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Volume 59, Issue 6
Displaying 1-25 of 25 articles from this issue
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Regular Articles
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Masashi Eto, Koki Yamaguchi, Yasuyuki Yoshitake, Kazunobu HaranoArticle type: Regular Article
2011 Volume 59 Issue 6 Pages 681-685
Published: June 01, 2011
Released on J-STAGE: June 01, 2011
JOURNAL FREE ACCESSDensity functional theory (DFT) calculations at the B3LYP/6-31G(d) and B3LYP/6-31G+(d) levels demonstrated that O-furfuryl S-alkyl dithiocarbonate (1) undergoes aromatic [3,3]-sigmatropic rearrangement to the energetically unfavorable S-(2-methylene-2,3-dihydrofuran-3-yl) S-alkyl dithiocarbonate (2′), which then rearranges to furfuryl alkyl sulfide (3) with COS extrusion to regain the aromaticity lost in the first step.View full abstractDownload PDF (1265K) -
Hiroshi Miura, Makoto Kanebako, Hiroyuki Shirai, Hiroshi Nakao, Toshio ...Article type: Regular Article
2011 Volume 59 Issue 6 Pages 686-691
Published: June 01, 2011
Released on J-STAGE: June 01, 2011
JOURNAL FREE ACCESSThe physicochemical characteristics and oral absorption of a poorly water-soluble drug, K-832, adsorbed onto porous silica (Sylysia 350), were compared with those of K-832 adsorbed onto non-porous silica (Aerosil 200). K-832 and silica were treated with supercritical CO2 (scCO2) to produce K-832-Sylysia 350 and K-832-Aerosil 200 formulations. Scanning electron microscopy, polarizing microscopy, powder X-ray diffraction, and differential scanning calorimetry results suggested that K-832 mainly existed in an amorphous state in both formulations. The specific surface area of both formulations was much larger than that of pure K-832 crystals. The dissolution rate of K-832 from both formulations was considerably greater than that from corresponding physical mixtures due to rapid wetting of the hydrophilic carrier surfaces and amorphous state, the dissolution from the K-832-Sylysia 350 formulation being the fastest. In vivo absorption tests on the two formulations indicated no significant differences in their peak concentration (Cmax) and the area under their plasma concentration–time curve (AUC), while the concentrations of K-832 in the K-832-Sylysia 350 formulation were significantly higher than those in the K-832-Aerosil 200 formulation 1 h and 1.5 h after administration of these formulations (p<0.05). This could be attributed to the different dispersion states of K-832 in the formulations due to their different three-dimensional structures (porous and non-porous). In physical stability tests, the amorphous drugs in both formulations were stable at room temperature for at least 14 months. Thus, the absorption of poorly water-soluble drugs could be greatly improved by adsorption onto porous silica using scCO2.View full abstractDownload PDF (5183K) -
Isolation, Characterization and Bioactivity Evaluation of Eighteen Microbial Metabolites of 4′-HydroxyflavanoneJulie Rakel Mikell, Wimal Herath, Ikhlas Ahmad KhanArticle type: Regular Article
2011 Volume 59 Issue 6 Pages 692-697
Published: June 01, 2011
Released on J-STAGE: June 01, 2011
JOURNAL FREE ACCESSFermentation of 4′-hydroxyflavanone (1) with fungal cultures, Beauveria bassiana (ATCC 13144 and ATCC 7159) yielded 6,3′,4′-trihydroxyflavanone (2), 3′,4′-dihydroxyflavanone 6-O-β-D-4-methoxyglucopyranoside (3), 4′-hydroxyflavanone 3′-sulfate (4), 6,4′-dihydroxyflavanone 3′-sulfate (5) and 4′-hydroxyflavanone 6-O-β-D-4-methoxyglucopyranoside (7). B. bassiana (ATCC 13144) and B. bassiana (ATCC 7159) in addition, gave one more metabolite each, namely, flavanone 4′-O-β-D-4-methoxyglucopyranoside (6) and 6,4′-dihydroxyflavanone (8) respectively. Cunninghamella echinulata (ATCC 9244) transformed 1 to 6,4′-dihydroxyflavanone (8), flavanone-4′-O-β-D-glucopyranoside (9), 3′-hydroxyflavanone 4′-sulfate (10), 3′,4′-dihydroxyflavanone (11) and 4′-hydroxyflavanone-3′-O-β-D-glucopyranoside (12). Mucor ramannianus (ATCC 9628) metabolized 1 to 2,4-trans-4′-hydroxyflavan-4-ol (13), 2,4-cis-4′-hydroxyflavan-4-ol (14), 2,4-trans-3′,4′-dihydroxyflavan-4-ol (15), 2,4-cis-3′,4′-dihydroxyflavan-4-ol (16), 2,4-trans-3′-hydroxy-4′-methoxyflavan-4-ol (17), flavanone 4′-O-α-D-6-deoxyallopyranoside (18) and 2,4-cis-4-hydroxyflavanone 4′-O-α-D-6-deoxyallopyranoside (19). Metabolites 13 and 14 were also produced by Ramichloridium anceps (ATCC 15672). The former was also produced by C. echinulata. Structures of the metabolic products were elucidated by means of spectroscopic data. None of the metabolites tested showed antibacterial, antifungal and antiprotozoal activities against selected organisms.View full abstractDownload PDF (778K) -
Jui-Hsin Su, Yi Lu, Wen-Yu Hung, Chiung-Yao Huang, Michael Y. Chiang, ...Article type: Regular Article
2011 Volume 59 Issue 6 Pages 698-702
Published: June 01, 2011
Released on J-STAGE: June 01, 2011
JOURNAL FREE ACCESSFour new nardosinane-type sesquiterpenoids, flavalins E—H (1—4) and two new nornardosinane-type norsesquiterpenoids, flavalins I (5) and J (6), along with five known compounds (7—11) have been isolated from a Formosan soft coral Lemnalia flava. The structures of these compounds were elucidated on the basis of their spectroscopic data. Moreover, the absolute configuration of 10 was further determined by Mosher's method.View full abstractDownload PDF (865K) -
Emma Dichi, Mehrez Sghaier, Bernard Fraisse, François BonhommeArticle type: Regular Article
2011 Volume 59 Issue 6 Pages 703-709
Published: June 01, 2011
Released on J-STAGE: June 01, 2011
JOURNAL FREE ACCESSThis work deals with the preparation and characterization of high-purity nanoparticles of γ-amino n-butyric acid (GABA) in order to enhance the efficiency of this drug. A sublimation procedure at low pressure was applied to GABA after improving the experimental parameters of this physical transformation. The elaboration of the molecule is solvent-free. The process does not change the chemical formula of the compound but modifies its physico-chemical characteristics. In this work, we present the experimental parameters for preparing monoclinic GABA nanoparticles. Their identification and physico-chemical properties were determined with a large number of investigations: Powder X-ray diffraction (PXRD), density and purity measurements, differential scanning calorimetry (DSC), thermo-gravimetric analysis (TGA), calorimetric measurements (ΔHdissolution and Cp), thermally stimulated current (TSC), and electrochemical impedance.View full abstractDownload PDF (1117K) -
Hidetoshi Nakatake, Hisao Ekimoto, Mariko Aso, Atsushi Ogawa, Asami Ya ...Article type: Regular Article
2011 Volume 59 Issue 6 Pages 710-713
Published: June 01, 2011
Released on J-STAGE: June 01, 2011
JOURNAL FREE ACCESSBisphosphonates have high affinity for hydroxyapatite (HA), which is abundantly present in bone. Also, platinum complexes are known that have a wide spectrum of antitumor activities. The conjugate of bisphosphonate and a platinum complex might have HA affinity and antitumor activity, and become a drug for metastatic bone tumor. In this study, the authors synthesized platinum complexes that had dialkyl bisphosphonic acid as a ligand, and evaluated the possibility of the synthesized complexes as a drug for metastatic bone tumor. The synthesized dialkyl bisphosphonate platinum(II) complex was characterized, and its stability in an aqueous solution was also confirmed. The synthesized platinum complex showed higher HA affinity than other platinum complexes such as cisplatin and carboplatin in an experiment of adsorption to HA. In vitro, the platinum complex showed tumor growth inhibitory effect stronger than or equal to cisplatin, which is the most commonly used antitumor agent. Moreover, the platinum complex showed a bone absorption inhibitory effect on the osteoclast. These results suggest potential of dialkyl bisphosphonate platinum(II) complexes as a drug for metastatic bone tumor.View full abstractDownload PDF (568K) -
Hideto Miyabe, Katsuhiko Moriyama, Yoshiji TakemotoArticle type: Regular Article
2011 Volume 59 Issue 6 Pages 714-720
Published: June 01, 2011
Released on J-STAGE: June 01, 2011
JOURNAL FREE ACCESSThe utility of hydroxylamines as nitrogen nucleophiles was investigated in the iridium-catalyzed regio- and enantioselective allylic substitution. Allylic substitution with hydroxylamines proceeded with good enantioselectivities by using the iridium-complex of bis(oxazolinyl)pyridine ligand. The good regio- and enantioselectivities were also achieved in the reaction with alkylamines, p-anisidine, and 4-methoxyphenol.View full abstractDownload PDF (673K) -
Mitsuru Hoshino, Momoka Matsushita, Megumi Samma, Mamiko Asano, Takako ...Article type: Regular Article
2011 Volume 59 Issue 6 Pages 721-724
Published: June 01, 2011
Released on J-STAGE: June 01, 2011
JOURNAL FREE ACCESSSpectrophotometric determination of cobalt(II) was accomplished with vanillilfluorone (VF) in the presence of dimethylbenzyltetradecylammonium chloride (Zephiramine, Zep). In the determination of cobalt(II), Beer's law was obeyed in the range of 24—470 ng/ml, with an effective molar absorption coefficient (at 575 nm) and relative standard deviation of 1.35×105 l mol−1 cm−1 and 0.66% (n=5), respectively. The composition ratio of the colored complex was determined by the mole ratio and continuous variation methods, and it was found to be Co(II) : VF : Zep=1 : 2 : 4. Analysis of cyanocobalamin by the same procedure showed that cyanocobalamin could be determined in the concentration range of 0.5—0.11 μg/ml using the proposed method.View full abstractDownload PDF (589K) -
Mamdouh Nabil Samy, Hany Ezzat Khalil, Sachiko Sugimoto, Katsuyoshi Ma ...Article type: Regular Article
2011 Volume 59 Issue 6 Pages 725-729
Published: June 01, 2011
Released on J-STAGE: June 01, 2011
JOURNAL FREE ACCESSThree new flavonoid glycosides, demethoxycentaureidin 7-O-β-D-galacturonopyranoside, pectolinarigenin 7-O-α-L-rhamnopyranosyl-(1‴→4″)-β-D-glucopyranoside and 7-O-α-L-rhamnopyranosyl-(1‴→4″)-β-D-glucuronopyranoside, a new megastigmane glucoside, byzantionoside B 6′-O-sulfate, and a new (Z)-hex-3-en-1-ol O-β-D-xylopyranosyl-(1″→2′)-β-D-glucopyranoside, were isolated from leaves of Ruellia patula JACQ., together with 12 known compounds, β-sitosterol glucoside, vanilloside, bioside (decaffeoyl verbascoside), acteoside (verbascoside), syringin, benzyl alcohol O-β-D-xylopyranosyl-(1″→2′)-β-D-glucopyranoside, cistanoside E, roseoside, phenethyl alcohol O-β-D-xylopyranosyl-(1″→2′)-β-D-glucopyranoside, (+)-lyoniresinol 3α-O-β-D-glucopyranoside, isoacteoside and 3,4,5-trimethoxyphenol O-α-L-rhamnopyranosyl-(1″→6′)-β-D-glucopyranoside. Their structures were elucidated by means of spectroscopic analyses.View full abstractDownload PDF (556K) -
Rashad Al-Salahi, Detlef Geffken, Maria KoellnerArticle type: Regular Article
2011 Volume 59 Issue 6 Pages 730-733
Published: June 01, 2011
Released on J-STAGE: June 01, 2011
JOURNAL FREE ACCESSThis research was carried out to study the pharmacological activity of a newly synthesized series of 2-alkoxy-[1,2,4]triazolo[1,5-a]quinazolin-5-ones as adenosine receptor antagonists. These compounds have been tested in radioligand binding assays on cloned Chinese hamster ovary (CHO) cells transfected with A1, A2A, A2B and A3 receptors. In particular, among the triazoloquinazolines (1—11), the dialkoxy derivative (7b) was found to have the highest affinity at A1 subtype receptor, and its radioligand binding activity together with 1,3-dipropyl-8-cyclopentylxanthine (DPCPX) was studied. Finally, the structure–activity relationship (SAR) studies on the titled compounds provide some new insights about steric hindrance and lipophilic requirements for anchoring to the adenosine receptors recognition site.View full abstractDownload PDF (597K) -
Jianjun Zhang, Yuan Gao, Feng Su, Zhenhua Gong, Yihua ZhangArticle type: Regular Article
2011 Volume 59 Issue 6 Pages 734-741
Published: June 01, 2011
Released on J-STAGE: June 01, 2011
JOURNAL FREE ACCESSZCVI4-2 is a newly developed furoxan-based nitric oxide-releasing derivative of oleanolic acid. It exhibited strong cytotoxicity against human hepatocellular carcinoma (HCC) in vitro and significantly inhibited the growth of HCC tumors in vivo. However, its low aqueous solubility and toxicity due to the fast release of nitric oxide (NO) in blood challenged its formulation. In the present investigation, the interaction characteristics of ZCVI4-2 with bovine serum albumin (BSA) were studied by fluorescence spectrometry, synchronous fluorescence spectra and Fourier transform-infrared (FT-IR). It was found that ZCVI4-2 concentration, temperature and pH had significant effect on the interactions. ZCVI4-2 was able to bind BSA with high affinity, low temperature and neutral pH favor the binding. The interaction exhibited to be a spontaneous and exothermic process. ZCVI4-2 was buried in the hydrophobic pocket in subdomain IIB of BSA and the exact binding site was around 3.83 nm in average from Trp212. The NO releasing characteristics of nanocomplexes were compared with ZCVI4-2 solution by Griess Reagent Method. It was found that the release of NO from ZCVI4-2/BSA nanocomplexes was retarded significantly, thus making ZCVI4-2 into a BSA-bound nanocomplexes had the great potential to lower the toxicity due to the absence of organic solvents and surfactants and meanwhile the sustained release of NO.View full abstractDownload PDF (958K)
Notes
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So Young Lee, Ju Sun Kim, Ran Joo Choi, Yeong Shik Kim, Je-Hyun Lee, S ...Article type: Note
2011 Volume 59 Issue 6 Pages 742-746
Published: June 01, 2011
Released on J-STAGE: June 01, 2011
JOURNAL FREE ACCESSA new minor polyoxygenated triterpene named glutinolic acid (1) and two new aeginetic acid quinovosides (2, 3) were isolated from the roots of Rehmannia glutinosa LIBOSCH. (Scrophulariaceae) cultivated in Gunwi-gun, Korea. The structures of these compounds were established as 3α,19α,20β,24,30-pentahydroxyurs-12-en-28-oic acid (1, glutinolic acid), aeginetic acid 5-O-β-D-quinovoside (2) and aeginetoyl ajugol 5″-O-β-D-quinovoside (3) on the basis of chemical and spectroscopic evidence.View full abstractDownload PDF (729K) -
Teigo Asai, Takaomi Sakai, Kiyoshi Ohyama, Yoshinori FujimotoArticle type: Note
2011 Volume 59 Issue 6 Pages 747-752
Published: June 01, 2011
Released on J-STAGE: June 01, 2011
JOURNAL FREE ACCESSChemical investigation of the glandular trichome exudate from Geranium carolinianum L. (Geraniaceae) led to the characterization of unique disaccharide derivatives, n-octyl 4-O-isobutyryl-α-L-rhamnopyranosyl-(1→2)-6-O-isobutyryl-β-D-glucopyranoside (1), n-octyl 4-O-isobutyryl-α-L-rhamnopyranosyl-(1→2)-6-O-(2-methylbutyryl)-β-D-glucopyranoside (2) and n-octyl 4-O-(2-methylbutyryl)-α-L-rhamnopyranosyl-(1→2)-6-O-isobutyryl-β-D-glucopyranoside (3), named caroliniasides A—C, respectively. These structures were determined by spectral means. n-Alkyl glycoside derivatives have been isolated from the glandular trichome exudates for the first time. This rare type of secondary metabolites could be applicable to chemotaxonomic perspective because they are found in glandular trichome exudates of plants belonging to the genus Geranium, according to our studies.View full abstractDownload PDF (610K) -
Tetsutaro Kimachi, Eri Torii, Yusuke Kobayashi, Misae Doe, Motoharu Ju ...Article type: Note
2011 Volume 59 Issue 6 Pages 753-756
Published: June 01, 2011
Released on J-STAGE: June 01, 2011
JOURNAL FREE ACCESSSynthesis of dehydoriso-β-lapachone (1) in both racemic and enantioenriched forms is achieved starting from reduced naphthoquinone equivalents. As for the synthesis of enantioenriched dehydroiso-β-lapachone, introduction of the asymmetric center was carried out by catalytic asymmetric epoxidation of the unfunctionalized trisubstituted olefin using Shi epoxidation diketal catalyst. The construction of isopropenylfurano-1,2-(β)-naphthoquinone was carried out by acidic ring-opening reaction of the epoxynaphthalene and the following diammonium cerium(IV) nitrate (CAN) oxidation. The absolute configuration of naturally occurring (−)-dehydroiso-β-lapachone was finally determined as (R) by comparing the measured optical rotation value of the synthetic (R)-dehydroiso-β-lapachone.View full abstractDownload PDF (604K) -
Jung Im Lee, Youngwan SeoArticle type: Note
2011 Volume 59 Issue 6 Pages 757-761
Published: June 01, 2011
Released on J-STAGE: June 01, 2011
JOURNAL FREE ACCESSSix meroterpenoids (compounds 1—6) of chromene class, including three known compounds (1—3), were isolated from Sargassum siliquastrum. The structure of these compounds was established by extensive 2D-NMR experiments such as 1H gradient double quantum filtered correlation spectroscopy (gDQCOSY), total correlation spectroscopy (TOCSY), nuclear Overhauser effect spectroscopy (NOESY), gradient heteronuclear multiple quantum coherence (gHMQC), and gradient heteronuclear multiple bond correlation (gHMBC), and by comparison with published spectral data. The antioxidant activity of these compounds was evaluated by various antioxidant tests, such as scavenging effects on generation of intracellular reactive oxygen species (ROS), increments of intracellular glutathione (GSH) level, and inhibitory effects on lipid peroxidation in human fibrosarcoma HT 1080 cells. Compounds (1—6) significantly decreased generation of intracellular ROS and inhibited lipid peroxidation while they increased levels of intracellular GSH at a concentration of 5 μg/ml.View full abstractDownload PDF (581K) -
Huinan Zhou, Tianjiao Zhu, Shengxin Cai, Qianqun Gu, Dehai LiArticle type: Note
2011 Volume 59 Issue 6 Pages 762-766
Published: June 01, 2011
Released on J-STAGE: June 01, 2011
JOURNAL FREE ACCESSFive new drimane sesquiterpenes (1—5) together with 14 known analogues (6—19) were isolated from laboratory cultures of a mangrove-derived fungus Aspergillus ustus. Their structures were established by spectroscopic methods and antitumor activities were evaluated by sulforhodamine B (SRB) and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) methods.View full abstractDownload PDF (598K) -
Junichi Shinozaki, Takahisa Nakane, Naoe Onodera, Akihito Takano, Kazu ...Article type: Note
2011 Volume 59 Issue 6 Pages 767-769
Published: June 01, 2011
Released on J-STAGE: June 01, 2011
JOURNAL FREE ACCESSLactucenyl acetate (1), a new member of migrated lupane triterpenoids was isolated from Lactuca indica and its structure was elucidated on the basis of spectral analyses. The structure of tarolupenyl acetate was revised as lup-19(21)-en-3β-yl acetate (2).View full abstractDownload PDF (523K) -
Li-feng Zan, Jian-chun Qin, Ya-mei Zhang, Yan-hua Yao, Hai-ying Bao, X ...Article type: Note
2011 Volume 59 Issue 6 Pages 770-772
Published: June 01, 2011
Released on J-STAGE: June 01, 2011
JOURNAL FREE ACCESSTwo natural antioxidants, named inonotusin A (1) and B (2), were isolated from the methanolic extract of the fruit bodies of Inonotus hispidus, together with (E)-4-(3,4-dihydroxyphenyl)but-3-en-2-one (3), hispidin (4) and 3,4-dihydroxybenzaldehyde (5). Their structures were identified by means of extensive NMR and MS data analysis. Compounds 1, 2 and 4 exhibited significant scavenging activity against the 2,20-azinobis(3-ethylbenzhiazoline-6-sulfonate) (ABTS) radical cation. Compound 1 also showed moderate cytotoxicity against a human breast carcinoma cell line (MCF-7) with IC50 values of 19.6 μM.View full abstractDownload PDF (548K) -
Il Kyun Lee, Ki Hyun Kim, Seung Young Lee, Sang Un Choi, Kang Ro LeeArticle type: Note
2011 Volume 59 Issue 6 Pages 773-777
Published: June 01, 2011
Released on J-STAGE: June 01, 2011
JOURNAL FREE ACCESSThree new megastigmane glucopyranosides, komaroveside A [(3S,4R,5Z,7E)-3,4-dihydroxy-5,7-megastigmadien-9-one-3-O-β-D-glucopyranoside] (1), komaroveside B [(3S,4S,5S,6R,7E)-5,6-epoxy-3,4-dihydroxy-7-megastigmen-9-one-3-O-β-D-glucopyranoside] (2) and komaroveside C [(3S,4S,5S,6R,7E,9S)-5,6-epoxy-3,4,9-trihydroxy-7-megastigmen-3-O-β-D-glucopyranoside] (3) were isolated, together with eight known compounds, from Cardamine komarovii. The identification of these compounds and the elucidation of their structures were based on 1D- and 2D-NMR spectral data analysis. The isolated compounds were tested for their cytotoxicity against four human tumor cell lines (A549, SK-OV-3, SK-MEL-2, HCT15) in vitro using the sulforhodamine B bioassay.View full abstractDownload PDF (725K) -
Consolacion Yasaña Ragasa, Dinah Lorenzana Espineli, Chien-Chan ...Article type: Note
2011 Volume 59 Issue 6 Pages 778-782
Published: June 01, 2011
Released on J-STAGE: June 01, 2011
JOURNAL FREE ACCESSThe leaves of Barringtonia asiatica afforded two new triterpenes, germanicol caffeoyl ester (1) and camelliagenone (2). Their structures were elucidated by extensive 1D- and 2D-NMR spectroscopy. It also afforded germanicol trans-coumaroyl ester (3), germanicol cis-coumaroyl ester (4), germanicol (5), camelliagenin A (6), spinasterol, sitosterol, squalene, lutein and trilinolein. Compounds 3, spinasterol and trilinolein were isolated from the fruits, while the seeds yielded spinasterol, squalene, linoleic acid and trilinolein. Compounds 1—5 exhibited antifungal activity against Candida albicans, 1—3 and 5 showed antibacterial activity against Staphylococcus aureus, while 5 is active against Pseudomonas aeruginosa.View full abstractDownload PDF (602K) -
Hitoshi Nakayama, Yuka Morita, Hirohiko Kimura, Keiichi Ishihara, Sato ...Article type: Note
2011 Volume 59 Issue 6 Pages 783-786
Published: June 01, 2011
Released on J-STAGE: June 01, 2011
JOURNAL FREE ACCESSA series of N-(trifluoromethyl-2-pyridinyl)alkane- and arenesulfonamides 2—5 have been synthesized by the substitution reaction of 2-chloro(trifluoromethyl)pyridines 6 with alkane- and arenesulfonamides 7. Their inhibitory activities against secretory phospholipase A2 of porcine pancreas were examined and the analog N-[4,5-bis(trifluoromethyl)-2-pyridinyl]-4-trifluoromethylbenzenesulfonamide 4i was shown to have the highest inhibitory activity, with an IC50 value of 0.58 mM.View full abstractDownload PDF (539K) -
Masashi Yokoya, Hiroshi Ito, Naoki SaitoArticle type: Note
2011 Volume 59 Issue 6 Pages 787-792
Published: June 01, 2011
Released on J-STAGE: June 01, 2011
JOURNAL FREE ACCESSA nine-step synthesis of pentacyclic key intermediate 11 of cribrostatin 4 (2) along with renieramycin I (1i) from 3,6-bisarylpiperazine-2,5-dione derivative 3 is described. The key step of this synthesis is the stereoselective cyclization of lactam nitrogen with diethoxyethyl benzoate, followed by the stereoselective hydrogenation to generate ABC ring system 6.View full abstractDownload PDF (1036K) -
Shuji Kitagawa, Kenta Yoshii, Shin-ya Morita, Reiko TeraokaArticle type: Note
2011 Volume 59 Issue 6 Pages 793-796
Published: June 01, 2011
Released on J-STAGE: June 01, 2011
JOURNAL FREE ACCESSWe examined the intradermal delivery of a hydrophilic polyphenol chlorogenic acid by in vitro study using excised guinea pig dorsal skin and Yucatan micropig skin. Skin accumulation as well as the solubility of chlorogenic acid in aqueous vehicles was much greater than for other polyphenols such as quercetin and genistein. However, since enhancement of skin delivery seemed to be necessary to exhibit its protective effects against oxidative damage of skin, we examined the effects of microemulsions as vehicles. Using microemulsions consisting of 150 mM NaCl solution, isopropyl myristate, polyoxyethylene sorbitan monooleate (Tween 80) and ethanol, skin accumulation as well as solubility of chlorogenic acid further increased. Enhancement effect of an oil-in-water (o/w-type) microemulsion was greater than that of a water-in-oil (w/o-type) microemulsion possibly due to the greater increase in solubility. This finding was quite different from previous findings on relatively hydrophobic polyphenols such as quercetin and genistein. Pretreatment of guinea pig dorsal skin with chlorogenic acid containing microemulsion gel prevented erythema formation induced by UV irradiation. These findings indicate the potential use of hydrophilic chlorogenic acid with o/w-type microemulsion as a vehicle to protect skin against UV-induced oxidative damage.View full abstractDownload PDF (5006K) -
Masakazu Kogami, Nobuhide WatanabeArticle type: Note
2011 Volume 59 Issue 6 Pages 797-798
Published: June 01, 2011
Released on J-STAGE: June 01, 2011
JOURNAL FREE ACCESSA safe and efficient process for the preparation of ethyl 2-methylthiophene-3-carboxylate (5) was devised. This process provides several advantages over the precedents, involving operational simplicity, avoidance of the use of strong bases such as n-butyllithium and application of noncryogenic conditions, and enabled to prepare 5 in 52% overall yield from commercially available 2-methylthiophene on a multikilogram scale.View full abstractDownload PDF (441K)
Communication to the Editor
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Mingyu Jiao, Hirofumi Matsunaga, Tadao IshizukaArticle type: Communication to the Editor
2011 Volume 59 Issue 6 Pages 799-801
Published: June 01, 2011
Released on J-STAGE: June 01, 2011
JOURNAL FREE ACCESSA simple and inexpensive system comprised of H2O2-pyridine-FeCl3·6H2O for the catalysis of olefin epoxidation was established. Intriguingly, the reactivity of this system greatly depends on the amounts of pyridine. Various substrates, including aromatic and aliphatic olefins, were epoxidized by this simple system in moderate to excellent yields.View full abstractDownload PDF (492K)
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