論文 - 花屋　賢悟

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 （Asian Journal of Organic Chemistry）  10 （ 3 ） 582 - 587 2020年12月

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  21935807

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© 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.

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Copper-mediated peptide arylation selective for the N-terminus

Miller M.K., Wang H., Hanaya K., Zhang O., Berlaga A., Ball Z.T.

Chemical Science （Chemical Science）  11 （ 38 ） 10501 - 10505 2020年09月

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  20416520

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© The Royal Society of Chemistry 2020. Polypeptides present remarkable selectivity challenges for chemical methods. Amino groups are ubiquitous in polypeptide structure, yet few paradigms exist for reactivity and selectivity in arylation of amine groups. This communication describes the utilization of boronic acid reagents bearing certaino-electron withdrawing groups for copper-mediated amine arylation of the N-terminus under mild conditions and primarily aqueous solvent. The method adds to the toolkit of boronic acid reagents for polypeptide modification under mild conditions in water that shows complete selectivity for the N-terminus in the presence of lysine side chains.

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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 （Bioscience, Biotechnology and Biochemistry）  84 （ 8 ） 1554 - 1559 2020年08月

研究論文（学術雑誌）, 査読有り,  ISSN  09168451

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© 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).

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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 （Bioscience, Biotechnology and Biochemistry）  84 （ 7 ） 1339 - 1344 2020年07月

研究論文（学術雑誌）, 査読有り,  ISSN  09168451

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© 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.

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Accumulation of major linezolid metabolites in patients with renal impairment

Souza E., Crass R.L., Felton J., Hanaya K., Pai M.P.

Antimicrobial Agents and Chemotherapy （Antimicrobial Agents and Chemotherapy）  64 （ 5 ）  2020年05月

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  00664804

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© 2020 American Society for Microbiology. All Rights Reserved. In patients with renal impairment (n=22 of 39), the median serum concentrations of linezolid, PNU-142300, and PNU-142586 were 1.6-, 3.3-, 2.8-fold higher, respectively, than in patients without renal impairment. Metabolite concentrations in paired samples were poorly correlated with linezolid concentrations (r2 = 0.26 for PNU-142300 and 0.06 for PNU-142586). Linezolid and its metabolites share potential toxicophores that deserve characterization to mitigate higher myelosuppression risk in patients with renal impairment.

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Stepwise approach for sterically hindered C<inf>sp³</inf>-C<inf>sp³</inf> 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 （Chemical Communications）  56 （ 25 ） 3621 - 3624 2020年03月

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  13597345

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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.

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Development of a sensitive LC–MS/MS method for quantification of linezolid and its primary metabolites in human serum

Souza E., Felton J., Crass R., Hanaya K., Pai M.

Journal of Pharmaceutical and Biomedical Analysis （Journal of Pharmaceutical and Biomedical Analysis）  178 2020年01月

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  07317085

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© 2019 Elsevier B.V. Linezolid (LZD) is a widely used antimicrobial that is active against a broad range of disease-causing bacteria. Myelosuppression is major treatment-limiting toxicity of LZD that occurs more frequently in patients with renal insufficiency. Quantification of LZD and its two primary metabolites (PNU-142300 and PNU-142586), which undergo significant renal elimination, may support design of improved dosing strategies to mitigate the risk of myelosuppression. In this study, we established the first liquid chromatography-tandem mass spectrometry (LC–MS/MS) method for the simultaneous quantification of LZD and its main metabolites in human serum. Proteins in serum samples were precipitated with acetonitrile containing a deuterated internal standard. Chromatographic separation of analytes was performed with Waters X-bridge column (C18, 150 × 4.6 mm, 3.5 μm) at 25 °C and subjected to mass analysis using positive electro-spray ionization. The mobile phase A was water with 0.1% formic acid, and mobile phase B was acetonitrile with 0.1% formic acid at a flow rate of 0.6 mL/min, within a 15 min run time. Standard curves were linear and correlation coefficients (r2) were ≥0.99 for concentration ranges of 0.1–50 μg/mL for LZD and PNU-142300, and 0.1–25 μg/mL for PNU-142586. The inter- and intra-assay precisions were <15% for all analytes in quality control samples, and the accuracies ranged from 97 to 112%. Extraction recoveries ranged from 78 to 103% for all analytes, and there was no significant matrix effect. Samples from 10 patients (5 with renal impairment) were assayed. Mean (SD) LZD, PNU-142300 and PNU-142586 trough concentrations were 19.4(6.8), 11.6(6.8), 25.7(16.4) μg/mL, respectively, in patients with renal impairment. These values were 2.5-, 5.8-, and 6.8-fold higher for LZD, PNU-142300 and PNU-142586, respectively compared to patients without renal impairment. The method was effectively applied in the determination of LZD and its main metabolites in human serum.

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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 （Heterocycles）  100 （ 1 ） 129 - 136 2020年

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  03855414

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© 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.

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Analysis of Interconversion between Atropisomers of Chiral Substituted 9,9’-Bicarbazole

Kobayashi T., Ishiwari F., Fukushima T., Hanaya K., Sugai T., Higashibayashi S.

European Journal of Organic Chemistry （European Journal of Organic Chemistry）  2021 （ 3 ） 449 - 451 2020年

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  1434193X

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© 2020 Wiley-VCH GmbH Interconversion of atropisomers of chiral 3,3’-di-tert-butyl-9,9’-bicarbazole linked by a single N−N bond was analyzed by DFT calculations and experiments. The calculations revealed that the trans transition state has a lower energy for the interconversion than the cis transition state. The lowest transition state of interconversion between natural dixiamycins A and B containing a 9,9’-bicarbazole structure was found to be the trans transition state. The calculations also indicated that degradation through N−N bond cleavage was faster than racemization. Atropisomeric enantiomers of 3,3’-di-tert-butyl-9,9’-bicarbazole were resolved by chiral HPLC for the first time, and then racemization and N−N bond cleavage were investigated by heating experiments, showing that racemization did not take place below the degradation temperature.

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Nickel(II)-promoted amide N-H arylation of pyroglutamate-histidine with arylboronic acid reagents

Hanaya K., Miller M., Ball Z.

Organic Letters （Organic Letters）  21 （ 7 ） 2445 - 2448 2019年04月

研究論文（学術雑誌）, 共著, 筆頭著者, 査読有り,  ISSN  15237060

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© 2019 American Chemical Society. Small and simple bioorthogonal reactive handles that can be readily encoded by natural processes are important for bioconjugation. A rapid nickel-promoted N-H arylation of pyroglutamate-histidine sequences with 2-nitroarylboronic acids proceeds under mild aqueous conditions. Chemoselective activation of a lactam amide N-H within a peptide or protein provides a new approach to selective conjugation in polyamide structures.

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Rapid nickel(ii)-promoted cysteine: S -arylation with arylboronic acids

Hanaya K., Ohata J., Miller M., Mangubat-Medina A., Swierczynski M., Yang D., Rosenthal R., Popp B., Ball Z.

Chemical Communications （Chemical Communications）  55 （ 19 ） 2841 - 2844 2019年02月

研究論文（学術雑誌）, 査読有り,  ISSN  13597345

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© 2019 The Royal Society of Chemistry. S-Arylation of cysteine residues is an increasingly powerful tool for site-specific modification of proteins, providing novel structure and electronic perturbation. The present work demonstrates an operationally-simple cysteine arylation reaction 2-nitro-substituted arylboronic acids, promoted by a simple nickel(ii) salt. The process exhibits strikingly fast reaction rates under physiological conditions in purely aqueous media with excellent selectivity toward cysteine residues. Cysteine arylation of natural proteins and peptides allows attachment of useful reactive handles for stapling, imaging, or further conjugation.

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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 （ChemBioChem）  20 （ 2 ） 210 - 220 2019年01月

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  14394227

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© 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.

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Syntheses of Englerin A, a Potent Renal Cancer Inhibitor

Hagihara S., Hanaya K., Sugai T., Shoji M.

Asian Journal of Organic Chemistry （Asian Journal of Organic Chemistry）  8 （ 1 ） 48 - 62 2019年01月

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  21935807

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© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Mankind has been searching for anticancer drugs from nature and artificial compounds. Since the discovery of englerin A, a guaiane sesquiterpene possessing the characteristic tricyclic 5–6-5 fused ring framework with contiguous seven stereogenic centers and isolated from Phyllanthus engleri, many synthetic groups have enthusiastically launched and accomplished its the chemical synthesis. All the synthetic groups focused on how to efficiently construct the tricyclic framework containing oxygen bridge with various approaches. In this review, the total and formal syntheses of englerin A reported to date are summarized.

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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 （Heterocycles）  99 （ 1 ） 638 - 648 2019年

ISSN  03855414

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© 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.

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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年

ISSN  03855414

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© 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.

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

ISSN  09168451

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© 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.

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

Shindo Y., Nomura S., Saikawa Y., Nakata M., Tanaka K., Hanaya K., Sugai T., Higashibayashi S.

Asian Journal of Organic Chemistry （Asian Journal of Organic Chemistry）  7 （ 9 ） 1797 - 1801 2018年09月

ISSN  21935807

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© 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.

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Recent examples of the use of biocatalysts with high accessibility and availability in natural product synthesis

Sugai T., Higashibayashi S., Hanaya K.

Tetrahedron （Tetrahedron）  74 （ 27 ） 3469 - 3487 2018年07月

ISSN  00404020

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© 2018 Elsevier Ltd Utilization of biocatalysts with high accessibility and availability, which have recently been applied in the preparation of enantiomerically enriched starting materials and synthetic intermediates for natural product syntheses (mainly 2013–2017) are summarized in this review. The main contents are as follows: 1) recruitment of biocatalysts for the transformation of organic compounds; 2) special precautions for preparative-scale biocatalytic synthetic experiments; 3) asymmetric reduction of carbonyl substrates; 4) kinetic resolution of alcohol and carboxylate enantiomers; 5) desymmetrization of multifunctional alcohol and carboxylate substrates; and 6) recognition of remote and non-central chirality.

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A Vinylogous Photocleavage Strategy Allows Direct Photocaging of Backbone Amide Structure

Mangubat-Medina A., Martin S., Hanaya K., Ball Z.

Journal of the American Chemical Society （Journal of the American Chemical Society）  140 （ 27 ） 8401 - 8404 2018年06月

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  00027863

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© 2018 American Chemical Society. Side-chain modifications that respond to external stimuli provide a convenient approach to control macromolecular structure and function. Responsive modification of backbone amide structure represents a direct and powerful alternative to impact folding and function. Here, we describe a new photocaging method using histidine-directed backbone modification to selectively modify peptides and proteins at the amide N-H bond. A new vinylogous photocleavage method allows photorelease of the backbone modification and, with it, restoration of function.

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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 （Tetrahedron）  74 （ 7 ） 740 - 745 2018年02月

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  00404020

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© 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.

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