and specialized and expensive ligands.

Access to Document (DOI)

Theoretical Analysis of the Heterocyclic [4+2] Cycloaddition Between Pyridinium Ion and Enol Ether

Nakahara M., Hanaya K., Sugai T., Higashibayashi S.

ChemistryOpen 2021

Research paper (scientific journal), Joint Work, Accepted

© 2021 The Authors. Published by Wiley-VCH GmbH Dearomative heterocyclic [4+2] cycloaddition between the N-(2,4-dinitrophenyl)pyridinium ion of nicotinamide and an enol ether was analyzed by Density Functional Theory (DFT) calculations. The calculation revealed that the reaction undergoes stepwise bond formation rather than occurring in a concerted manner. The experimental products were found to be both kinetically and thermodynamically favored. The calculated transition states and intermediate suggested that the high diastereoselectivity is derived from the electrostatic interaction between the 2-nitro group of the pyridinium ion and the hydrogen of the enol ether.

Access to Document (DOI)

Improved preparation of vitexin from hot water extract of Basella alba, the commercially available vegetable Malabar spinach (“Tsurumurasaki” in Japanese) and the application to semisynthesis of chafuroside B

Kurahayashi K., Hanaya K., Higashibayashi S., Sugai T.

Bioscience, Biotechnology and Biochemistry 84 ( 8 ) 1554 - 1559 2020.08

Research paper (scientific journal), Joint Work, Accepted, ISSN 09168451

© 2020, © 2020 Japan Society for Bioscience, Biotechnology, and Agrochemistry. Hot water extraction of D-arabinofuranosylvitexin from the raw leaves of commercially available Basella alba “Tsurumurasaki” and subsequent acidic hydrolysis was improved to be a procedure using a high-pressure steam sterilizer to afford vitexin. The amount was estimated to be 14.1 mg from 1 g of dry weight of the raw leaves, whose recovery was calculated to be 95% based on the estimated content of D-arabinofuranosylvitexin in B. alba raw leaves. The product was dehydratively cyclized between hydroxy groups on the carbohydrate and flavone skeletons under modified Mitsunobu reaction conditions in N,N-dimethylformamide to give chafuroside B, which is known to be a bioactive Oolong tea polyphenol. Through these transformations, 10.2 mg of chafuroside B could be semisynthesized from 1 g of dry weight of the raw leaves, and the efficiency was improved compared to that from the extraction from Oolong tea (3.4 μg from 1 g of dry weight).

Access to Document (DOI)

Comprehensive semisyntheses of catathelasmols C, D, and E from D-glutamic acid, utilizing lipase-catalyzed site-selective reactions on intermediates

Hashiba R., Hashimoto R., Nishiguchi M., Kobayashi T., Hanaya K., Higashibayashi S., Sugai T.

Bioscience, Biotechnology and Biochemistry 84 ( 7 ) 1339 - 1344 2020.07

Research paper (scientific journal), Joint Work, Accepted, ISSN 09168451

© 2020, © 2020 Japan Society for Bioscience, Biotechnology, and Agrochemistry. Catathelasmols C, D, and E, which had been isolated from Catathelasma imperiale as inhibitors for 11-hydroxysteroid dehydrogenases, were comprehensively semisynthesized from commercially available D-glutamic acid. The key synthetic intermediate, (R)-pentane-1,2,5-triol, was site-selectively acetylated by treatment with vinyl acetate and Candida antarctica lipase B (Novozym 435) in tetrahydrofuran (THF) at 25°C to furnish 1,5-diacetate (catathelasmol E, quantitative). The acetylation occurred site-selectively on the primary alcohols at the C-1 and C-5 positions over the secondary alcohol at the C-2 position. Dichromic acid oxidation provided 2-oxopentane-1,5-diyl diacetate (catathelasmol C, 78%). Burkholderia cepacia lipase-catalyzed transesterification with methanol in THF at–5°C proceeded preferentially on the acetate at C-1 located adjacent to the C-2 carbonyl group over the other terminal acetate at the C-5 position. 5-Hydroxy-4-oxopentyl acetate (catathelasmol D) was obtained in 53% yield.

Access to Document (DOI)

Stepwise approach for sterically hindered Csp3-Csp3 bond formation by dehydrogenative: O -alkylation and Lewis acid-catalyzed [1,3]-rearrangement towards the arylalkylcyclopentane skeleton of sesquiterpenes

Fujitani B., Hanaya K., Sugai T., Higashibayashi S.

Chemical Communications 56 ( 25 ) 3621 - 3624 2020.03

Research paper (scientific journal), Joint Work, Accepted, ISSN 13597345

This journal is © The Royal Society of Chemistry. A stepwise dehydrogenative cross-coupling method was developed for the formation of sterically hindered Csp3-Csp3 bonds. Intramolecular dehydrogenative O-alkylation of a β-ketoester by 2,3-dichloro-5,6-dicyano-p-benzoquinone to form an oxolane followed by Lewis acid-catalyzed [1,3]-rearrangement furnished the sesquiterpene arylmethylcyclopentane skeleton. The formal syntheses of herbertane-type β-herbertenol, cuparane-type enokipodins A and B were also achieved.

Access to Document (DOI)

Syntheses of indirubins by aldol condensation of isatins with indoxyl anion generated in situ by lipase-catalyzed deacetylation of indoxyl acetate

Sugai T., Hanaya K., Higashibayashi S.

Heterocycles 100 ( 1 ) 129 - 136 2020

Research paper (scientific journal), Joint Work, Accepted, ISSN 03855414

© 2020 The Japan Institute of Heterocyclic Chemistry. The syntheses of indirubin (76% yield), 6-bromoindirubin (82% yield), and 6-bromoindirubin-3′-oxime (78% yield in two steps) were achieved via the lipase-triggered aldol condensation between isatins and an indoxyl anion in tetrahydrofuran under anhydrous and anaerobic conditions as the key step. The aldol donor was generated in situ by Burkholderia cepacia lipase (Amano PS-IM)-catalyzed deacetylation of commercially available and stable indoxyl acetate in the presence of triethylamine and with 2-propanol as the transesterification reagent. The scale-up of the presently developed reactions is easier than that in the previously reported chemical aldol condensations, because of the simplicity of the isolation procedure and suppression of the oxidative byproduct formation from indoxyl acetate.

Access to Document (DOI)

Synthesis of 5-Hydroxy-3′,4′,7-trimethoxyflavone and Related Compounds and Elucidation of Their Reversal Effects on BCRP/ABCG2-Mediated Anticancer Drug Resistance

Tsunekawa R., Katayama K., Hanaya K., Higashibayashi S., Sugimoto Y., Sugai T.

ChemBioChem 20 ( 2 ) 210 - 220 2019.01

Research paper (scientific journal), Joint Work, Accepted, ISSN 14394227

© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim 3′,4′,7-Trimethoxyflavone (TMF) has been reported to show a potent reversal effect on drug resistance mediated by breast cancer resistance protein (BCRP)/ATP-binding cassette subfamily G member 2 (ABCG2). In this study, we designed and synthesized five derivatives with either a hydroxy group or a fluorine atom at C-5 and several kinds of capping moiety at the C-7 hydroxy group, on the same 3′,4′-dimethoxy-substituted flavone skeleton. We subsequently evaluated the efficacies of these compounds against BCRP-expressing human leukaemia K562/BCRP cells. Reversal of drug resistance was expressed as the concentration of compound causing a twofold reduction in drug sensitivity (RI 50 ). Of the synthesized compounds, the reversal effect of 5-hydroxy-3′,4′,7-trimethoxyflavone (HTMF, RI 50 7.2 nm) towards 7-ethyl-10-hydroxycamptothecin (SN-38) was stronger than that of TMF (RI 50 18 nm). Fluoro-substituted 5-fluoro-3′,4′,7-trimethoxyflavone (FTMF, RI 50 25 nm) and monoglycosylated 7-(β-glucosyloxy)-5-hydroxy-3′,4′-dimethoxyflavone (GOHDMF, 91 nm) also exhibited reversal effects, whereas the di- and triglycoside derivatives did not. TMF, HTMF and FTMF at 0.01–10 μm upregulated the K562/BCRP cellular accumulation of Hoechst 33342 nuclear staining dye. In addition, western blotting revealed that treatment of K562/BCRP cells with 0.1 μm TMF, HTMF or FTMT suppressed the expression of BCRP. HTMF showed the strongest inhibition of BCRP-mediated efflux and suppression of BCRP expression of the three effective synthesized flavones.

Access to Document (DOI)

Site-selective synthesis of acacetin and genkwanin through lipase-catalyzed deacetylation of apigenin 5,7-diacetate and subsequent methylation

Fujita R., Mandal S., Hanaya K., Shoji M., Higashibayashi S., Sugai T.

Heterocycles 99 ( 1 ) 638 - 648 2019

Research paper (scientific journal), Joint Work, Accepted, ISSN 03855414

© 2019 The Japan Institute of Heterocyclic Chemistry. Candida antarctica lipase B-catalyzed deacetylation proceeded with high site-selectivity on the C-4′ acetyl group in apigenin triacetate to give apigenin 5,7-diacetate. Methylation of the liberated hydroxy group with the combination of trimethyloxonium tetrafluoroborate (Meerwein reagent) and 1,8-bis(dimethylamino)naphthalene (proton sponge) in CH2Cl2 proceeded in a quantitative manner to give the product methylated at the C-4′ hydroxy group (acacetin 5,7-diacetate). Even with the same precursor, a different methylation product at the C-7 hydroxy group (genkwanin 4′,5-diacetate) was obtained in 86% yield by applying iodomethane and Cs2CO3 in dimethyl sulfoxide (DMSO). The methylated products were deprotected to form acacetin and genkwanin. We inferred that the latter unexpected methylation was ascribable to the intermolecular migration of an acetyl group from C-7 to C-4′. DFT calculations indicated that the C-7 phenoxide ion was 12.6 kJ/mol more stable than the initially formed C-4′ phenoxide ion.

Access to Document (DOI)

Lipase-catalyzed site-selective deacetylation of sterically hindered naphthohydroquinone diacetate and its application to the synthesis of a heterocyclic natural product

Hashimoto R., Sakakura A., Hanaya K., Higashibayashi S., Sugai T.

Heterocycles (Heterocycles) 99 ( 1 ) 625 - 632 2019

Research paper (scientific journal), Joint Work, Accepted, ISSN 03855414

© 2019 The Japan Institute of Heterocyclic Chemistry. Lipase-catalyzed site-selective deacetylation of 2,5-dimethylnaphthalene-l,4-diol diacetate was examined. With Candida antarctica lipase B, the suppressing effect of a methyl substituent at the peri-position of the a-naphthyl ester over that at the ortho-position was significant. This site-selectivity was in contrast to that of chemical hydrolysis reported to date. From the resulting monoacetate, mansonone F, a physiologically active heterocyclic orthoquinone, was synthesized in 38% yield in as few as three steps.

Access to Document (DOI)

Chemoenzymatic synthesis of hydroxytyrosol monoesters and their suppression effect on nitric oxide production stimulated by lipopolysaccharides

Sakakura A., Pauze M., Namiki A., Funakoshi-Tago M., Tamura H., Hanaya K., Higashibayashi S., Sugai T.

Bioscience, Biotechnology and Biochemistry 83 ( 2 ) 185 - 191 2019

Research paper (scientific journal), Joint Work, Accepted, ISSN 09168451

© 2018 Japan Society for Bioscience, Biotechnology, and Agrochemistry. Fatty acid monoesters of hydroxytyrosol [2-(3,4-dihydroxyphenyl)ethanol] were synthesized in two steps from tyrosol (4-hydroxyphenylethanol) by successive Candida antarctica lipase B-catalyzed chemoselective acylation on the primary aliphatic hydroxy group over phenolic hydroxy group in tyrosol, and 2-iodoxybenzoic acid (IBX)-mediated hydroxylation adjacent to the remaining free phenolic hydroxy group. Examination of their suppression effects on nitric oxide production stimulated by lipopolysaccharides in RAW264.7 cells showed that hydroxytyrosol butyrate exhibited the highest inhibition (IC 50 7.0 μM) among the tested compounds.

Access to Document (DOI)

Dearomative Oxidative Rearrangement of [3]Cyclo-1,8-carbazolylene

Yasui, Masamichi, Ohtsu, Hiroyoshi, Kawano, Masaki, Hanaya, Kengo, Sugai, Takeshi, Higashibayashi, Shuhei

CHEMISTRY LETTERS 47 ( 11 ) 1357 - 1359 2018.11

Research paper (scientific journal), Joint Work, Accepted, ISSN 0366-7022

Access to Document (DOI)

Synthesis and Properties of Hydrazine-Embedded Biphenothiazines and Application of Hydrazine-Embedded Heterocyclic Compounds to Fluorescence Cell Imaging

Shindo, Yuri, Nomura, Shogo, Saikawa, Yoko, Nakata, Masaya, Tanaka, Katsunori, Hanaya, Kengo, Sugai, Takeshi, Higashibayashi, Shuhei

ASIAN JOURNAL OF ORGANIC CHEMISTRY 7 ( 9 ) 1797 - 1801 2018.09

Research paper (scientific journal), Joint Work, Accepted, ISSN 2193-5807

© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Hydrazine-embedded unsubstituted butterfly-shaped biphenothiazine and its sulfoxides were synthesized by dimerization of 1,9-dibromophenothiazine, which was prepared by realizing selective debromination at the 3,7-positions of 1,3,7,9-tetrabromophenothiazine. cis/trans-Biphenothiazine sulfoxide was selectively prepared by changing the oxidation temperature to control the inversion rate of the butterfly shape of the intermediate. Their butterfly-shapes, conformations, photophysical properties (UV-vis absorption, fluorescence), and redox properties were elucidated by X-ray analysis, DFT calculations, spectral and electrochemical measurements. Fluorescent hydrazine-embedded biphenothiazine sulfoxides and bicarbazoles were applied to cell imaging of HeLa cells. The bicarbazoles exhibited high fluorescence signals in the cells with low toxicity.

Access to Document (DOI)

Molecular Arrangements of Corannulene and Sumanene in Single-Walled Carbon Nanotubes

Iizumi, Yoko, Liu, Zheng, Suenaga, Kazu, Okada, Susumu, Higashibayashi, Shuhei, Sakurai, Hidehiro, Okazaki, Toshiya

CHEMNANOMAT 4 ( 6 ) 557 - 561 2018.06

Research paper (scientific journal), Joint Work, Accepted, ISSN 2199-692X

© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Molecular arrangements of bowl-shaped molecules, corannulene and sumanene, in single-walled carbon nanotubes (SWCNTs) were investigated using high-resolution transmission microscopy and near-infrared photoluminescence spectroscopy. The results indicated that corannulenes are nested in SWCNTs with a random orientation, whereas sumanenes form stacked structures. The trends are consistent with the molecular orientations of corannulene and sumanene in single crystals.

Access to Document (DOI)

Triazasumanene: An Isoelectronic Heteroanalogue of Sumanene

Tan, Qitao, Kaewmati, Patcharin, Higashibayashi, Shuhei, Kawano, Masaki, Yakiyama, Yumi, Sakurai, Hidehiro

BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 91 ( 4 ) 531 - 537 2018.04

Research paper (scientific journal), Joint Work, Accepted, ISSN 0009-2673

© 2018 The Chemical Society of Japan. Buckybowls, which are represented by sumanene and corannulene, have attracted considerable attention for their unique bowl structures and interesting physicochemical properties. However, still few heteroatom-doped buckybowls have been reported to date. Here we show the successful synthesis of triazasumanene, an isoelectronic heteroanalogue of sumanene, which possesses a deeper bowl with stable bowl chirality and unique helical columnar packing in the crystal as an enantiopure form. In contrast, the crystal packing of the racemate shows a unidirectional columnar structure, which resembles that of the pristine sumanene. Doping of nitrogen atoms into the periphery of the sumanene framework also leads to perturbations of the electronic structure as shown by a significant decrease of the lowest unoccupied molecular orbital (LUMO) level and the optical band gap in comparison to all-carbon sumanene. The pyridine ring of triazasumanene shows unusual susceptibility towards acidic hydrolysis due to the highly strained curved structure.

Access to Document (DOI)

Formal total synthesis of (−)-hamigeran B from a chemo-enzymatically prepared building block with quaternary chiral center

Kuwata K., Fujita R., Hanaya K., Higashibayashi S., Sugai T.

TETRAHEDRON 74 ( 7 ) 740 - 745 2018.02

Research paper (scientific journal), Joint Work, Accepted, ISSN 00404020

© 2017 Elsevier Ltd A formal total synthesis of (−)-hamigeran B was achieved in 17 steps from commercially available ethyl 2-oxocyclopentanecarboxylate. Carbonyl reductase-catalyzed asymmetric reduction and the subsequent chemical transformations furnished an enantiomerically pure synthetic intermediate, (R)-5-formyl-2-isopropyl-5-methylcyclopent-1-en-1-yl trifluoromethylsulfonate. Suzuki-Miyaura coupling with Gao's arylboronate [2-(2-formyl-3-methoxy-5-methylphenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane], under PdCl2(dppf)•CH2Cl2 catalysis, and the subsequent cyclization by way of intramolecular reductive SmI2-mediated 1,2-diol formation provided a tricyclic skeleton with a tetrasubstituted double bond between C-1 and C-9b. Upon hydrogenation of this double bond, the proper stereochemistry of the remaining chiral centers was established. Exclusive addition of the hydrogen atom from the β-face occurred, owing to the shielding of the α-face with a bulky TBS protective group on the C-4 alcohol. The hydrogenation products were transformed into Clive's synthetic precursor for (−)-hamigeran B.

Access to Document (DOI)

Chemoenzymatic approaches to the synthesis of the (1S,2R)-isomer of benzyl 2-hydroxycyclohexanecarboxylate

Ryuji Tsunekawa, Kengo Hanaya, Shuhei Higashibayashi, Mitsuru Shoji, Takeshi Sugai

MOLECULAR CATALYSIS 444 84 - 89 2018.01

Research paper (scientific journal), Joint Work, Accepted, ISSN 2468-8231

© 2017 Elsevier B.V. We examined ten strains of cultured whole-cell yeasts for the asymmetric reduction of commercially available ethyl 2-oxocyclohexanecarboxylate, and found that the (1S,2S)-stereoisomer of ethyl 2-hydroxycyclohexanecarboxylate was the major stereoisomer produced by Williopsis californica JCM 3600. The ethyl group of the ester was then substituted with a benzyl group with low volatility and increased hydrophobicity to facilitate the isolation of the expected product. Incubation with W. californica furnished benzyl (1S,2S)-2-hydroxycyclohexanecarboxylate (>99.9% ee) in 51.0% yield together with its (1R,2S)-isomer (>99.9% ee) in 35.4% yield. Upon treatment of the same substrate bearing the benzyl ester with a screening kit of purified overexpressed carbonyl reductases (Daicel Chiralscreen® OH), two enzymes (E031, E078) furnished the (1R,2S)-isomer as the major product. With another enzyme (E007), the (1S,2R)-isomer was obtained, but its ee was very low (25.6%). The highly enantiomerically enriched (1S,2S)-isomer obtained by W. californica was transformed to the (1S,2R)-isomer (>99.9% ee), whose availability until now has been low, in 43.3% yield over two steps involving tosylation and subsequent inversive attack with tetrabutylammonium nitrite.

Access to Document (DOI)

Application of Hydrazine-Embedded Heterocyclic Compounds to High Voltage Rechargeable Lithium Organic Batteries

Takeshi Shimizu, Koji Yamamoto, Palash Pandit, Hirofumi Yoshikawa, Shuhei Higashibayashi

SCIENTIFIC REPORTS 8 ( 1 ) 6417 - 6422 2018.01

Research paper (scientific journal), Joint Work, Accepted, ISSN 2045-2322

© 2018 The Author(s). Hydrazine-embedded heterocyclic compounds with dimeric dimethylacridine (1b), carbazole (2b), and phenothiazine (3b) skeletons were applied to cathode active materials of rechargeable lithium organic batteries, and the performance of the batteries was evaluated. The charge/discharge curves exhibited clear plateaus in the high voltage range of 3.3-3.7 V. The capacities of the plateau regions were comparable to the calculated capacities corresponding to the one-electron redox of the molecules. The amount of the active compound 3b could be increased up to 30 wt% in the electrode composite, and fast charge/discharge performance was also observed.

Access to Document (DOI)

Synthesis of trilobatin from naringin via prunin as the key intermediate: acidic hydrolysis of the -rhamnosidic linkage in naringin under improved conditions

Kurahayashi, Kazuki, Hanaya, Kengo, Higashibayashi, Shuhei, Sugai, Takeshi

BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY 82 ( 9 ) 1463 - 1467 2018

Research paper (scientific journal), Joint Work, Accepted, ISSN 0916-8451

Access to Document (DOI)

　 Previous page - Next page 　