Chemical and Pharmaceutical Bulletin
Online ISSN : 1347-5223
Print ISSN : 0009-2363
ISSN-L : 0009-2363
Featured articles
Showing 181-199 articles out of 199 articles
  • Volume 65 (2017) Issue 10 Pages 940-944
    Versatile Amine-Promoted Mild Methanolysis of 3,5-Dinitrobenzoates and Its Application to the Synthesis of Colorado Potato Beetle Pheromone Read more
    Editor’s picks

    In the article, a mild deacylation method for 3,5-dinitrobenzoates, which are often used to improve their diastereomeric or enantiomeric purities by recrystallization and also widely used as a pro-nucleophile in the Mitsunobu reaction, has been developed by using methanolic solutions of amines, such as dialkylamines. Removal of dinitrobenzoyl groups undergoes without affecting existing acetyl groups and also without affecting stereochemistry in α-hydroxy ketone. Encouraged by the promising versatility, the authors successfully applied this method to the efficient asymmetric synthesis of Colorado potato beetle pheromone.

  • Volume 65 (2017) Issue 10 Pages 930-939
    Microtropins Q–W, ent-Labdane Glucosides: Microtropiosides G–I, Ursane-Type Triterpene Diglucoside and Flavonol Glycoside from the Leaves of Microtropis japonica Read more
    Editor’s picks

    Since an antileukemic ansa macrolide, maytansine was first isolated from Maytenus ovata, plants belong to Celastraceae draw the attention of natural product chemists. The authors focused on the plants collected in Okinawa Islands, and Celastraceae plant, Microtropis japonica was chosen for the target material. ent-Labdane glycoside and 6'-O-(2"S,3R")-2"-ethyl-2",3"-dihydroxybutyrates of aliphatic alcohol β-D-glucosides branches have been isolated from leaves and branches respectively. Current investigation of leaves afforded further ent-labdane glucosides, 6'-O-2"-ethyl-2",3"-dihydroxybutyrates of aliphatic alcohol β-D-glucosides, ursane-type triterpene diglucoside, and flavonol glycoside.

  • Volume 65 (2017) Issue 9 Pages 862-868
    Ethereal C–O Bond Cleavage Mediated by Ni(0)-Ate Complex: A DFT Study Read more
    Editor’s picks

    Density functional theory calculations were performed to explore the mechanism of Ni-catalyzed cross-coupling reactions involving organo-lithium and -zinc reagents though ethereal C–O bond cleavage. In comparison with our previous mechanistic study on etheric Kumada–Tamao reaction, it shows that the the Ni(0)-ate complex-mediated reaction pathway is a new and general mechanism for ethereal cross-coupling reactions, which can well explain the experimental findings for several ethereal C–O bond cleavage couplings.  The present work also suggests that the anionic character of organometallic nucleophiles can change oxidative addition mechanisms/pathways, which may provide new reactivity and selectivity.

  • Volume 65 (2017) Issue 9 Pages 848-853
    Effect of the External Lubrication Method for a Rotary Tablet Press on the Adhesion of the Film Coating Layer Read more
    Editor’s picks

    We evaluated the adhesion force of the film coating layer to the surface of tablets prepared using an external lubrication method. Increasing lubrication decreased wettability of the tablet surface. However, no change was observed in the adhesion force of the film coating layer. The magnesium stearate distribution state on the tablet surface was assessed and the lubricant was uniformly dispersed in the external lubrication samples. The distribution state of the lubricant affects the adhesion force of the film coating layer, and external lubrication maintained sufficient lubricity and adhesion force of the film coating layer with a small amount of lubricant.

  • Volume 65 (2017) Issue 9 Pages 840-847
    Four New Lignans and IL-2 Inhibitors from Magnoliae Flos Read more
    Editor’s picks

    Four new lignans, a furofuran lignan medioresinol B (10) and three tetrahydrofuran lignans kobusinol C (16), 7'-methoxy magnostellin A (21), and mangnostellin D (23), along with 19 known lignans, were isolated from the flower buds of Magnolia biondii Pamp. The structures of the isolates were elucidated using spectroscopic analysis, mainly one- and two-dimensional NMR, high resolution mass spectrometry, and circular dichroism techniques as well as Mosher’s esterification method. The anti-allergic effects of the isolated compounds were evaluated by analyzing the inhibition of interleukin-2 (IL-2) expression in Jurkat T-cells. Compounds 1114 reduced IL-2 expression in a dose-dependent manner.

  • Volume 65 (2017) Issue 8 Pages 796-800
    7-Hydroxy-3-methyleneisoindolin-1-one as a New ESIPT-Fluorescent Probe to Monitor Aqueous Environments Read more
    Editor’s picks

    Fluorophores undergoing excited-state intramolecular proton transfer (ESIPT) exhibit several unique characteristics. In the paper, a range of 7-hydroxy-3-methyleneisoindolin-1-ones is investigated as new ESIPT fluorophores. In fact, dual emission is observed in alcohols and DMSO; ~380 and ~530 nm (exc. = ~336 nm), and a single emission is observed (~500 nm) in EtOH-H2O binary mixtures. Furthermore, the wavelength of fluorescence maxima is dependent on the dielectric constant of the solvent, suggesting their potential utility for monitoring aqueous environments.

  • Volume 65 (2017) Issue 8 Pages 784-795
    Efficient Synthesis of Heterocyclic Flavonoids with Hedgehog Signal Inhibitory Activity Read more
    Editor’s picks

    The hedgehog (Hh) signaling pathway performs important roles in cellular process, however, in many cancer cells Hh signaling is aberrantly activated, which has provided a strong impetus for the development of Hh pathway inhibitors. In the paper, a series of heterocyclic flavonoids are prepared and evaluate their Hh signaling inhibitory activity. As a result, some of the synthetic flavonoids show good Hh inhibitory activity as well as cytotoxicity toward human cancer cells. Western blotting analyses also reveal that PTCH and GLI1 expression is reduced. 

  • Volume 65 (2017) Issue 8 Pages 726-731
    Melt Adsorption as a Manufacturing Method for Fine Particles of Wax Matrices without Any Agglomerates Read more
    Editor’s picks

    This paper focuses on melt adsorption as manufacture method of wax matrices to control particles size of granules more easily than melt granulation, and demonstrated for the first time that melt adsorption using a hydrophobic material has the potential capability to control the particle size of granules and offers the possibility of application as a novel controlled release technique.

  • Volume 65 (2017) Issue 7 Pages 605-610
    Potential of Enzymomics Methodologies to Characterize Disease-Related Protein Functions Read more
    Editor’s picks

    Cellular functions are mediated by a great variety of enzymes, and altered enzymatic functions are often observed during disease onset and progression. Therefore, discovering the novel connection between the functions of enzymes and specified diseases is the key to developing novel diagnostic methods, as well as therapeutic drugs.  In this review, we describe the recently advancing field of chemical biology that aims to discover and characterize disease-related alternation of enzymatic functions, which can be termed as “enzym-omics (omics of enzymes)”.  The review covers several key technologies that can be considered as the representative experimental systems used for this purpose.  

  • Volume 65 (2017) Issue 6 Pages 511-523
    Creation of Novel Cyclization Methods Using sp-Hybridized Carbon Units and Syntheses of Bioactive Compounds Read more
    Editor’s picks

    In this review, new and reliable procedures for the construction of diverse ring systems based on the chemistry of sp-hybridized species are described. The synthetic application includes (i) multi-cyclic skeletons by the Rh-catalyzed reaction of allenes with other π-components such as alkyne, alkene, and allene, (ii) hetero- and carbocycles from appropriate allenes and nucleophiles, and (iii) natural products and related compounds.

  • Volume 65 (2017) Issue 5 Pages 409-425
    Palladium(0)-Catalyzed Benzylic C(sp3)–H Functionalization for the Concise Synthesis of Heterocycles and Its Applications Read more
    Editor’s picks

    This review summarizes author’s recent reports on Pd(0)-catalyzed benzylic C(sp3)-H functionalization for the synthesis of various heterocycles including oxindoles, spirooxindoles, 2-arylindoles, benzocarbazoles, indolocarbazoles, and indoloquinazolinones. The key feature would be a chemoselective C(sp3)-H activation in the oxindole synthesis. The developed method was successfully applied to the total synthesis of several pyrrolophenanthridine alkaloids as well as a synthesis of the right-hand fragment of benzohopane.

  • Volume 65 (2017) Issue 4 Pages 356-358
    Alternative Formation of Red-Shifted Channelrhodopsins: Noncovalent Incorporation with Retinal-Based Enamine-Type Schiff Bases and Mutated Channelopsin Read more
    Editor’s picks

    In this communication, development of a new type of red-shifted channelrhodopsins (ChRs) is described. Optogenetics is a powerful new technique which allows control of neuronal activity by light, and ChRs are now widely used in optogenetics due to their function of a light-gated cation channel. In neuroscience, ChRs responding to a long-wavelength light are eagerly required, because ChRs now used are maximally sensitive to green and blue light, and does not penetrate tissues. Here developed new type of ChRs model consisted of red-shifted chromophores (retinal-based enamine-type Schiff bases) and mutated channelopsin (C1C2-K296G), in which chromophores were incorporated noncovalently. Thus prepared new ChRs exhibited absorption maxima that were 10-30 nm red-shifted compared with the original C1C2.

  • Volume 65 (2017) Issue 3 Pages 268-275
    Adsorption Capability of Cationic Dyes (Methylene Blue and Crystal Violet) onto Poly-γ-glutamic Acid Read more
    Editor’s picks

    In this paper, the adsorption capacity of methylene blue (MB) and crystal violet (CV) to poly-γ-glutamic acid (PGA) is described. PGA contained in natto (Japanese traditional fermented food) is a homopolyamide having bonds between α-amino and γ-carboxy groups of D- and L-glutamic acid monomers. The removal rate of MB or CV by PGA was 94.6 to 100% after 120 min. In addition, PGA has a dye adsorption capacity in a binary solution system. The results of this study indicate that PGA is useful for removing dyes from aqueous solutions.

  • Volume 65 (2017) Issue 2 Pages 157-165
    Design of Highly Dispersible PLGA Microparticles in Aqueous Fluid for the Development of Long-Acting Release Injectables Read more
    Editor’s picks

    In this article, injectable products composed of biocompatible and biodegradable poly-lactic glycolic acid copolymer (PLGA) microparticles are described. In order to improve the dispersibility of MRPs in injection solutions, MRPs were subjected to a secondary processing, i.e., the drop freeze-drying technique. The suspension with MRPs and water-soluble additives were rapidly dripped into liquid nitrogen in the form of droplets. The resultant frozen particles were freeze-dried to prepare spherical granules containing multiple MRPs (Granulated-MRPs). When the G-MRPs were placed in water for injection, the porous matrix base was immediately dissolved, and each embedded MRPs were individually released, thus inducing monodispersion and significantly improved dispersibility. The granular products could be automatically filled into the pre-filled syringes and may give rise to the excellent passage of PLGA MRPs through needles for use in depot injected formulation as a ready-to-use.

  • Volume 65 (2017) Issue 1 Pages 33-35
    Photo-Induced Atom-Transfer Radical Reactions Using Charge–Transfer Complex between Iodine and Tertiary Amine Read more
    Editor’s picks

    In this paper, the authors used the charge-transfer complexes between iodine and tertiary amines for the initiation of atom-transfer radical reactions. The visible light irradiation of charge-transfer complex in the ground state gives the excited state complex, in which the single electron transfer from the donor amine to the acceptor iodine proceeds effectively to give an iodine radical.

  • Volume 64 (2016) Issue 12 Pages 1692-1697
    Effect of Nerolidol and/or Levulinic Acid on the Thermotropic Behavior of Lipid Lamellar Structures in the Stratum Corneum Read more
    Editor’s picks

    In this study, the authors focused on two permeation enhancers: nerolidol and levulinic acid to clarify the mechanism of action of permeation enhancers on lipids structures. Synchrotron X-ray diffraction revealed that nerolidol strongly affected the orthorhombic and hexagonal structures, whereas levulinic acid had little effect on the lateral packing structures.

  • Volume 64 (2016) Issue 11 Pages 1533-1538
    Identification of Lung Inflammation-Related Elevation of Acylamino Acid Releasing Enzyme (APEH) Activity Using an Enzymomics Approach Read more
    Editor’s picks

    In this paper, the authors used a panel of fluorogenic substrates to search for altered enzyme activities in bronchoalveolar lavage fluid (BALF) from a mouse model of lung inflammation and found that acylamino acid releasing enzyme (APEH) activity was highly elevated, apparently reflecting the increased population of immune cells in the inflamed lung.

  • Volume 64 (2016) Issue 10 Pages 1431-1437
    Current Understanding of Direct Translocation of Arginine-Rich Cell-Penetrating Peptides and Its Internalization Mechanisms Read more
    Editor’s picks

    In the review, the authors summarize recent reports on direct translocation of arginine-rich cell-penetrating peptides (CPPs) through cell membranes, including counteranion-assisted delivery method, and discuss its mechanism, which would provide insight into highly efficient intracellular delivery.

  • Volume 64 (2016) Issue 9 Pages 1249-1255
    Photocontrol of NO, H2S, and HNO Release in Biological Systems by Using Specific Caged Compounds Read more
    Editor’s picks

    This review summarizes the authors’ recent work on photocontrolable releases, or caged compounds, which can release specific biological mediators such as NO, HNO, and H2S, upon photoirradiation, and a wide range of colors (wavelengths), from ultraviolet to near infrared, are available depending on the properties of the compounds. These photocontrollable compounds realized the spatiotemporal control of the release, and the manipulation of biological responses specific for the mediators. One of our photocontrollable NO releasers with the near infrared two photon excitation succeeded to control vasodilation in the anesthetized mouse brain with spatiotemporal resolution, and the ex vivo rat aorta relaxation was also achieved with another controllable NO releaser by the visible light irradiation.