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  1. Article ; Online: Asymmetric Synthesis of a Quaternary Carbon Stereogenic Center by Organocatalysis Using a Primary Amino Acid and Its Salt.

    Yoshida, Masanori

    Chemical record (New York, N.Y.)

    2023  Volume 23, Issue 7, Page(s) e202200276

    Abstract: In this personal account, our recent developments on the asymmetric synthesis of a quaternary carbon stereogenic center by organocatalysis using a primary amino acid and its salt as a catalyst are described in three chapters: (1) conjugate addition to ... ...

    Abstract In this personal account, our recent developments on the asymmetric synthesis of a quaternary carbon stereogenic center by organocatalysis using a primary amino acid and its salt as a catalyst are described in three chapters: (1) conjugate addition to nitroalkenes and vinyl ketones, (2) nucleophilic addition to π-allyl palladium complexes, and (3) nucleophilic substitution reactions with allyl and propargyl halides. By these methods, asymmetric α-allylation of α-branched aldehydes and ketones smoothly proceeded to give γ-nitroaldehydes, ketoaldehydes, α-allylated aldehydes, and α-allylated β-ketoesters possessing a quaternary carbon stereogenic center in good yields with high enantioselectivities.
    MeSH term(s) Carbon/chemistry ; Molecular Structure ; Stereoisomerism ; Aldehydes/chemistry ; Ketones/chemistry ; Amino Acids
    Chemical Substances Carbon (7440-44-0) ; Aldehydes ; Ketones ; Amino Acids
    Language English
    Publishing date 2023-02-02
    Publishing country United States
    Document type Journal Article ; Review
    ZDB-ID 2044646-9
    ISSN 1528-0691 ; 1527-8999
    ISSN (online) 1528-0691
    ISSN 1527-8999
    DOI 10.1002/tcr.202200276
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Organocatalytic Asymmetric α-Allylation and Propargylation of α-Branched Aldehydes with Alkyl Halides.

    Yoshida, Masanori

    The Journal of organic chemistry

    2021  Volume 86, Issue 15, Page(s) 10921–10927

    Abstract: Enantioselective α-allylation and -propargylation of α-branched aldehydes with alkyl halides was successfully performed using a chiral primary amino acid organocatalyst. This alkylation reaction, involving the generation of a chiral quaternary carbon ... ...

    Abstract Enantioselective α-allylation and -propargylation of α-branched aldehydes with alkyl halides was successfully performed using a chiral primary amino acid organocatalyst. This alkylation reaction, involving the generation of a chiral quaternary carbon stereocenter, proceeded smoothly in a mildly basic aqueous solution of potassium hydrogen carbonate to furnish α-allylated or -propargylated aldehydes in a good yield (up to 87%) and high enantioselectivity (up to 96% ee).
    MeSH term(s) Aldehydes ; Alkylation ; Amino Acids ; Carbon
    Chemical Substances Aldehydes ; Amino Acids ; Carbon (7440-44-0)
    Language English
    Publishing date 2021-07-15
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 123490-0
    ISSN 1520-6904 ; 0022-3263
    ISSN (online) 1520-6904
    ISSN 0022-3263
    DOI 10.1021/acs.joc.1c01394
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: Organocatalytic Asymmetric α-Allylation and Propargylation of α-Branched Aldehydes with Alkyl Halides

    Yoshida, Masanori

    Journal of organic chemistry. 2021 July 15, v. 86, no. 15

    2021  

    Abstract: Enantioselective α-allylation and -propargylation of α-branched aldehydes with alkyl halides was successfully performed using a chiral primary amino acid organocatalyst. This alkylation reaction, involving the generation of a chiral quaternary carbon ... ...

    Abstract Enantioselective α-allylation and -propargylation of α-branched aldehydes with alkyl halides was successfully performed using a chiral primary amino acid organocatalyst. This alkylation reaction, involving the generation of a chiral quaternary carbon stereocenter, proceeded smoothly in a mildly basic aqueous solution of potassium hydrogen carbonate to furnish α-allylated or -propargylated aldehydes in a good yield (up to 87%) and high enantioselectivity (up to 96% ee).
    Keywords alkylation ; amino acids ; aqueous solutions ; carbon ; catalytic activity ; enantioselectivity ; organic chemistry ; organocatalysts ; potassium bicarbonate
    Language English
    Dates of publication 2021-0715
    Size p. 10921-10927.
    Publishing place American Chemical Society
    Document type Article
    ZDB-ID 123490-0
    ISSN 1520-6904 ; 0022-3263
    ISSN (online) 1520-6904
    ISSN 0022-3263
    DOI 10.1021/acs.joc.1c01394
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  4. Article ; Online: Comments on "Assessment of changes in the liver of pregnant female rats and their fetuses following monosodium glutamate administration" by Gad El-Hak et al., http://doi.org/10.1007/s11356-021-13,557-7.

    Yoshida, Shintaro / Kohmura, Masanori

    Environmental science and pollution research international

    2022  Volume 30, Issue 6, Page(s) 16775–16777

    MeSH term(s) Pregnancy ; Rats ; Animals ; Female ; Sodium Glutamate ; Liver ; Fetus
    Chemical Substances Sodium Glutamate (W81N5U6R6U)
    Language English
    Publishing date 2022-10-28
    Publishing country Germany
    Document type Letter ; Comment
    ZDB-ID 1178791-0
    ISSN 1614-7499 ; 0944-1344
    ISSN (online) 1614-7499
    ISSN 0944-1344
    DOI 10.1007/s11356-022-23858-0
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  5. Article ; Online: Injectable Testosterone PLGA Microsphere with Different Characteristics: Effect of Preparation Method (Paddle Mixing versus Microfluidic Device).

    Oe, Yusuke / Kobayashi, Masanori / Yoshida, Takayuki / Kojima, Hiroyuki / Terukina, Takayuki / Kondo, Hiromu

    Pharmaceutical development and technology

    2024  , Page(s) 1–17

    Abstract: The purpose of this study was to compare the characteristics of testosterone polylactic-co-glycolic (PLGA) microspheres prepared by a paddle mixer or microfluidics device. The comparison was conducted by not ... ...

    Abstract The purpose of this study was to compare the characteristics of testosterone polylactic-co-glycolic (PLGA) microspheres prepared by a paddle mixer or microfluidics device. The comparison was conducted by not only
    Language English
    Publishing date 2024-04-29
    Publishing country England
    Document type Journal Article
    ZDB-ID 1331774-x
    ISSN 1097-9867 ; 1083-7450
    ISSN (online) 1097-9867
    ISSN 1083-7450
    DOI 10.1080/10837450.2024.2348580
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    Zs.A 5043: Show issues Location:
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  6. Article ; Online: Detection of CpG methylation level using methyl-CpG-binding domain-fused fluorescent protein.

    Fujita, Marika / Goto, Masanori / Tanaka, Masayoshi / Yoshida, Wataru

    Analytical methods : advancing methods and applications

    2023  Volume 15, Issue 19, Page(s) 2294–2299

    Abstract: Methylation of cytosine to 5-methylcytosine on CpG dinucleotides is the most frequently studied epigenetic modification involved in the regulation of gene expression. In normal tissues, tissue-specific CpG methylation patterns are established during ... ...

    Abstract Methylation of cytosine to 5-methylcytosine on CpG dinucleotides is the most frequently studied epigenetic modification involved in the regulation of gene expression. In normal tissues, tissue-specific CpG methylation patterns are established during development. In contrast, alterations in methylation patterns have been observed in abnormal cells, such as cancer cells. Cancer type-specific CpG methylation patterns have been identified and used as biomarkers for cancer diagnosis. In this study, we developed a hybridization-based CpG methylation level sensing system using a methyl-CpG-binding domain (MBD)-fused fluorescent protein. In this system, the target DNA is captured by a complementary methylated probe DNA. When the target DNA is methylated, a symmetrically methylated CpG is formed in the double-stranded DNA. MBD specifically recognizes symmetrical methyl-CpG on double-stranded DNA; therefore, the methylation level is quantified by measuring the fluorescence intensity of the bound MBD-fused fluorescent protein. We prepared MBD-fused AcGFP1 and quantified the CpG methylation levels of the target DNA against
    MeSH term(s) DNA-Binding Proteins/chemistry ; DNA-Binding Proteins/genetics ; DNA-Binding Proteins/metabolism ; CpG Islands/genetics ; DNA Methylation/genetics ; Cytosine/chemistry ; DNA/chemistry
    Chemical Substances DNA-Binding Proteins ; Cytosine (8J337D1HZY) ; DNA (9007-49-2)
    Language English
    Publishing date 2023-05-18
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2515210-5
    ISSN 1759-9679 ; 1759-9660
    ISSN (online) 1759-9679
    ISSN 1759-9660
    DOI 10.1039/d3ay00227f
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  7. Article ; Online: Asymmetric α-Allylation of α-Substituted β-Ketoesters with Allyl Alcohols.

    Yoshida, Masanori

    The Journal of organic chemistry

    2017  

    Abstract: Enantioselective α-allylation of α-substituted β-ketoesters with simple allyl alcohols was successfully performed by synergistic catalysis with the catalyst combination of a chiral primary amino acid and an achiral palladium complex without additional ... ...

    Abstract Enantioselective α-allylation of α-substituted β-ketoesters with simple allyl alcohols was successfully performed by synergistic catalysis with the catalyst combination of a chiral primary amino acid and an achiral palladium complex without additional promotors like acids or bases. The allylation reaction and generation of a chiral quaternary carbon stereocenter proceeded smoothly to produce α,α-disubstituted β-ketoesters in high yields (91-99%) with high enantioselectivities (90-99% ee).
    Language English
    Publishing date 2017-10-27
    Publishing country United States
    Document type Journal Article
    ZDB-ID 123490-0
    ISSN 1520-6904 ; 0022-3263
    ISSN (online) 1520-6904
    ISSN 0022-3263
    DOI 10.1021/acs.joc.7b02188
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    Zs.A 4473: Show issues Location:
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  8. Article ; Online: Comment on Nahok et al. Monosodium Glutamate Induces Changes in Hepatic and Renal Metabolic Profiles and Gut Microbiome of Wistar Rats.

    Chao, Huichia / Yoshida, Shintaro / Kohmura, Masanori

    Nutrients

    2022  Volume 14, Issue 20

    Abstract: This letter is to comment on the study of Nahok, K. et al. [ ... ]. ...

    Abstract This letter is to comment on the study of Nahok, K. et al. [...].
    MeSH term(s) Rats ; Animals ; Sodium Glutamate/pharmacology ; Rats, Wistar ; Gastrointestinal Microbiome ; Nutrients ; Metabolome
    Chemical Substances Sodium Glutamate (W81N5U6R6U)
    Language English
    Publishing date 2022-10-19
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2518386-2
    ISSN 2072-6643 ; 2072-6643
    ISSN (online) 2072-6643
    ISSN 2072-6643
    DOI 10.3390/nu14204386
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  9. Article ; Online: Stability and bonding nature of positronic lithium molecular dianion.

    Ito, Shumpei / Yoshida, Daisuke / Kita, Yukiumi / Shimazaki, Tomomi / Tachikawa, Masanori

    The Journal of chemical physics

    2023  Volume 158, Issue 20

    Abstract: We studied the stability of a system consisting of a positron (e+) and two lithium anions, [Li-; e+; Li-], using first-principles quantum Monte Carlo calculations combined with the multi-component molecular orbital method. While diatomic lithium ... ...

    Abstract We studied the stability of a system consisting of a positron (e+) and two lithium anions, [Li-; e+; Li-], using first-principles quantum Monte Carlo calculations combined with the multi-component molecular orbital method. While diatomic lithium molecular dianions Li22- are unstable, we found that its positronic complex can form a bound state with respect to the lowest energy decay into the dissociation channel Li2- and a positronium (Ps). The [Li-; e+; Li-] system has the minimum energy at the internuclear distance of ∼3 Å, which is close to the equilibrium internuclear distance of Li2-. At the minimum energy structure both an excess electron and a positron are delocalized as orbiting around the Li2- molecular anion core. A dominant feature of such a positron bonding structure is described as the Ps fraction bound to Li2-, unlike the covalent positron bonding scheme for the electronically isovalent [H-; e+; H-] complex.
    Language English
    Publishing date 2023-05-26
    Publishing country United States
    Document type Journal Article
    ZDB-ID 3113-6
    ISSN 1089-7690 ; 0021-9606
    ISSN (online) 1089-7690
    ISSN 0021-9606
    DOI 10.1063/5.0150246
    Database MEDical Literature Analysis and Retrieval System OnLINE

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    Z 4' 49/16: Show issues

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  10. Article ; Online: Tunable polarization volume gratings based on blue phase liquid crystals.

    Cho, SeongYong / Yoshida, Hiroyuki / Ozaki, Masanori

    Optics express

    2022  Volume 30, Issue 2, Page(s) 1607–1614

    Abstract: A large-angle polarization volume grating (PVG) with circular-polarization selectivity is demonstrated using a three-dimensional chiral liquid crystal with simple cubic symmetry - the blue phase (BP) II. We confirm defect-free alignment of the BP crystal ...

    Abstract A large-angle polarization volume grating (PVG) with circular-polarization selectivity is demonstrated using a three-dimensional chiral liquid crystal with simple cubic symmetry - the blue phase (BP) II. We confirm defect-free alignment of the BP crystal on a periodically patterned substrate down to a period of 700 nm, with Kossel diagrams and far-field diffraction patterns suggesting that the lattice becomes slanted within the cell to accommodate to the imprinted pattern. We further demonstrate a tunable PVG by exploiting the external field-responsivity of BPs, making this PVG attractive for a wide range of applications from tunable photonics to augmented reality.
    Language English
    Publishing date 2022-02-21
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1491859-6
    ISSN 1094-4087 ; 1094-4087
    ISSN (online) 1094-4087
    ISSN 1094-4087
    DOI 10.1364/OE.448301
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