Chemical and Pharmaceutical Bulletin
Online ISSN : 1347-5223
Print ISSN : 0009-2363
ISSN-L : 0009-2363
Volume 60 , Issue 9
Showing 1-21 articles out of 21 articles from the selected issue
Communication to the Editor
Regular Articles
  • Hiroki Murakami, Hiroyuki Yasui, Yutaka Yoshikawa
    Type: Regular Article
    2012 Volume 60 Issue 9 Pages 1096-1104
    Published: September 01, 2012
    Released: September 01, 2012
    JOURNALS FREE ACCESS
    Zn(II) complexes are expected to be useful in the treatment of diabetes mellitus because of the hypoglycemic effect produced by its insulin-mimetic activity. Previous reports indicated that Zn(II) complexes with coordinating sulfur exhibit higher insulin-mimetic activity. In this study, we investigated the pharmacological and pharmacokinetic differences between Zn(O4) and Zn(S2O2) coordination modes of tropolonato–Zn(II) complexes with insulin-mimetic activity. Among the tropolonato–Zn(II) complexes with various coordination modes, di(2-mercaptotropolonato)zinc(II) (ZT2) with the Zn(S2O2) coordination mode was found to exhibit the highest in vitro insulin-mimetic activity with respect to inhibition of free fatty acid (FFA) release and enhancement of glucose uptake in isolated rat adipocytes treated with adrenaline. On comparing investigations of the antidiabetic effect in vivo, ZT2 was found to exhibit potent hypoglycemic activity and improve insulin resistance in type 2 diabetic KKAy mice at a low orally administered daily dose. Di(tropolonato)zinc(II) (ZT1), which has the Zn(O4) coordination mode, had a lesser effect at the same dose. In a pharmacokinetic analysis based on the 65Zn tracer method, ZT2 was found to be absorbed at a significantly slower rate with a longer half-life than was ZT1. These results suggest that the potent hypoglycemic activity of ZT2 might be attributed to its long half-life.
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  • Hiroko Shibata, Haruna Saito, Chikako Yomota, Toru Kawanishi, Haruhiro ...
    Type: Regular Article
    2012 Volume 60 Issue 9 Pages 1105-1111
    Published: September 01, 2012
    Released: September 01, 2012
    JOURNALS FREE ACCESS
    We have investigated the effects of two bile salts, chenodeoxycholate (CDC) and ursodeoxycholate (UDC), and a widely used detergent, Triton X-100 (TX-100), on normal and poly(ethylene glycol)-modified liposomes (PEGylated liposomes). We tested various lipid compositions, including hydrogenated soybean phosphatidylcholine/cholesterol/PEG-conjugated lipid (HSPC/PEG-lipid). Alterations in permeability were determined by the rate of drug release from the liposomes and solubilization was assessed by measuring the particle size of liposomes. In addition, we attempted to observe interactions between the detergents and lipid bilayers by using surface plasmon resonance (SPR). CDC induced drug release from liposomes in a dose-dependent manner, and the PEGylated liposomes tended to be susceptible to CDC. While UDC did not strongly induce drug release from liposomes, UDC exhibited a similar tendency with CDC. In case of TX-100, there were significant differences in the percentage of released drug between normal and PEGylated liposomes, and the percentage of TX-100-induced drug release further increased with an increased ratio of PEG-lipid. SPR analysis revealed that the lipid bilayer including PEG-lipid was selectively solubilized by TX-100, correlating with the drug release data. These results suggest that the effect of detergents on the lipid bilayer of liposomes depends on both the kind of detergent and the lipid composition, including the presence or absence of PEG-lipid. Moreover, the effects of TX-100 on the lipid bilayers of the PEGylated liposomes significantly differed from those on the lipid bilayers of the normal liposomes.
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  • Matsutake Higa, Megumi Imamura, Kanae Shimoji, Kazuhito Ogihara, Toshi ...
    Type: Regular Article
    2012 Volume 60 Issue 9 Pages 1112-1117
    Published: September 01, 2012
    Released: September 01, 2012
    JOURNALS FREE ACCESS
    Six new flavonoids—5-hydroxy-3,8-dimethoxy-3′,4′:6,7-bismethylenedioxyflavone (1), 3,3′,4′,5-tetramethoxy-7-(3-methylbut-2-enyloxy)flavone (2), 7-(2-hydroxy-3-methylbut-3-enyloxy)-3,3′,4′,5-tetramethoxyflavone (3), 7-(2-hydroxy-3-methylbut-3-enyloxy)-3,5-dimethoxy-3′,4′-methylenedioxyflavone (4), 7-(2-hydroxy-3-methylbut-3-enyloxy)-3,3′,4′,5,8-pentamethoxyflavone (5), and 7-(2-hydroxy-3-methylbut-3-enyloxy)-3,5,8-trimethoxy-3′,4′-methylenedioxyflavone (6)—were isolated from the leaves of Melicope triphylla. In addition, six already known flavonoids were also detected: 5-hydroxy-3,6,7-trimethoxy-3′,4′-methylenedioxyflavone (7), 5,7-dihydroxy-3,3′,4′,8-tetramethoxyflavone (8), 4′,5-dihydroxy-3,3′,7,8-tetramethoxyflavone (9), 3,5,6,7,8-pentamethoxy-3′,4′-methylenedioxyflavone (10), 3,5,6,7-tetramethoxy-3′,4′-methylenedioxyflavone (11), and 3,3′,4′,5,6,7,8-heptamethoxyflavone (12). The structures of the new compounds were established by spectroscopic methods. Compound 2 displayed ichthyotoxic activity against Japanese killifish (medaka in Japanese) (Oryzias latipes var.) at 10 ppm.
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  • Chi-Hsien Liu, Hsin-Ying Huang
    Type: Regular Article
    2012 Volume 60 Issue 9 Pages 1118-1124
    Published: September 01, 2012
    Released: September 01, 2012
    JOURNALS FREE ACCESS
    The bactericidal properties of myristic acid and curcumin were revealed in a number of studies. However, whether curcumin-loaded myristic acid microemulsions can be used to inhibit Staphylococcus epidermidis, which causes nosocomial infections, has not been reported. Our aim was to develop curcumin-loaded myristic acid microemulsions to inhibit S. epidermidis on the skin. The interfacial tension, size distribution, and viscosity data of the microemulsions were characterized to elucidate the physicochemical properties of the curcumin microemulsions. Curcumin distribution in neonate pig skin was visualized using confocal laser scanning microscopy. Dermal curcumin accumulation (326 µg/g skin) and transdermal curcumin penetration (87 µg/cm2/d) were obtained with the microemulsions developed herein. Curcumin at the concentration of 0.86 µg/mL in the myristic acid microemulsion could inhibit 50% of the bacterial growth, which was 12 times more effective than curcumin dissolved in dimethyl sulfoxide (DMSO). The cocktail combination of myristic acid and curcumin in the microemulsion carrier synergistically inhibited the growth of S. epidermidis. The results we obtained highlight the potential of using curcumin-loaded microemulsions as an alternative treatment for S. epidermidis-associated diseases and acne vulgaris.
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  • Thi Nga Vo, Phi Linh Nguyen, Lam Truong Tuong, Lawrence Michael Pratt, ...
    Type: Regular Article
    2012 Volume 60 Issue 9 Pages 1125-1133
    Published: September 01, 2012
    Released: September 01, 2012
    JOURNALS FREE ACCESS
    Supplementary material
    Two new lignans, pseuderesinol (1), pseuderanoside (2) and a new triterpene, pseuderanic acid (3) were isolated from the dried root of Pseuderanthemum carruthersii (SEEM.) GUILL. var. atropurpureum (BULL.) FOSB. (Acanthaceae), together with ten known compounds, including five lignans, (+)-eudesmin (4), (+)-magnolin (5), (+)-syringaresinol (6), (+)-episyringaresinol (7), (+)-1-hydroxysyringaresinol (8) and five triterpenes, squalene (9), oleanolic acid (10), lupeol (11), betulin (12), betulinic acid (13). Their chemical structures were elucidated by 1D- and 2D-NMR, computational quantum chemistry, as well as high resolution-electrospray ionization (HR-ESI)-MS spectroscopic analysis. The acetylcholinesterase inhibition and cytotoxic activities against HeLa and MCF-7 cancer cell lines were evaluated on some purified compounds at the concentration of 100 µg/mL. Pseuderesinol (1) and magnolin (5) exhibited moderate cytotoxic activities against the MCF-7 cancer cell line.
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  • Makoto Tamaki, Takuji Harada, Kenta Fujinuma, Kazumasa Takanashi, Mits ...
    Type: Regular Article
    2012 Volume 60 Issue 9 Pages 1134-1138
    Published: September 01, 2012
    Released: September 01, 2012
    JOURNALS FREE ACCESS
    The substitution of each constituent amino acid residue of gramicidin S (GS), cyclo(-Val1,1′-Orn2,2′-Leu3,3′-D-Phe4,4′-Pro5,5′-)2 with Lys residue indicated that each side chain structure of the constituent amino acid residues affect largely the antibiotic activity and hemolytic activity of GS. Further, the substitution of D-Phe4,4′ and Pro5,5′ residues with basic amino acid residues as a Lys residue results the high antibiotic activity and the very low hemolytic activity. Thus, we have found novel positions on the scaffold of GS at D-Phe4,4′ and Pro5,5′ residues whose modification will significantly increase the therapeutic index.
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  • Julie Rakel Mikell, Ikhlas Ahmad Khan
    Type: Regular Article
    2012 Volume 60 Issue 9 Pages 1139-1145
    Published: September 01, 2012
    Released: September 01, 2012
    JOURNALS FREE ACCESS
    Supplementary material
    Microbial metabolism of 7-hydroxyflavanone (1) with fungal culture Cunninghamella blakesleeana (ATCC 8688a), yielded flavanone 7-sulfate (2), 7,4′-dihydroxyflavanone (3), 6,7-dihydroxyflavanone (4), 6-hydroxyflavanone 7-sulfate (5), and 7-hydroxyflavanone 6-sulfate (6). Mortierella zonata (ATCC 13309) also transformed 1 to metabolites 2 and 3 as well as 4′-hydroxyflavanone 7-sulfate (7), flavan-4-cis-ol 7-sulfate (8), 2′,4′-dihydroxychalcone (9), 7,8-dihydroxyflavanone (10), 8-hydroxyflavanone 7-sulfate (11), and 8-methoxy-7-hydroxyflavanone (12). Beauveria bassiana (ATCC 7159) metabolized 1 to 2, 3, and 8, flavanone 7-O-β-D-O-4-methoxyglucopyranoside (13), and 8-hydroxyflavanone 7-O-β-D-O-4-methoxyglucopyranoside (14). Chaetomium cochlioides (ATCC 10195) also transformed 1 to 2, 3, 9, together with 7-hydroxy-4-cis-ol (15). Mucor ramannianus (ATCC 9628) metabolized 1 in addition to 7, to also 4,2′,4′-trihydroxychalcone (16), 7,3′,4′-trihydroxyflavanone (17), 4′-hydroxyflavanone 7-O-α-L-rhamnopyranoside (18), and 7,3′,4′-trihydroxy-6-methoxyflavanone (19). The organism Aspergillus alliaceus (ATCC 10060) transformed 1 to metabolites 3, 16, 7,8,4′-trihydroxyflavanone (20), and 7-hydroxyflavanone 4′-sulfate (21). A metabolite of 1, flavanone 7-O-β-D-O-glucopyranoside (22) was produced by Rhizopus oryzae (ATCC 11145). Structures of the metabolic products were elucidated by means of spectroscopic data. None of the metabolites tested showed antibacterial, antifungal and antimalarial activities against selected organisms. Metabolites 4 and 16 showed weak antileishmanial activity.
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  • Yunfei Li, Feifei Yang, Wei Chen, Jiaoyang Liu, Wei Huang, Mingji Jin, ...
    Type: Regular Article
    2012 Volume 60 Issue 9 Pages 1146-1154
    Published: September 01, 2012
    Released: September 01, 2012
    JOURNALS FREE ACCESS
    Docetaxel (DTX) is hydrophobic, and its available formulations (Taxotere® & Duopafei®) require Tween80 and ethanol vehicle to allow parental administration. DTX-loaded poly(D,L-lactide)-b-polyethylene glycol–methoxy (mPEG-b-PDLLA) polymeric micelle (PM) is a Tween80-free formulation of DTX, which has been extensively studied but rarely involved with industrialization issues. In this work, novel DTX-PM with improved loading capacity and well-reconsitution ability was developed. The freeze-dried DTX-PM was analyzed by HPLC, transmission electron microscopy (TEM) and dynamic light scattering (DLS) to determine the DTX loading, micelle morphology and size respectively. The in vitro cytotoxic activity of DTX-PM in 4T1 cells was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and the corresponding in vivo study was assessed in BALB/c mice bearing 4T1 tumor through intravenous administration. The DTX-loading and efficiency into the micelles were 20.74±1.23% and 93.7±1.03% respectively, which was much higher than ever reported PM. The DTX-PM was spherical with a mean particle size of 16.62±0.31 nm, which suggested that they were able to selectively accumulate in solid tumors by enhanced permeability and retention (EPR) effect. Another important characteristic of DTX-PM is the long term storage and reuses as aqueous injection solution. Many kinds of lyoprotectants were also investigated and dextrose was found to an excellent one. Compared with Duopafei®, DTX-PM showed better cytotoxicity and anti-metastasis ability against 4T1 cells in vitro and in vivo. In conclusion, DTX-PM significantly enhanced drug-loading capacity of DTX and had well-reconsitution ability, which could be a promising drug delivery system for clinic.
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  • Jin Maeda, Tatsuya Suzuki, Kozo Takayama
    Type: Regular Article
    2012 Volume 60 Issue 9 Pages 1155-1163
    Published: September 01, 2012
    Released: September 01, 2012
    JOURNALS FREE ACCESS
    A reliable large-scale design space was constructed by integrating the reliability of a scale-up rule into the Bayesian estimation without enforcing a large-scale design of experiments (DoE). A small-scale DoE was conducted using various Froude numbers (X1) and blending times (X2) in the lubricant blending process for theophylline tablets. The response surfaces, design space, and their reliability of the compression rate of the powder mixture (Y1), tablet hardness (Y2), and dissolution rate (Y3) on a small scale were calculated using multivariate spline interpolation, a bootstrap resampling technique, and self-organizing map clustering. A constant Froude number was applied as a scale-up rule. Experiments were conducted at four different small scales with the same Froude number and blending time in order to determine the discrepancies in the response variables between the scales so as to indicate the reliability of the scale-up rule. Three experiments under an optimal condition and two experiments under other conditions were performed on a large scale. The response surfaces on the small scale were corrected to those on the large scale by Bayesian estimation using the large-scale results and the reliability of the scale-up rule. Large-scale experiments performed under three additional sets of conditions showed that the corrected design space was more reliable than the small-scale design space even when there was some discrepancy in the pharmaceutical quality between the manufacturing scales. This approach is useful for setting up a design space in pharmaceutical development when a DoE cannot be performed at a commercial large manufacturing scale.
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  • Hideharu Suzuki, Akihito Ishigami, Ayako Orimoto, Akihiro Matsuyama, S ...
    Type: Regular Article
    2012 Volume 60 Issue 9 Pages 1164-1170
    Published: September 01, 2012
    Released: September 01, 2012
    JOURNALS FREE ACCESS
    Supplementary material
    Several new amyloid-β (Aβ) aggregation inhibitors were synthesized according to our theory that a hydrophilic moiety could be attached to the Aβ-recognition unit for the purpose of preventing amyloid plaque formation. A distyrylbenzene-derivative, DSB(EEX)3, which consider the Aβ recognition unit (DSB, 1,4-distyrylbenzene) and expected to bind to amyloid fibrils (β-sheet structure), was combined with the hydrophilic aggregation disrupting element (EEX) (E, Glu; X, 2-(2-(2-aminoethoxy)ethoxy)acetic acid). This DSB(EEX)3 compound, compared to several others synthesized similarly, was found to be the most active for reducing Aβ toxicity toward IMR-32 human neuroblastoma cells. Moreover, its inhibition of Aβ-aggregation or fibril formation was directly confirmed by transmission electron microscopy and atomic force microscopy. These results suggest that the Aβ aggregation inhibitor DSB(EEX)3 disrupts clumps of Aβ protein and is a likely candidate for drug development to treat Alzheimer’s disease.
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  • Yun Chao, Chi-Te Huang, Li-Tse Fu, Yaw-Bin Huang, Yi-Hung Tsai, Pao-Ch ...
    Type: Regular Article
    2012 Volume 60 Issue 9 Pages 1171-1175
    Published: September 01, 2012
    Released: September 01, 2012
    JOURNALS FREE ACCESS
    In this study, submicron emulsions have been employed as a carrier for the topical application of kaempferol. The effect of components of submicron emulsions on the physicochemical properties and permeation capability of drug were evaluated. In case of drug-loaded submicron emulsions, the cumulative amount over 12 h (Q12 h), lag time and deposition in skin amount ranged from 13.0±3.4 to 236.1±21.2 µg/cm2, 1.7 to 5.3 h, and 1.10 to 7.76 µg/cm2, respectively, which indicated that the permeation parameters of kaempferol were markedly influenced by the component ratio. Kaempferol dispensed in isopropyl myristate was used as the control. The Q12 h, lag time and deposition amount in skin were 4.2±1.8 µg/cm2, 6.0 h and 2.25±0.60 µg/cm2, respectively. The data showed that used appropriate submicron emulsions as vehicle could significantly increase the Q12 h and deposition amount in skin and shorten the lag time, demonstrating that submicron emulsions have a potent enhancement effect for kaempferol transdermal delivery.
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  • Takuya Yamaki, Ryohei Ohdate, Eriko Nakadai, Yasuo Yoshihashi, Etsuo Y ...
    Type: Regular Article
    2012 Volume 60 Issue 9 Pages 1176-1181
    Published: September 01, 2012
    Released: September 01, 2012
    JOURNALS FREE ACCESS
    Component crystallization and physical collapse during freeze-drying of aqueous solutions containing protein-stabilizing L-arginine and citric acid mixtures were studied. Freeze-drying microscopy (FDM) and thermal analysis of the solute-mixture frozen solutions showed collapse onset at temperatures (Tc) approximately 10°C higher than their Tg′s (glass transition temperatures of the maximally freeze-concentrated solute phase). Experimental freeze-drying of these solutions at a low chamber pressure showed the occurrence of physical collapse at shelf temperatures close to or slightly higher than the Tc. Slower ice sublimation at higher chamber pressures induced the physical collapse from lower shelf temperatures. The large effect of chamber pressures on the collapse-inducing shelf temperatures confirmed significance of the sublimation-related heat loss on the sublimation interface temperature during the primary drying. Drying of the single-solute L-arginine solution resulted in cake-structure solids composed of its anhydrous crystal. Thermal and powder X-ray diffraction (PXRD) analysis suggested slow crystal nucleation of L-arginine dihydrate in the frozen solutions. Characterization of the frozen solutions and freeze-dried solids should enable rational formulation design and process control of amino acid-containing lyophilized pharmaceuticals.
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  • Takashi Sato, Yoshifumi Kinoshita, Hiroyuki Tsutsumi, Hideji Yamamoto, ...
    Type: Regular Article
    2012 Volume 60 Issue 9 Pages 1182-1187
    Published: September 01, 2012
    Released: September 01, 2012
    JOURNALS FREE ACCESS
    The content of a crude precipitate formed by creaming, which was made from a catechin mixture and caffeine, was investigated by an integral volume of H-2 proton signals of tea catechins in the 1H-NMR spectrum. Gallated catechins formed a crude precipitate more predominantly than non-gallated catechins. The 2,3-cis-non-gallated catechin (−)-epicatechin (EC) formed a 1 : 1 complex with caffeine, and 2,3-cis-gallated catechin (−)-epicatechin gallate (ECg) formed a 2 : 4 complex with caffeine. The π–π complexation site of EC with caffeine was only the A ring, whereas that of ECg included all aromatic rings, A, B, and B′. It was thought that the hydrophobicity of the 2 : 4 complex of ECg and caffeine was stronger than that of the 1 : 1 complex of EC and caffeine, with the result that the 2 : 4 complex of ECg and caffeine precipitated by creaming more predominantly than the 1 : 1 complex of EC and caffeine in aqueous solution.
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  • Katsuyoshi Fujimoto, Seikou Nakamura, Souichi Nakashima, Takahiro Mats ...
    Type: Regular Article
    2012 Volume 60 Issue 9 Pages 1188-1194
    Published: September 01, 2012
    Released: September 01, 2012
    JOURNALS FREE ACCESS
    The methanolic extract and its 1-butanol-soluble fraction from the flower buds of Camellia japonica, cultivated in Yunnan Province, China, showed inhibitory effects on melanogenesis in theophylline-stimulated B16 melanoma 4A5 cells. From the 1-butanol-soluble fraction, a new 28-nor-oleanane-type and three new oleanane-type triterpene saponins, sanchakasaponins A–D, were isolated together with four known triterpene saponins. Their chemical structures were elucidated on the basis of chemical and physicochemical evidence. The inhibitory effects on melanogenesis in theophylline-stimulated B16 melanoma 4A5 cells and structure–activity relationships of the saponins were investigated.
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  • Mona Maurice Hanna, Riham François George
    Type: Regular Article
    2012 Volume 60 Issue 9 Pages 1195-1206
    Published: September 01, 2012
    Released: September 01, 2012
    JOURNALS FREE ACCESS
    Supplementary material
    2-(5-Arylidene-4-oxo-3-phenyl-thiazolidin-2-ylidene)-3-oxo-propionitriles 4aj were prepared via condensation of aromatic aldehydes with 4-thiazolidinones 3a, b. The latter was obtained via electrophilic attack of phenylisothiocyanate on 3-oxo-propionitriles 1a, b followed by reaction with chloroacetyl chloride under basic condition. Additionally, 2-(5-heteroalicyclic methylene) analogues 5ah were prepared via Mannich reaction of the appropriate secondary amines and formaldehyde with 4-thiazolidinones 3a, b. Many of the synthesized compounds exhibited promising antitumor properties against colon HCT116 and breast T47D cell lines. 3D-Pharmacophore modeling and quantitative structure–activity relationship (QSAR) analysis were combined to explain the observed antitumor properties.
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Notes
  • Hirohito Ikeda, Erika Tsuji, Tomonori Matsubara, Miho Yukawa, Masao Fu ...
    Type: Note
    2012 Volume 60 Issue 9 Pages 1207-1211
    Published: September 01, 2012
    Released: September 01, 2012
    JOURNALS FREE ACCESS
    Here, we studied the incompatibility between an oral solution of propericiazine (PCZ), an antipsychotic drug, and various commercially available bottled tea-based drinks. When 0.5 mL of the PCZ oral solution (10 mg/mL) was mixed with 16.5 mL of a tea-based drink (such as green tea, oolong tea, and black tea), the residual PCZ content declined to approximately 50% in some mixed solutions. After mixing with other tea-based drinks, the residual PCZ content declined to approximately 30%, while in others, it changed very little. The residual PCZ content declined immediately after mixing with tea-based drinks, but the rate remained almost unchanged for the next 24 h. Furthermore, the pH of the mixture increased to 4.5–5.1 after the oral solution of PCZ (original pH 3.8) was diluted with various tea-based drinks. Afterwards, the pH did not change for 24 h. The mixture became cloudy immediately after diluting PCZ oral solution with tea-based drinks, and the insoluble substance gradually precipitated. In order to elucidate factors responsible for the decline in the content of PCZ, a (−)-epigallocatechin gallate solution, which is a main ingredient of green tea polyphenol, was mixed with the PCZ oral solution. After mixing, the residual PCZ content declined to approximately 60–75%. On the other hand, the content of PCZ did not decline when a (−)-epigallocatechin solution was mixed with the PCZ oral solution. The results from this study demonstrated that PCZ content was reduced after dilution in tea-based drinks because of the interaction between PCZ and polyphenol with a galloyl group in tea-based drinks.
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  • Seigo Nagata, Kazuchika Takagaki, Takeshi Wada
    Type: Note
    2012 Volume 60 Issue 9 Pages 1212-1215
    Published: September 01, 2012
    Released: September 01, 2012
    JOURNALS FREE ACCESS
    We have developed an improved solid-phase method for the synthesis of 5′-triphosphates (5′-TPs) of oligoribonucleotides. The method is based on the use of salicyl phosphorochloridite as the phosphitylating reagent and the improvement is characterized by the use of the highly reactive pyrophosphorylating reagent tris(tetra-n-butylammonium) hydrogen pyrophosphate instead of the conventional tri-n-butylammonium salt for the nucleophilic substitution reaction to form the cyclic ester intermediate. The improved method can be used to generate oligoribonucleotide 5′-TPs efficiently and reproducibly.
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  • Yuko Masuda, Ryuichiro Suzuki, Hiroshi Sakagami, Naoki Umemura, Yoshia ...
    Type: Note
    2012 Volume 60 Issue 9 Pages 1216-1219
    Published: September 01, 2012
    Released: September 01, 2012
    JOURNALS FREE ACCESS
    A new phenanthrenequinone, 5-hydroxy-2,3-dimethoxy-1,4-phenanthrenequinone (1), was isolated along with a known 9,10-dihydrophenanthrenequinone, ephemeranthoquinone B (2) from an MeOH extract of Odontioda Marie Noel ‘Velano’ through bioassay-guided fractionation. Their structures were elucidated by spectroscopic analysis, and the compounds were tested for in vitro cytotoxic activity. The compounds showed slightly higher cytotoxicity in human oral squamous cell carcinoma and leukemic cell lines as compared with human oral normal cells. The results suggest that apoptosis may not be involved in the cytotoxicity induction.
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  • Ryohei Kobayashi, Kengo Hanaya, Mitsuru Shoji, Kazuo Umezawa, Takeshi ...
    Type: Note
    2012 Volume 60 Issue 9 Pages 1220-1223
    Published: September 01, 2012
    Released: September 01, 2012
    JOURNALS FREE ACCESS
    In order to synthesize the potent nuclear factor (NF)-κB inhibitor, (2S,3S,4S)-dehydroxymethylepoxyquinomycin (DHMEQ), in a large scale, a new route for its corresponding racemic precursor, dihexanoyl (2R*,3R*,4R*)-DHMEQ, was developed. By employing both hydroquinone and benzoquinone intermediates, the total yield, reproducibility, and synthetic steps were improved and the synthetic cost was reduced.
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  • Hiroaki Miyaoka, Yasunori Abe, Etsuko Kawashima
    Type: Note
    2012 Volume 60 Issue 9 Pages 1224-1226
    Published: September 01, 2012
    Released: September 01, 2012
    JOURNALS FREE ACCESS
    The authors described the first synthesis of diterpene isocyanide (−)-kalihinol Y and diterpene isothiocyanate (−)-10-epi-kalihinol I from synthetic intermediates of kalihinol A. The absolute structures of these compounds were confirmed by these syntheses.
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