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Volume 55, Issue 3
Displaying 1-34 of 34 articles from this issue
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Review
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Masakazu Tanaka2007 Volume 55 Issue 3 Pages 349-358
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSα,α-Disubstituted amino acids are α-amino acids in which the hydrogen atom at the α-position of the L-α-amino acid is replaced with an alkyl substituent. The introduction of an α-alkyl substituent changes the properties of amino acids, with the conformational freedom of the side chain in the amino acids and the secondary structure of their peptides being especially restricted. The author developed a synthetic route of optically active α-ethylated α,α-disubstituted amino acids using chiral cyclic 1,2-diol as a chiral auxiliary. It was found that the preferred secondary structure of peptides composed of chiral α-ethylated α,α-disubstituted amino acids is a fully extended C5-conformation, whereas that of peptides composed of chiral α-methylated α,α-disubstituted amino acids is a 310-helical structure. Also, a new chiral cyclic amino acid; (3S,4S)-1-amino-3,4-di(methoxy)cyclopentanecarboxylic acid {(S,S)-Ac5cdOM}, and a bicyclic amino acid; (1R,6R)-8-aminobicyclo[4.3.0]non-3-ene-8-carboxylic acid {(R,R)-Ab5,6=c}, in which the α-carbon atom is not the chiral center but chiral centers exist at the side-chain cycloalkane skeleton, were designed and synthesized. The (S,S)-Ac5cdOM hexa- and octapeptides preferentially formed left-handed (M) helices, in which the helical-screw direction is exclusively controlled by the side-chain chiral centers. Contrary to the left-handed helices of (S,S)-Ac5cdOM peptides, the (R,R)-Ab5,6=c hexapeptide formed both diastereomeric right-handed (P) and left-handed (M) helices, and the twelve chiral centers at the side chain showed no preference for helical-screw direction. Thus, the chiral environment at the side chain is important for the control of helical-screw direction. Furthermore, the author designed a new class of chiral cyclic α,α-disubstituted amino acids that have pendant chiral centers at the substituent of the δ-nitrogen atom. The synthetic route would provide various optically-active cyclic α,α-disubstituted amino acids bearing a pendant chiral moiety.View full abstractDownload PDF (1010K)
Regular Articles
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Arpansiree Wongmekiat, Yuichi Tozuka, Kunikazu Moribe, Toshio Oguchi, ...2007 Volume 55 Issue 3 Pages 359-363
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSThe aim of this study was to investigate the factors affecting the formation of pranlukast nanoparticle prepared by co-grinding with β-cyclodextrin (β-CD) and to elucidate the mechanism of nanoparticle formation. The effects of grinding time, moisture content and CD content on the nanoparticle formation were evaluated by means of UV quantitative determination and particle size analysis. High-resolution scanning electron microscopy (HRSEM) was employed to observe drug nanoparticles in the ground mixture. Nanoparticle recovery was higher than 95% for 2 : 1 molecular mixtures of β-CD : pranlukast which had been ground for 10 min with moisture levels between 10 and 15%. While that of the 1 : 2 ground mixture prepared at 8% moisture level was only 57%. Nanoparticle recovery from β-CD : pranlukast 2 : 1 mixture ground for 1 min was 2.5%, while that of the 10 min ground mixture was as high as 95%. HRSEM demonstrated that primary drug nanoparticles having a particle size around 50 nm were observed in the ground mixture. The grinding time, the moisture content, and the CD content had significant influences on the formation of drug nanoparticles. The CD matrix may form and stabilize primary particles by its interaction with the particle surface through water molecules. Primary nanoparticles existed in the ground mixture as 50 nm drug nanocrystallites.View full abstractDownload PDF (789K) -
Khalifa Abulghasem El-Aroud, Adel Mohamed Abushoffa, Hisham Ezzat Abde ...2007 Volume 55 Issue 3 Pages 364-367
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSTwo simple and sensitive spectrophotometric and fluorimetric methods for the determination of tranexamic acid in tablets are developed. The methods are based on condensation the primary amino group of tranexamic acid with acetyl acetone and formaldehyde producing a yellow coloured product, which is measured spectrophotometrically at 335 nm or fluorimetrically at 480 nm the colour was stable for at least 1 h. Beer's law was valid within a concentration rang of 0.05—2.0 μg ml−1 spectrophotometrically and 0.05—0.25 μg ml−1 fluorimetrically. All the variables were studied to optimize the reaction conditions. No interference was observed in the presence of common pharmaceutical excipints. The validity of both methods was tested by analyzing tranexamic acid in its pharmaceutical preparations. Good recoveries were obtained and the results were comparable with those obtained by standard method.View full abstractDownload PDF (100K) -
Mohammad Abu Hena Mostofa Kamal, Nahoko Iimura, Tomohiro Nabekura, Shu ...2007 Volume 55 Issue 3 Pages 368-371
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSEnhancement of skin permeability of anionic diclofenac from non-aqueous vehicle isopropyl myristate (IPM) by ion-pair formation with either alkylamines or benzylamine as model cationic ions was examined in guinea pig dorsal skin. Diclofenac ion flux increased in the presence of these amines due to an increase in solubility. Maximum flux was observed in the presence of n-hexylamine, which induced 7.3-fold increase accompanied by a 45-fold increase in solubility. Permeability coefficients of the ionic form of diclofenac in the presence of benzylamine, n-hexylamine and iso-octylamine as counter ions in IPM were larger than those of the non-ionic form of diclofenac. Since the solubility of diclofenac was still limited, to obtain further enhancement of skin permeation, the effects of microemulsions as a vehicle consisting of phosphate buffered saline (PBS), isopropyl myristate (IPM), polyoxyethylene sorbitan monooleate (Tween 80) and ethanol were examined for transport of diclofenac-benzylamine ion-pairs. All microemulsion formulations tested increased diclofenac flux 4.9-fold to 10.7-fold over the value without a microemulsion accompanied by a 217-fold to 302-fold improvement in the solubility of diclofenac-benzylamine ion-pairs, but permeability coefficients were decreased 28—44 fold. Maximum enhancement was observed for a microemulsion with a ratio of PBS, IPM, ethanol and Tween 80 of 25 : 8 : 47 : 20 (w/w). The present findings suggest the usefulness of combined use of ion-pairs with microemulsions for enhancement of skin permeation of ionic drugs.View full abstractDownload PDF (74K) -
Carmen Balo, Carmen López, José Manuel Brea, Franco Fern ...2007 Volume 55 Issue 3 Pages 372-375
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSA series of [1,2,4]triazolo[1,5-c]quinazolines were prepared in satisfactory yields by reaction of some derivatives of 2-aminobenzohydrazide with several hydrochlorides of aromatic amidines, and their binding affinities for the recombinant human adenosine A2A and A2B receptors were determined. None of the new compounds showed noteworthy affinity for these receptors, though a very high affinity for the A2A receptor and, consequently, a high level of A2A/A2B selectivity was revealed for one of the synthesized compounds.View full abstractDownload PDF (100K) -
Yupei Shan, Xiaobing Wang, Xiang Zhou, Lingyi Kong, Masatake Niwa2007 Volume 55 Issue 3 Pages 376-381
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSTwo new labdane diterpene glycosides, forskoditerpenosides A, B (1, 2) and a new eudesmane sesquiterpene, 4β,7β,11-enantioeudesmantriol (3), were isolated from the ethanol extract of the whole plant of Coleus forskohlii. Their structures and stereochemistry were elucidated by extensive spectroscopic analysis and chemical methods. The structure of compound 3 was confirmed by X-ray diffraction. This is the first report about the occurrence of glycosides derived from the kind of labdane diterpene, 8,13-epoxy-labd-14-en-11-one, in the nature. Compounds 1 and 2 showed relaxative effects on isolated guinea pig tracheal spirals in vitro.View full abstractDownload PDF (189K) -
Lean-Teik Ng, Chun-Ching Lin, Chai-Ming Lu2007 Volume 55 Issue 3 Pages 382-384
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSIn the search for potential antioxidants, the naphthalenic compounds, 6-methoxysorigenin (2) and its glycosides [i.e. 6-methoxysorigenin-8-O-glucoside (3), α-sorinin (4), and 6-methoxysorigenin-8-rutinoside (5)] isolated from Rhamnus nakaharai together with two acylates (peracetate and perpropionate) of 2 were evaluated for antioxidant activities using 2,2-diphenyl-1-picrylhydrazyl (DPPH), metal chelating, and electron spin resonance (ESR) assays as well as anti-lipid peroxidation assay. The results showed that 2 possesses the most potent DPPH radical scavenging, metal chelating, and anti-lipid peroxidation activities with IC50 values of 3.48, 615.90, and 5.95 μg/ml, respectively. The glycosides 3, 4, and 5 showed decreasing antioxidant activity that was related to an increased substitution at 1,8-dihydroxyl with sugar molecules. This suggests the importance of 1,8-dihydroxyl of 2 in the antioxidative effect. The iron chelation result could further explain the main cause of increasing antioxidant activity in 2. The acylates of 2 (2a peracetate and 2b perpropionate), although lacking a free hydroxyl, also exhibited significant anti-lipid peroxidation effect. ESR results further demonstrated that 2 possesses strong antioxidant activities. Taken together, this study shows that 2 is a potent antioxidant and may also be used for designing new iron chelators for clinical applications.View full abstractDownload PDF (75K) -
Samia Ammar, Mohamed Ali Mahjoub, Nesrine Charfi, Ines Skandarani, Lei ...2007 Volume 55 Issue 3 Pages 385-388
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSA new skeleton of an O-heteroside natural substance named zinolol, the first representative of a new class of aminated hydroxyhydroquinone, has been isolated from the whole plant Anagallis monelli. Its structure has been established by one and two dimensional NMR spectroscopic procedures. Antioxidant, mutagenic, antimutagenic activities were realised and positive results were recorded.View full abstractDownload PDF (69K) -
Shin-ichi Kondo, Hisato Mori, Yasushi Sasai, Masayuki Kuzuya2007 Volume 55 Issue 3 Pages 389-392
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSThe first example is presented here of an amiphiphilic block copolymer synthesized by mechanochemical solid-state polymerization and used to form polymeric micelles. A model amphiphilic block copolymer was synthesized first, possessing galactose as a hydrophilic side chain and theophylline as a hydrophobic side chain, by mechanochemical solid-state polymerization. The resulting copolymer had a narrow molecular weight distribution. Polymeric micelle formation was subsequently carried out with the copolymer by a dialysis method. To gain insight into the physicochemical properties of the polymeric micelle, dynamic light scattering (DLS) measurements were performed. A narrow distribution of diameters was observed in the polymeric micelle solution, and these micelles were disrupted by the addition of sodium dodecyl sulfate (SDS). It was also confirmed by DLS measurements that the polymeric micelles were spherical. These results suggested that the block copolymer synthesized by mechanochemical solid-state polymerization was as suitable for the preparation of polymeric micelles as materials obtained by living polymerization.View full abstractDownload PDF (107K) -
Tetsuji Noguchi, Naoki Tanaka, Toyoki Nishimata, Riki Goto, Miho Hayak ...2007 Volume 55 Issue 3 Pages 393-402
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSFactor Xa (FXa) is well known to play a pivotal role in blood coagulation, so FXa inhibitor is a promising drug candidate for prophylaxis and treatment of thromboembolic diseases. In the course of our research, we have found that (R)-5-[1-(acetimidoyl)piperidin-4-yloxy]-2-(7-amidinonaphthalen-2-yl)-1-(ethanesulfonyl)indoline ((R)-1) showed potent FXa inhibitory activity in vitro. However, single oral administation (RS)-1 showed high toxicity in mice. Among newly synthesized compounds, ({(RS)-5-[1-(acetimidoyl)piperidin-4-yloxy]-2-(7-amidinonaphthalen-2-yl)indolin-1-yl}sulfonyl)acetic acid ((RS)-11d) showed more potent FXa inhibitory activity and higher safety than (RS)-1. The R-isoform of compound 11d ((R)-11d) exhibited potent in vitro anticoagulant activity in human and hamster plasma. Orally administered (R)-11d also showed dose-dependent potent anticoagulant activity in hamsters, marmosets and cynomolgus monkeys. Compound (R)-11d with potent anticoagulant activity and high safety is therefore favorable as a novel oral FXa inhibitor.View full abstractDownload PDF (322K) -
Toshinobu Seki, Katsunori Shinohara, Naoko Kato, Masaki Uchida, Hidesh ...2007 Volume 55 Issue 3 Pages 403-406
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSPolypropyleneglycol (PPG) was used as a dispersion medium for the preparation of microspheres (MS) consisting of starch, gelatin, whey protein or dextran. Aqueous solutions of the polymers were dispersed in PPG at various initial temperatures and then the systems were cooled to 0.5 °C to allow water in the dispersed phase to dissolve in PPG. The particle size of the starch-MS was dependent on the initial temperature of PPG in the preparation process. There were two different processes for particle generation in the procedure. One of them was via the formation of a temporary emulsion during the early phase of dispersion of the aqueous polymer solution into PPG. The other was via the stable emulsion in which the aqueous polymer solution was dispersed in water-saturated PPG. The particle size generated in the former process was dependent on the initial temperature: a high temperature gave large particles but a low temperature gave small particles, while that in the latter process was temperature-independent. This preparation method for MS will be useful for the formulation of heat-sensitive material, such as protein-containing drugs.View full abstractDownload PDF (1576K) -
Takashi Kojima, Fumie Kato, Reiko Teraoka, Yoshihisa Matsuda, Shuji Ki ...2007 Volume 55 Issue 3 Pages 407-411
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSTwo novel pseudopolymorphs, methanolate and ethanolate of tamoxifen [(Z)-2-[4-(1,2-diphenyl-1-butenyl)phenoxy]-N,N-dimethylethylamine]citrate, were prepared in addition to forms A and B reported previously. Their crystalline forms were identified and characterized by powder and single crystal X-ray diffractometry, differential scanning calorimetry, thermogravimetric analysis, hot-stage microscopy, scanning electron microscopy and diffuse reflectance infrared Fourier-transform spectroscopy, and their physicochemical stability was also evaluated. The results of single crystal X-ray analysis and thermogravimetric analysis of methanolate and ethanolate suggested that the stoichiometry of tamoxifen citrate : methanol and tamoxifen citrate : ethanol could be composed of a 1 : 1 molecular ratio for both solvates. The results of physicochemical stability evaluations at 75 and 97% RH at 40 and 60 °C indicated that the metastable form A was quite stable for at least 2 months even under severe storage conditions, whereas methanolate immediately transformed to a crystalline mixture of forms A and B, and subsequently changed to the stable form B.View full abstractDownload PDF (847K) -
Annett Mikolasch, Timo Horst Johannes Niedermeyer, Michael Lalk, Sabin ...2007 Volume 55 Issue 3 Pages 412-416
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSSixteen novel cephalosporins were synthesized by amination of 2,5-dihydroxybenzoic acid derivatives with the aminocephalosporins cefadroxil, cefalexin, cefaclor, and the structurally related carbacephem loracarbef using laccases from Trametes sp. or Myceliophthora thermophila. All products inhibited the growth of several Gram positive bacterial strains in the agar diffusion assay, among them methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci. The products protected mice against an infection with Staphylococcus aureus lethal to the control animals. Cytotoxicity and acute toxicity of the new compounds were negligible. The results show the usefulness of laccase for the synthesis of potential new antibiotics. The biological activity of the new compounds stimulates intensified pharmacological tests.View full abstractDownload PDF (99K) -
Ryosuke Saijo, Hiroyuki Murakami, Saori Tsunekawa, Souhei Imanishi, Na ...2007 Volume 55 Issue 3 Pages 417-421
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSAs an interesting type of molecular recognition at a membrane surface, the tri-O-acetic acid ester (host 2) of hexahomotrioxacalix[3]arene, when incorporated into poly(vinyl chloride) (PVC) liquid membranes, displays a high potentiometric selectivity for dopamine over, not only other catecholamines (noradrenaline, adrenaline), but also quaternary ammonium guests (tetramethylammonium, choline, and acetylcholine) and inorganic cations (Na+, K+, NH4+). Interestingly, changes in membrane potential based on the host–guest complexation of host 2 that were observed dopamine/inorganic cation selectivity were not displayed by the related hosts 3 and 4, which contain amide substituents. This paper describes our efforts to separately estimate the two factors contributing to the dopamine selectivities, i.e., the guest lipophilicity factor and the host–guest complexation factor, in an attempt to understand the effects of the O-substituents of these hosts. The potentiometric experiments showed that, although the guests had roughly equal lipophilicity, the electromotive force (EMF) response for dopamine by host 2 was excellent. Furthermore, host 2 displayed ca. a 20-fold stronger complexation for dopamine, compared to noradrenaline, adrenaline, K+, and NH4+ cations. These results indicate that the high potentiometric selectivity of the ion-selective electrode for dopamine mainly reflect, not the guest lipophilicity factor but the host–guest complexation factor. On the other hand, host 3 displayed ca. a 3000-fold stronger binding to Na+ than dopamine, thus explaining the reasons for the lower dopamine-selectivities of host 3 compared to host 2. It is interesting to note that the high potentiometric selectivities for dopamine were displayed by not only host 2 but also host 5, regardless of the simple structure of the O-substituents.View full abstractDownload PDF (557K)
Notes
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Zu-Jian Wu, Ming-An Ouyang, Cong-Zhou Wang, Zheng-Kun Zhang2007 Volume 55 Issue 3 Pages 422-427
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSSix new triterpenoid saponins of the ursane types were isolated from the MeOH extract of the leaves of Ilex oblonga. They were oblonganoside A (1), oblonganoside B (2), oblonganoside C (6), oblonganoside D (8), oblonganoside E (9), and oblonganoside F (10), together with three known triterpenoid saponins. The structures of these compounds were elucidated on the basis of spectroscopic analysis, and compound 1 showed appreciable inhibitory activity against TMV replication with EC50 value 0.074 mM.View full abstractDownload PDF (121K) -
Masayuki Yoshikawa, Toshio Morikawa, Hisanori Kobayashi, Akihiko Nakam ...2007 Volume 55 Issue 3 Pages 428-434
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSThe methanolic extract from the fruit of Citrullus colocynthis showed an inhibitory effect on ear passive cutaneous anaphylaxis reactions as a type I allergic model in mice. From the methanolic extract, two new cucurbitane-type triterpene glycosides, colocynthosides A and B, were isolated together with 17 known constituents. The structures of colocynthosides A and B were elucidated on the basis of chemical and physicochemical evidence. In addition, the principal cucurbitane-type triterpene glycoside, cucurbitacin E 2-O-β-D-glucopyranoside, and its aglycon, cucurbitacin E, exhibited the antiallergic activity at a dose of 100 and 1.25 mg/kg, p.o., respectively.View full abstractDownload PDF (231K) -
Toshio Morikawa, Yi Zhang, Seikou Nakamura, Hisashi Matsuda, Osamu Mur ...2007 Volume 55 Issue 3 Pages 435-441
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSSix new megastigmane glycosides, sedumosides E1, E2, E3, F1, F2, and G, were isolated from the whole plant of Sedum sarmentosum (Crassulaceae). The structures of new constituents including the absolute configuration were elucidated on the basis of chemical and physicochemical evidence.View full abstractDownload PDF (308K) -
Chibuike C. Udenigwe, Athar Ata, Radhika Samarasekera2007 Volume 55 Issue 3 Pages 442-445
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSGlutathione S-transferase inhibition assay-guided fractionations on the ethanolic extract of the bark of Caesalpinia bonduc resulted in the isolation of a new sterol, 17-hydroxy-campesta-4,6-dien-3-one (1) along with four known compounds, 13,14-seco-stigmasta-5,14-dien-3α-ol (2), 13,14-seco-stigmasta-9(11),14-dien-3α-ol (3), caesaldekarin J (4) and pipataline (5) as active constituents. Structures of compounds 1—5 were established on the basis of extensive NMR spectroscopic studies. The compounds (1—5) were isolated on the basis of their inhibitory activity against glutathione S-transferase, an enzyme that has been implicated in resistances during treatment of cancer and parasitic infections. Efforts to study structure–activity relationships of compounds 2 and 3 were also made by modifying their structures. The IC50 values of these compounds and their derivatives ranged from 57—380 μM and were compared to the inhibitory effects due to sodium taurocholate, an isoprene-derived GST inhibitor (IC50=398 μM). A plausible biosynthesis of 13,14-seco-steroids has also been proposed.View full abstractDownload PDF (115K) -
Ahmad Toufic Kabbani, Hassan Hasan Hammud, Amer Mohammed Ghannoum2007 Volume 55 Issue 3 Pages 446-450
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSCopper and cobalt complexes with 4-chloro-3-nitrobenzoate (ClNBz) and the nitrogen ligands 1,3-diaminopropane (1,3-DAP) or o-phenylenediamine (o-PDA), were prepared and characterized. The complexes [Cu(ClNBz)2(1,3-DAP)] (1), [Cu(ClNBz)(o-PDA)]Cl (2), [Co(ClNBz)2(1,3-DAP)] (3) and [Co(ClNBz)2(o-PDA)2] (4) were characterized by FTIR, UV–Visible absorption, elemental analysis and thermal analysis. Complex [Cu(ClNBz)(o-PDA)]Cl (2) shows high antibacterial activity as indicated by its ability to inhibit the growth of Staphylococcus aureus, Enterococcus faecalis.View full abstractDownload PDF (453K) -
Hui Zhang, Ning Kang, Feng Qiu, Ge-Xia Qu, Xin-Sheng Yao2007 Volume 55 Issue 3 Pages 451-454
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSFurther study on the microbial transformation of curcumol (1) by Cunninghamella blakesleana (AS3.970) led to the isolation of four novel metabolites. Their structures were elucidated as 3β-hydroxy curcumol (2), 12-hydroxy curcumol (3), 1α-hydroxy-10β,14-epoxy curcumol (4) and (2S,4S,5S,7S)-10-hydroxymethyl-7-isopropyl-2-methoxy-4-methyl-1-oxaspiro[4,6]undec-10-en-8-one (5) on the basis of spectral methods. All of them were characterized as new compounds.View full abstractDownload PDF (89K) -
Wenkui Li, Xudong Xu, Hongjie Zhang, Cuiying Ma, Harry Fong, Richard v ...2007 Volume 55 Issue 3 Pages 455-458
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSTwo new flavonoid glycosides, 5-hydroxy-7,8-dimethoxy (2R)-flavanone-5-O-β-D-glucopyranoside (1) and 5-hydroxy-7,8,2′,5′-tetramethoxy-flavone-5-O-β-D-glucopyranoside (2), and a new diterpenoid, andrographic acid (3), along with andrographidine A (4) were isolated from Andrographis paniculata, and their structures were determined on the basis of physicochemical and spectroscopic analysis. Compound 3 was evaluated for cytotoxicity to KB cells along with andrographolide, isoandrographolide, neoandrographolide and 14-deoxy-11,12-didehydroandrographolide obtained from A. paniculata in the present study. Cytotoxicity was observed for andrographolide and isoandrographolide with ED50 values of 6.5 and 5.1 μg/ml, respectively.View full abstractDownload PDF (98K) -
Jinsoo Lee, Weihong Wang, Jongki Hong, Chong-Ok Lee, Sook Shin, Kwang ...2007 Volume 55 Issue 3 Pages 459-461
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSA new butenolide (1) was isolated, along with a known acyclic polyhalogenated monoterpene (2), from the brittle star Ophiomastix mixta. The structures were defined by analysis and comparision of the spectral data with those in the literature. The 2,3-dimethyl butenolide (1) is uncommon and first encountered in a marine organism. The compounds were tested for cytotoxicity against a panel of five human solid tumor cell lines and displayed mild to significant activity.View full abstractDownload PDF (96K) -
Masafumi Kaneko, Koji Yamada, Tomofumi Miyamoto, Masanori Inagaki, Ryu ...2007 Volume 55 Issue 3 Pages 462-463
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSThe effects of the gangliosides isolated from echinoderms on the neuritogenesis of a rat pheochromocytoma cell line (PC-12 cells) in the presence of nerve growth factor were investigated. The results show that they displayed neuritogenic activity. Based on the observed results, a structure–activity relationship has been established.View full abstractDownload PDF (127K) -
Bruno Ndjakou Lenta, Silvère Ngouela, Fabrice Fekam Boyom, Ferd ...2007 Volume 55 Issue 3 Pages 464-467
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSBazouanthrone (1), a new anthrone derivative, has been isolated from the root bark of Harungana madagascariensis, together with known compounds, feruginin A (2), harunganin (3), harunganol A (4), harunganol B (5), friedelan-3-one (6) and betulinic acid (7). The structure of the compound (1) was assigned as 3,5,8,9-tetrahydroxy-2,4,4-tri-(3,3-dimethylallyl)-6-methyl-1-(4H)-anthracenone, by means of spectroscopic analysis. The anti-plasmodial activity of the isolated compounds was evaluated in culture against W2 strain of Plasmodium falciparum. All the compounds were found to be active against the Plasmodium parasites with bazouanthrone (1) showing particular potency (IC50=1.80 μM).View full abstractDownload PDF (91K) -
Guita Nicolaewsky Jubilut, Eduardo Maffud Cilli, Edson Crusca, Jr., El ...2007 Volume 55 Issue 3 Pages 468-470
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSBased on our studies of the stability of model peptide-resin linkage in acid media, we previously proposed a rule for resin selection and a final cleavage protocol applicable to the Nα-tert-butyloxycarbonyl (Boc)-peptide synthesis strategy. We found that incorrect choices resulted in decreases in the final synthesis yield, which is highly dependent on the peptide sequence, of as high as 30%. The present paper continues along this line of research but examines the Nα-9-fluorenylmethyloxycarbonyl (Fmoc)-synthesis strategy. The vasoactive peptide angiotensin II (AII, DRVYIHPF) and its [Gly8]-AII analogue were selected as model peptide resins. Variations in parameters such as the type of spacer group (linker) between the peptide backbone and the resin, as well as in the final acid cleavage protocol, were evaluated. The same methodology employed for the Boc strategy was used in order to establish rules for selection of the most appropriate linker-resin conjugate or of the peptide cleavage method, depending on the sequence to be assembled. The results obtained after treatment with four cleavage solutions and with four types of linker groups indicate that, irrespective of the circumstance, it is not possible to achieve complete removal of the peptide chains from the resin. Moreover, the Phe-attaching peptide at the C-terminal yielded far less cleavage (50—60%) than that observed with the Gly-bearing sequences at the same position (70—90%). Lastly, the fastest cleavage occurred with reagent K acid treatment and when the peptide was attached to the Wang resin.View full abstractDownload PDF (68K) -
Umar Farooq, Afsar Khan, Viqar Uddin Ahmad, Saleha Suleman Khan, Farza ...2007 Volume 55 Issue 3 Pages 471-473
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSTwo new tetracyclic diterpenoids trivially named as limbatenolide D (1) and limbatenolide E (2) have been isolated from Otostegia limbata. The structure elucidation of the compounds was based primarily on two-dimensional (2D) NMR techniques and on comparison with the literature data.View full abstractDownload PDF (88K) -
Jia-Ming Sun, Jun-Shan Yang, Hui Zhang2007 Volume 55 Issue 3 Pages 474-476
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSTwo new flavanone glucosides, (2S)-5,7,3′,5′-tetrahydroxy-flavanone 7-O-β-D-allopyranoside (1) and (2S)-5,7,3′,5′-tetrahydroxy-flavanone 7-O-β-D-glucopyranosie (2) were isolated from the stems and leaves of Jasminum lanceolarium, along with five known compounds: Betulinaldehyde (3), betulinic acid (4), betulin (5), syringin (6) and Liriodendrin (7). Their structures were determined on the basis of spectroscopic and chemical methods. The isolated compounds were screened for their in vitro antioxidant activity through DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging assay. Compounds 2 demonstrated significant radical scavenging activity.View full abstractDownload PDF (76K) -
Jong-Woong Ahn, Kyoung Hwa Jang, Hyeong-Cheol Yang, Ki-Bong Oh, Hyi-Se ...2007 Volume 55 Issue 3 Pages 477-479
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSTwo new bithiazole metabolites (3, 4) along with the previously reported compounds (1, 2) were isolated from the culture broth of the gliding bacterium Myxococcus fulvus collected from a Korean soil. The structures of these compounds were determined to be analogous to myxothiazole A on the basis of combined spectroscopic analyses. The new compounds exhibited significant cytotoxicity and moderate antifungal activity against the mouse fibloblast cell-line L929 and Candida albicans, respectively. These data were consistent with the previous finding that the bioactivity of myxothiazoles was highly dependent on the presence of terminal methoxy enol functionality.View full abstractDownload PDF (69K) -
Hongfei Liu, Tianhui Sun, Feiqian Yu, Xin Zhao, Hong Guo, Weisan Pan2007 Volume 55 Issue 3 Pages 480-481
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSWe previously reported the preparation of the salbutamol sulfate pulsatile-release capsules with the pH-sensitive ion exchange resin as the carriers. In the present study, we investigated the pharmacokinetics of the salbutamol sulfate pulsatile-release capsules in beagle dogs. The analysis method was established for the drugs in vivo by HPLC method. The pharmacokinetics parameters of pulsatile-release salbutamol sulfate and reference tablet were AUC0—24 (ng·h/ml) 1031.8±123.1, 1112.6±118.24, Cmax (ng/ml) 172.4±21.4, 179.3±26.1, Tmax (h) 3.8±0.6, 1.5±0.5, Tlag (h) 2.7±0.5, 0.3±0.2. The results showed that the test dosage forms was bioequivalent with reference dosage form, and had an obviously pulsatile-release effect.View full abstractDownload PDF (57K) -
Younghwa Na2007 Volume 55 Issue 3 Pages 482-487
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSThe solvolysis rates for the substituted C(7)-cyclohexylamino- or C(8)-cyclohexyliminomitomycins 8-19 were determined in buffered methanolic solutions (0.06 M bis-Tris·HCl, pH: 5.5) at 25 °C and then compared with mitomycin C (1) and porfiromycin. Kinetic studies showed that C(8)-cyclohexyliminomitomycins 8-13 underwent solvolysis 150-230 times faster than mitomycin C (1) to give C(1)-methoxymitosene products. The solvolysis rates were slightly faster than that reported for 6. The C(7)-(2′-hydroxy)cyclohexylaminomitomycins 16-19 exhibited comparable solvolysis rates with 1 and porfiromycin.View full abstractDownload PDF (222K) -
Hitoshi Yoshimitsu, Makiko Nishida, Masafumi Okawa, Toshihiro Nohara2007 Volume 55 Issue 3 Pages 488-491
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSFour new triterpene glycosides, named nigellosides A, B, C, and D, were from the air-dried aerial parts of Nigella damascena L. (Ranunculaceae), and the structures were elucidated on the basis of spectroscopic data including 2D NMR spectra and chemical evidence. Their chemical structures have been characterized as 3-O-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl gypsogenin 28-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl ester, 3-O-β-D-glucopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl gypsogenin 28-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl ester, 3-O-α-L-rhamnopyranosyl-(1→2)-β-D-xylopyranosyl hederagenin 28-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl ester, and 3-O-β-D-glucopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-β-D-xylopyranosyl hederagenin 28-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl ester.View full abstractDownload PDF (84K) -
Hideyuki Ito, Masateru Miyake, Eisei Nishitani, Kyoko Miyashita, Morio ...2007 Volume 55 Issue 3 Pages 492-494
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSA new complex tannin, cowaniin (1) was isolated from the leaves and stems of Cowania mexicana (Rosaceae), and its structure was characterized as novel C-glucosidic tannin dimer linked through (+)-catechin on the basis of spectral and chemical evidence. The inhibitory effect on activation of the Epstein-Barr virus early antigen was assessed for cowaniin. Six known polyphenols and related compounds, including a nitrile glucoside, purshianin, were also characterized.View full abstractDownload PDF (135K) -
Akira Kanai, Yoshifumi Takeda, Kouji Kuramochi, Atsuo Nakazaki, Susumu ...2007 Volume 55 Issue 3 Pages 495-499
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSThe synthesis of the key intermediate (4) in the proposed route to D8646-2-6 is described. The aldol reaction of the carbohydrate-containing pyrone 7 with the aldehyde 6 was accomplished by using LiHMDS and Sc(OTf)3 or Sn(OTf)2. The stepwise dehydration reaction of the aldol adduct 14, followed by Stille coupling with vinyl stannane 5 which contained phosphonate gave the desired 4.View full abstractDownload PDF (188K)
Communications to the Editor
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Catalytic Activity of Silica Gels Bound Manganese(III)–Porphyrin on Oxidative Reaction of AdrenalineYouji Kitamura, Tsutomu Takatsuki, Mayu Kawamoto, Madoka Saito, Akimas ...2007 Volume 55 Issue 3 Pages 500-502
Published: 2007
Released on J-STAGE: March 01, 2007
JOURNAL FREE ACCESSTo develop a solid catalysis on oxidative reaction of adrenaline (Ad), supports bound metal-tetrakis(4-carboxyphenyl)porphine (M-TCPP) were investigated. Silica gels bound Mn-TCPP were proved to has a superior activity in the oxidation of Ad and be able to serve as a useful oxidase model for Ad.View full abstractDownload PDF (109K)
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