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Volume 59, Issue 3
Displaying 1-22 of 22 articles from this issue
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Regular Articles
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Mitsuo Miyazawa, Yumi Kawauchi, Yoshiharu Okuno, Yoshimitsu OdaArticle type: Regular Article
2011 Volume 59 Issue 3 Pages 295-297
Published: March 01, 2011
Released on J-STAGE: March 01, 2011
JOURNAL FREE ACCESSNicotine is the primary psychoactive component in tobacco. It is taken into the body by tobacco smoking, and mainly metabolized to cotinine in the hepatic cytochrme P450 (CYP) 2A6. The objective of this study was to develop a sensitive method for the determination of nicotine metabolism to cotinine using HPLC. The internal standard, trans-4′-carboxycotinine methyl ester was synthesized with a simple method. The nicotine and cotinine were separated completely and detected by C18 5-μm analytical column (L-column Octa decyl silyl (ODS), 150 mm×4.6 mm i.d.) equipped with a C18 5-μm guard column (L-column ODS, 10 mm×4.6 mm i.d.) and ultraviolet detection at 260 nm. The detection limit of the assay was 0.05 μM for cotinine (n=5, R.S.D) and 0.1 μM for nicotine. Thus the present results provided a sensitive and useful method for the determination of nicotine metabolism catalyzed by CYP2A6.View full abstractDownload PDF (591K) -
Kohei Tahara, Takeshi Sakai, Hiromitsu Yamamoto, Hirofumi Takeuchi, Na ...Article type: Regular Article
2011 Volume 59 Issue 3 Pages 298-301
Published: March 01, 2011
Released on J-STAGE: March 01, 2011
JOURNAL FREE ACCESSThis study sought to evaluate the in vitro transfection efficiency of plasmid DNA (pDNA)-loaded chitosan-modified poly(DL-lactide-co-glycolide) nanospheres (CS-PLGA NS) in a gene-delivery system. Using the emulsion solvent diffusion (ESD) method, pDNA-loaded PLGA NS was prepared and the surface of the PLGA NS was modified by binding to CS. Gene transfection ability of CS-PLGA NS was examined in A549 cells. The luciferase gene was used as a reporter gene. The pattern of luciferase activity by pDNA-loaded CS-PLGA NS was initially weak, but gradually grew stronger before decreasing activity. These phenomena should be in accordance with the sustained-release profile of pDNA from PLGA NS in the cytosol and the pDNA protection against DNase. Positively charged CS-PLGA NS was found, by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt (MTS) assay, not to exhibit cytotoxicity on A549 cells. These results suggest that CS-PLGA NS are potential contributors to efficient pDNA delivery due to their increased interactions with cells and lack of cytotoxic effects.View full abstractDownload PDF (632K) -
Xing-Ri Cui, Ryota Saito, Takatsugu Kubo, Daijiro Kon, Yuich Hirano, S ...Article type: Regular Article
2011 Volume 59 Issue 3 Pages 302-314
Published: March 01, 2011
Released on J-STAGE: March 01, 2011
JOURNAL FREE ACCESSChrysophanol and 1,8-di-O-hexylchrysophanol derivatives having nucleic acid bases at position 5 were synthesized. Furthermore, derivatives of menadione substituted at position 11 (type A naphthoquinone derivatives) or methylmenadione substituted at position 7 (type B naphthoquinone derivatives) modified with nucleic acid bases, amines and thiocyano, selenocyano or thioacetyl groups were synthesized. The cytotoxic effects of these derivatives on HCT 116 cells, which poorly express P-glycoprotein (P-gp), and Hep G2 cells, which stably express P-gp, were evaluated by performing 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Results were compared with those obtained using 5-fluorouracil (5-FU), which has been used clinically. Several of these derivatives exhibited markedly higher potent cytotoxic effects not only on HCT cancer cells but also Hep G2 cancer cells as compared with 5-FU.View full abstractDownload PDF (1066K) -
Archana Mehrotra, Ramesh Chand Nagarwal, Jayanta Kumar PanditArticle type: Regular Article
2011 Volume 59 Issue 3 Pages 315-320
Published: March 01, 2011
Released on J-STAGE: March 01, 2011
JOURNAL FREE ACCESSThe aim of this work was to prepare chitosan nanoparticles loaded with antineoplastic drug Lomustine (LCNPs), by ionic-gelation method with homogenization. The nanoparticles were characterized for particle size, polydispersity index (PDI), surface morphology, encapsulation efficiency, in-vitro drug release and cytotoxicity on human lung cancer cell line L132 by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The particle size, zeta potential and encapsulation efficiency of prepared nanoparticles ranged from 75±1.1 to 637±1.6 nm (PDI from 0.05±0.001 to 0.18±0.007), 37.2±0.21 to 53.8±0.18 mV and 66.74±1.4 to 98.0±1.8% respectively. The particles were spherical in shape with smooth surface in scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images. Mechanical shearing by homogenization treatment significantly changed the nanoparticle size. The drug release rate was biphasic and diffusion controlled over the 8 h. LCNPs greatly inhibited the growth of the L132 cancer cell line used in this study in comparison to the native Lomustine (LMT).View full abstractDownload PDF (1672K) -
Xue-Jun Xia, Rui-Fang Guo, Yu-Ling Liu, Peng-Xiao Zhang, Cui-Ping Zhou ...Article type: Regular Article
2011 Volume 59 Issue 3 Pages 321-326
Published: March 01, 2011
Released on J-STAGE: March 01, 2011
JOURNAL FREE ACCESSThe objective of this paper was to develop a novel Cremophor-free, autoclave stable, intravenous emulsion for paclitaxel (PACE). A paclitaxel–cholesterol complex was used as the drug carrier to improve the solubility of paclitaxel in the oil phase of emulsions. The complex and PACE were prepared by rotary evaporation and high-pressure homogenization, respectively. Effects of oil phases, emulsifiers and pH values on the characteristics of PACE were investigated. PACE was characterized with regard to its appearance, morphology, osmolality, pH value, particle size, zeta potential, encapsulation efficiency and stability. Hypersensitivity was evaluated by guinea pig hypersensitivity reaction. The final formulation was composed of the complex, soybean oil, medium-chain triglyceridel, soybean lecithin, poloxamer 188 and glycerol. The resulting PACE had an encapsulation efficiency of 97.3% with a particle size of 135 nm and a zeta potential of −38.3 mV. Osmolality and pH of the formulation were 383 mOsmol/kg and 4.5, respectively. The formulation survived autoclaving at 115 °C for 30 min and remained stable for at least 12 months at 6 °C. PACE also exhibited a better tolerance than an equal dose of Cremophor-based paclitaxel injection in guinea pigs, as no obvious hypersensitivity reaction was observed. These results suggested that PACE has a great potential for industrial-scale production and clinical applications.View full abstractDownload PDF (1460K) -
Ranju Bansal, Sheetal Guleria, Sridhar Thota, Rolf Wolfgang Hartmann, ...Article type: Regular Article
2011 Volume 59 Issue 3 Pages 327-331
Published: March 01, 2011
Released on J-STAGE: March 01, 2011
JOURNAL FREE ACCESSTaking into consideration the structural requirements for cytotoxicity and aromatase inhibition, several new 16E-arylidenosteroidal derivatives have been prepared and evaluated for their cytotoxic and aromatase inhibitory activity. The new steroidal analogues 3, 5—8 and 11 exhibited significant cytotoxic effects when screened against three cancer cell lines, MCF-7 (breast), NCl-H460 (lung) and SF-268 central nervous system (CNS) at 100 μM and sensible cytotoxic effects subsequently in sixty cancer cell lines derived from nine cancers types (leukemia, lung, colon, CNS, melanoma, ovarian, renal, prostate and breast cancers). The imidazolyl substituted steroidal derivatives 5 and 7 exhibited strong inhibition of the aromatase enzyme with 16-[4-{3-(imidazol-1-yl)propoxy}-3-methoxybenzylidene]-5-androstene-3β,17β-diol (7) displaying 13 times more potency in comparison to aminoglutethimide.View full abstractDownload PDF (579K) -
Masato Nishikawa, Yoshinori Onuki, Yoshihide Okuno, Kozo TakayamaArticle type: Regular Article
2011 Volume 59 Issue 3 Pages 332-337
Published: March 01, 2011
Released on J-STAGE: March 01, 2011
JOURNAL FREE ACCESSThis study investigated the relationship between the state of water and the dispersion stability of a skin cream formulation. Hydrophilic ointments treated with a high-pressure wet-type jet mill were used as model formulations. Spin–lattice relaxation times (T1) were measured by magnetic resonance techniques to estimate the state of water in samples. A shorter T1 relaxation time was obtained from samples with higher surfactant content, whereas the processing pressure of the jet mill and 1-week storage at 40 °C did not influence the T1 relaxation time. Observations using scanning electron microscopy (SEM) showed that coalescence occurred in samples with lower surfactant contents (1.0% by weight) following 1-week storage at 40 °C. We also investigated samples prepared using a hydrophilic surfactant with a short polyethylene glycol (PEG) chain and with PEG-4000. From the change in T1 relaxation times after removing the oil phase from samples by centrifugation, it was clarified that most of the surfactant was located on the surface of oil droplets. Furthermore, SEM observations showed that phase separation was facilitated as the PEG chain length of the surfactant shortened. Thus, a thin water layer over oil droplets is the most important factor for stabilizing their dispersion. This study provides proof-of-principle results on the contribution of the state of water to the dispersion stability of a skin cream formulation.View full abstractDownload PDF (2177K) -
Lin Wang, Guang-Ying Chen, Chang-Ri Han, Yuan Yuan, Biao Yang, Yuan Zh ...Article type: Regular Article
2011 Volume 59 Issue 3 Pages 338-340
Published: March 01, 2011
Released on J-STAGE: March 01, 2011
JOURNAL FREE ACCESSTwo novel alkaloids, saprosmine A (1) and saprosmine B (2), were isolated from the stem of Saprosma hainanense MERR., along with five known alkaloids: marcanine A (3); cleistopholine (4); 4-methoxycarbonyl-5,10-benzogquinolinequinone (5); liriodenine (6); and quinoline (7). The chemical structures were established on the basis of extensive spectroscopic (IR, 1D-NMR, 2D-NMR, MS) data analysies and by comparison with spectroscopic data reported in the literature. Compounds 1 to 6 were evaluated for in vitro cytotoxic activities against the SPC-A-1 (human lung cancer), BEL-7402 (human hepatocellular carcinoma), SGC-7901 (human gastric cancer), and K-562 (human myelogenous leukaemia) cancer cell lines. Compounds 1 and 2 exhibited weak cytotoxic activities against K-562 cells. Compounds 3 and 5 showed cytotoxic activities against all four cancer cell lines.View full abstractDownload PDF (489K) -
Jun-ichi Kuroyanagi, Kazuo Kanai, Takao Horiuchi, Hiroshi Takeshita, S ...Article type: Regular Article
2011 Volume 59 Issue 3 Pages 341-352
Published: March 01, 2011
Released on J-STAGE: March 01, 2011
JOURNAL FREE ACCESSA series of 1,3-benzoxazole-4-carbonitriles was synthesized and evaluated for its antifungal activity, solubility, and metabolic stability. Among those compounds, 4-cyano-N,N,5-trimethyl-7-[(3S)-3-methyl-3-(methylamino)pyrrolidin-1-yl]-6-phenyl-1,3-benzoxazole-2-carboxamide (16b) exhibited potent in vitro activity against Candida species, higher water solubility, and improved metabolic stability compared to lead compound 1. Compound 16b showed potent in vivo efficacy against mice Candida infection models and good bioavailability in rats.View full abstractDownload PDF (940K) -
Yung-Husan Chen, Chia-Ying Tai, Yueh-Hsiung Kuo, Chia-Ying Kao, Jan-Ju ...Article type: Regular Article
2011 Volume 59 Issue 3 Pages 353-358
Published: March 01, 2011
Released on J-STAGE: March 01, 2011
JOURNAL FREE ACCESSFive new eunicellin-type diterpenoids, cladieunicellins A—E (1—5), were isolated from an Indonesian soft coral identified as Cladiella sp. The structures of diterpenoids 1—5 were established using spectroscopic methods. Eunicellins 2 and 5 were found to be cytotoxic against DLD-1 and HL-60 tumor cells, respectively, and 3 displayed inhibitory effects against superoxide anion generation by human neutrophils.View full abstractDownload PDF (666K) -
Wei-Hua Jiao, Hao Gao, Feng Zhao, Hou-Wen Lin, Yu-Min Pan, Guang-Xiong ...Article type: Regular Article
2011 Volume 59 Issue 3 Pages 359-364
Published: March 01, 2011
Released on J-STAGE: March 01, 2011
JOURNAL FREE ACCESSDuring further chemical and biological investigations of Picrasma quassioides BENNET, four new bis-β-carboline alkaloids, quassidines E—H (1—4), and three new β-carboline alkaloids, canthin-16-one-14-butyric acid (5), 3-(1,1-dimethoxylmethyl)-β-carboline (6), and 6,12-dimethoxy-3-formyl-β-carboline (7), were isolated from its anti-inflammatory CHCl3-soluble fraction. Structures of new compounds were elucidated and characterized by MS and NMR analysis. A plausible biogenetic pathway for quassidine E (1), the first bis-β-carboline alkaloid in which a canthin-6-one moiety and a β-carboline moiety were connected together by a single carbon–carbon bond from the nature, was proposed. Quassidines E—G (1—3) showed potent inhibitory activity on the production of nitric oxide (NO), tumor necrosis factor α (TNF-α), or interleukin 6 (IL-6) in mouse monocyte-macrophage RAW264.7 cells stimulated by lipopolysaccharide (LPS). Analysis of anti-inflammatory activity of all β-carboline and bis-β-carboline alkaloids from P. quassioides showed that the carbonyl groups or double carbon–carbon bonds at C-14 for β-carbolines and C-14′ for bis-β-carbolines were bioactive groups for their in vitro anti-inflammatory activity. Structure–activity relationship of these compounds on inhibitory activity of the three inflammatory cytokines was discussed.View full abstractDownload PDF (724K) -
Hisashi Matsuda, Seikou Nakamura, Junko Iwami, Xuezheng Li, Yutana Pon ...Article type: Regular Article
2011 Volume 59 Issue 3 Pages 365-370
Published: March 01, 2011
Released on J-STAGE: March 01, 2011
JOURNAL FREE ACCESSThe methanolic extract and its EtOAc-soluble fraction from the rhizomes of Zingiber cassumunar inhibited invasion of human fibrosarcoma HT 1080 cells. From the EtOAc-soluble fraction, eight new phenylbutanoids, cassumunols A—H, were isolated together with 30 known constituents. The structures of new phenylbutanoids were elucidated on the basis of chemical and physicochemical evidence. Principal constituents were examined the inhibitory effects on the invasion of HT 1080 cells. Among them, phlain I and III, (E)-1-(3,4-dimethoxyphenyl)buta-1,3-diene, (E)-1-(2,4,5-trimethoxyphenyl)buta-1,3-diene, and (−)-β-sesquiphellandrene showed anti-invasion effects. Interestingly, (E)-1-(2,4,5-trimethoxyphenyl)buta-1,3-diene [inhibition (%) 46.8±7.2 (p<0.05) at 30 μM] significantly inhibited the invasion, and only a weak cytotoxic effect was observed.View full abstractDownload PDF (666K)
Notes
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Ming Zhao, Liming Bai, Asami Toki, Ryo Hasegawa, Jun-ichi Sakai, Toshi ...Article type: Note
2011 Volume 59 Issue 3 Pages 371-377
Published: March 01, 2011
Released on J-STAGE: March 01, 2011
JOURNAL FREE ACCESSA new cardenolide diglycoside (1) was isolated from Nerium oleander together with ten known cardenolide diglycosides 2—11. The structure of compound 1 was established on the basis of their spectroscopic data. The in vitro anti-inflammatory activity of compounds 1—11 was examined on the basis of inhibitory activity against the induction of the intercellular adhesion molecule-1 (ICAM-1). Compounds 2—5 were active at an IC50 value of less than 0.8 μM. The cytotoxicity of compounds 1—11 was evaluated against three human cell lines normal human fibroblast cells (WI-38), malignant tumor cells induced from WI-38 (VA-13), and human liver tumor cells (HepG2). Compound 3 was active toward VA-13 cells, and compounds 2—5 were active toward HepG2 cells at IC50 values of less than 1.3 μM. The multidrug resistance (MDR)-reversal activity of compounds 1—11 was evaluated on the basis of the amount of calcein in MDR human ovarian cancer 2780AD cells in the presence of each compound. Compounds 1 and 8 showed moderate effects on calcein accumulation.View full abstractDownload PDF (839K) -
Takashi Kikuchi, Hiroyuki Akazawa, Keiichi Tabata, Aranya Manosroi, Ji ...Article type: Note
2011 Volume 59 Issue 3 Pages 378-381
Published: March 01, 2011
Released on J-STAGE: March 01, 2011
JOURNAL FREE ACCESSEleven triterpene acids, 1—11, isolated from the leaves of Eriobotrya japonica, were evaluated for inhibition of DNA topoisomerase (Topo) I and cytotoxicity against human leukemia (HL60) and melanoma cell lines (CRL1579). Among the compounds tested, four compounds, δ-oleanolic acid (4), ursolic acid (5), 3-O-(E)-p-coumaroyl tormentic acid (8), and betulinic acid (10), exhibited potent Topo I inhibitory activity (IC50 20.3—36.5 μM) and cytotoxicity against HL60 (EC50 5.0—8.1 μM). Upon assessing the apoptosis-inducing activity in HL60 cells, compound 8 exhibited induction of apoptosis detected by the observation of DNA fragmentation and membrane phospholipid exposure in flow cytometry. Western blot analysis showed that compound 8 markedly reduced the levels of procaspases-3 and 9, while being increased the levels of cleaved caspases-3 and 9. On the other hand, compound 8 exerted almost no influence on the expression of caspase-8. In addition, compound 8 increased significantly Bax/Bcl-2 ratio and activated caspase-2. These results suggested that compound 8 induced apoptotic cell death in HL60 via mainly mitochondrial pathway by, at least in part, Topo I inhibition. Therefore, compound 8 may be promising lead compound for developing an effective drug for treatment of leukemia.View full abstractDownload PDF (1144K) -
Piseth Khiev, Sei-Ryang Oh, Hee-Sung Chae, Ok-Kyoung Kwon, Kyung-Seop ...Article type: Note
2011 Volume 59 Issue 3 Pages 382-384
Published: March 01, 2011
Released on J-STAGE: March 01, 2011
JOURNAL FREE ACCESSBioactivity-guided isolation on a n-hexane-soluble fraction of Thyrsanthera suborbicularis led to the isolation of a new rosane-type diterpene, 19-hydroxy-1(10), 15-rosadiene (1), along with three known compounds, taraxerol, acetyl aleuritolic acid, and spathulenol. The structures of isolated compounds were determined by interpretation of NMR spectroscopic data and mass spectrometry. Compound 1 demonstrated significantly inhibitory activity on nitric oxide production in RAW264.7 lipopolysaccharide (LPS)-activated mouse macrophages with an IC50 value of 2.91 μg/ml via the suppression of inducible nitric oxide synthase (iNOS) mRNA expression.View full abstractDownload PDF (578K) -
Thanesuan Nuanyai, Ruengrit Sappapan, Tirayut Vilaivan, Khanitha Pudho ...Article type: Note
2011 Volume 59 Issue 3 Pages 385-387
Published: March 01, 2011
Released on J-STAGE: March 01, 2011
JOURNAL FREE ACCESSFour new cycloartane triterpenes, named gardenoins E—H (1—4), were isolated from the apical buds of Gardenia obtusifolia, together with five known cycloartanes. Only compound 1 displayed cytotoxicity against colon, hepatic and lung cancer cell lines.View full abstractDownload PDF (616K) -
Yoshimitsu Yamazaki, Yasuhiro KawanoArticle type: Note
2011 Volume 59 Issue 3 Pages 388-391
Published: March 01, 2011
Released on J-STAGE: March 01, 2011
JOURNAL FREE ACCESSIt is beneficial to treat chronic inflammatory condition in patients through diets that inhibit the production of proinflammatory cytokines and mediators such as tumor necrosis factor-α (TNF-α) and nitric oxide (NO). Since less attention has been paid to alkaloids in the diets than to polyphenols in this regard, we aimed at investigating anti-inflammatory activity of herb-derived alkaloids through suppression of TNF-α and NO production in lipopolysaccharide (LPS)-stimulated mouse RAW264 and/or human THP-1 cells. A harmala alkaloid, harmine, an opium alkaloid, papaverine, and Lycoris alkaloids, lycorine and lycoricidinol, showed TNF-α suppressive activities stronger than or comparable to that of a reference polyphenol, butein, in RAW264 cells (IC50=4, 10, 2.1, 0.02, and 8 μM, respectively). Other alkaloids showed no or marginal to moderate inhibitory activities. Similar tendency of inhibition was found for NO production in RAW264 cells and TNF-α production in THP-1 cells. In addition, harmine was found to suppress interleukin-6 (IL-6) production in RAW264 cells. The above four inhibitory alkaloids had essentially no antioxidative property in the superoxide anion scavenging assay. Western blotting and reverse transcriptase-polymerase chain reaction (RT-PCR) showed that harmine caused neither prevention of nuclear factor-κB (NF-κB) translocation into the nucleus nor inhibition of p38 mitogen activated protein kinase (MAPK) and c-Jun N-terminal kinase (JNK) phosphorylation, while that the LPS-induced transcription of TNF-α and inducible NO synthase was dose-dependently attenuated by harmine. This result suggests that the molecular mechanism of harmine action is different from those of many other anti-inflammatory phytochemicals. In conclusion, some herbal alkaloids like harmine, in spite of lacking antioxidative property, have potential as anti-inflammatory agents that strongly suppress TNF-α and NO production by a unique mechanism.View full abstractDownload PDF (752K) -
Masateru Ono, Keisuke Eguchi, Masatarou Konoshita, Chisato Furusawa, J ...Article type: Note
2011 Volume 59 Issue 3 Pages 392-396
Published: March 01, 2011
Released on J-STAGE: March 01, 2011
JOURNAL FREE ACCESSA new labdane-type diterpenoid glucoside and two new labdane-type diterpenoids were isolated from the fruit (chasteberry) of Vitex agnus-castus L. (Verbenaceae) along with 14 known compounds comprising seven labdane-type diterpenoids, one halimane-type diterpenoid, two oleanane-type triterpenoids, two ursane-type triterpenoids, one aromadendrane-type sesquiterpenoid, and one flavonoid. Their structures were characterized on the basis of spectroscopic data as well as chemical evidence. Furthermore, the antioxidative activities of the flavonoid were evaluated using five different analyses.View full abstractDownload PDF (704K) -
Rene Angelo Sarmiento Macahig, Katsuyoshi Matsunami, Hideaki OtsukaArticle type: Note
2011 Volume 59 Issue 3 Pages 397-401
Published: March 01, 2011
Released on J-STAGE: March 01, 2011
JOURNAL FREE ACCESSThe leaves of the endemic Philippine plant, Dillenia philippinensis yielded 11 compounds including one new sulfated glucoside and a new seco-A-ring oleanane-type triterpenoid. The molecular structures of these compounds were elucidated by means of NMR, MS and other spectroscopic techniques, as well as by comparison with literature data. Anti-Leishmania activity and cytotoxic activity against A549 human lung adenocarcinoma cells were also examined.View full abstractDownload PDF (574K) -
Xiao-Qing Lv, Jian-Guang Luo, Xiao-Bing Wang, Jun-Song Wang, Jun Luo, ...Article type: Note
2011 Volume 59 Issue 3 Pages 402-406
Published: March 01, 2011
Released on J-STAGE: March 01, 2011
JOURNAL FREE ACCESSTwo new norsesquiterpenoids, oxyphyllenotriol A (1) and oxyphyllone G (2), and two new sesquiterpenoids, oxyphyllol D (3) and oxyphyllol E (4), together with two known compounds (5, 6) were isolated from the fruits of Alpinia oxyphylla. Their structures were determined on the basis of spectroscopic analysis, including high resolution electrospray ionization mass spectrometry (HR-ESI-MS), 1D- and 2D-NMR, and the absolute configurations of 2 and 4 were determined by theoretical calculation of electronic circular dichroism (ECD) and comparison with the experimental ECD spectra.View full abstractDownload PDF (984K) -
Chin Piow Wong, Misae Shimada, Yuta Nagakura, Alfarius Eko Nugroho, Yu ...Article type: Note
2011 Volume 59 Issue 3 Pages 407-411
Published: March 01, 2011
Released on J-STAGE: March 01, 2011
JOURNAL FREE ACCESSFive new limonoids, ceramicines E—I (1—5), have been isolated from the bark of Chisocheton ceramicus. The structures and relative stereochemistry of them were fully elucidated based on 1D- and 2D-NMR data. Ceramicines E—I (1—5) exhibited moderate cell growth inhibitory activities on a range of cell lines (HL-60, A549, MCF7, and HCT116). The absolute structure of previously isolated ceramicine B (6) was also elucidated by circular dichroism (CD) and X-ray analysis.View full abstractDownload PDF (859K) -
Teisuke Harada, Tetsuhiro Nemoto, Long Jin, Yasumasa HamadaArticle type: Note
2011 Volume 59 Issue 3 Pages 412-415
Published: March 01, 2011
Released on J-STAGE: March 01, 2011
JOURNAL FREE ACCESSWe developed a novel (S)-L-phenylalanine derived-bidentate chiral diaminophosphine oxide (DIAPHOX) preligand (S,SP)-9b, which was successfully applied to Pd-catalyzed asymmetric allylic alkylation and amination. Using the Pd-(S,SP)-9b catalyst system, asymmetric allylic alkylation and amination proceeded very smoothly, affording the corresponding products in excellent yield with high enantiomeric excess. It is noteworthy that both enantiomers were accessible with high enantiomeric purity using the structurally related DIAPHOX preligands (S,SP)-9b and a monodentate chiral diaminophosphine oxide preligand (S,RP)-10a, both of which can be prepared from a single chiral source, (S)-L-phenylalanine.View full abstractDownload PDF (664K)
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