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p. 904-916
Received: 1 November 2008; in revised form: 17 December 2008 / Accepted: 23 December 2008 / Published: 25 February 2009
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| Download PDF Full-text (283 KB) Abstract: Complex formation of the glutathione peroxidase mimics 2,2¢-ditelluro-bridged b-cyclodextrin (1) and 2,2¢-diseleno-bridged b-cyclodextrin (2), with S -substituted dinitrophenyl glutathione (3) were determined by ultraviolet-visible (UV-Vis) absorption spectroscopy in phosphate buffer (pH 7.4) and 1 H-NMR spectroscopy. Molecular mechanics (MM2) modeling calculations were used to deduce a three-dimensional model for each complex. The dinitrophenyl (DNP) group of 3 appears to penetrate the cavity of b-cyclodextrin (b-CD) or 1, but it is located between the two secondary rims of 2. The complexes’ stability constants (K s ) from 19 to 37 °C, Gibbs free energy changes (DG° ), DH° and TDS° for 1:1 complexes of b-CD, 1 and 2 with ligand 3 as obtained from UV-Vis spectra were compared. The binding of 3 by the three cyclodextrin hosts generally decreased in the order of 1>2>b-CD. The binding ability of 3 by b-CD, 1 and 2 was discussed with regard to the size/shape-fit concept, the induced-fit interaction, and the cooperative interaction of the dual hydrophobic cavities. The binding ability of 1>2indicated that the length of linkage between two cyclodextrin units plays a crucial role in the interaction with 3.
p. 917-924
Received: 2 February 2009; in revised form: 17 February 2009 / Accepted: 26 February 2009 / Published: 26 February 2009
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| Download PDF Full-text (145 KB) Abstract: Treatment of 1-(2-bromoarylmethyl)-3,4-dihydroisoquinolines with oxalyl chloride and triethylamine gave 1-(2-bromophenyl)-5,6-dihydropyrrolo[2,1-a]isoquinoline-2,3-dione derivatives, for example, 1-(2-bromophenyl)-5,6-dihydro-8,9-dimethoxypyrrolo[2,1-a]isoquinoline-2,3-dione. Radical cyclisation of these derivatives with tributyltin hydride and 1,1-azobis(cyclohexanecarbonitrile) afforded telisatin A, telisatin B and lettowianthine.
p. 925-938
Received: 4 February 2009; in revised form: 23 February 2009 / Accepted: 26 February 2009 / Published: 27 February 2009
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| Download PDF Full-text (353 KB) Abstract: The purpose of this study was to compare the essential oil profiles of four South-Croatian Satureja species, as determined by GC/FID and GC/MS, with their DNA sequences for an internal transcribed spacer (ITS1-5.8S-ITS2) of the nuclear ribosomal DNA. A phylogenetic analysis showed that S. montana and S. cuneifolia, characterized by a similar essential oil composition, rich in the monoterpene hydrocarbon carvacrol, clustered together with high and moderate bootstrap support. On the contrary, S. subspicata and S. visianii, characterized by quite unique essential oil compositions, clustered together with the moderate bootstrap support. All four Croatian Satureja species clustered in one clade, separately from Macaronesian S. hortensis ,although it had essential oil composition similar to that of S. montana and S. cuneifolia. This is the first report on the comparison between the phytochemical and DNA sequence data in Satureja species and useful contribution to the better understanding of interspecies relationships in this genus.
p. 939-952
Received: 15 January 2009; in revised form: 11 February 2009 / Accepted: 12 February 2009 / Published: 27 February 2009
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| Download PDF Full-text (202 KB) Abstract: We report the isolation of several coumarins and the stereochemical assessment of some pyranocoumarins, as well as the antibacterial and antioxidant activities of the three most abundant ones (grandivittin, agasyllin and aegelinol benzoate) isolated from the roots of Ferulago campestris collected in Sicily and of the hydrolysis product (aegelinol). Aegelinol and agasyllin showed antibacterial activity against nine ATCC and the same clinically isolated Gram-positive and Gram-negative bacterial strains. At a concentration between 16 and 125 mg/mL both coumarins showed a significant antibacterial effect against both Gram-negative and Gram-positive bacteria. In particular the ATCC strains Staphylococcus aureus, Salmonella thypii, Enterobacter cloacae and Enterobacter earogenes (MIC = 16 and 32 mg/mL for aegelinol and agasyllin, respectively) were the most inhibited. Antibacterial activity was also found against Helicobacter pylori : a dose-dependent inhibition was shown between 5 and 25 mg/mL. The antioxidant activity of the coumarins was evaluated by their effects on human whole blood leukocytes (WB) and on isolated polymorphonucleate (PMN) chemiluminescence (CL), PMA-stimulated and resting.
p. 953-958
Received: 8 January 2009; in revised form: 17 February 2009 / Accepted: 17 February 2009 / Published: 27 February 2009
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| Download PDF Full-text (239 KB) Abstract: Two new neolignans, (7S ,8R )-guaiacylglycerol-8-O -4′-sinapyl ether 9′-O -β-D- glucopyranoside (1) and (7S ,8R )-syringylglycerol-8-O -4′-sinapyl ether 9′-O -β-D-gluco- pyranoside (2) were isolated from the leaves of Syringa velutina Kom.. Their structures were established by chemical properties and spectroscopic evidence.
p. 959-969
Received: 4 December 2008; in revised form: 7 February 2009 / Accepted: 17 February 2009 / Published: 2 March 2009
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| Download PDF Full-text (169 KB) Abstract: The effect of [10]-gingerol on cytosol free Ca2+ concentration ([Ca2+ ]i ) and viability is large unknown. This study examines the early signaling effects of [10]-gingerol on human colorectal cancer cells. It was found that this compound caused a slow and sustained rise of [Ca2+ ]i in a concentration-dependent manner. [10]-Gingerol also induced a [Ca2+ ]i rise when extracellular Ca2+ was removed, but the magnitude was reduced by 38%. In a Ca2+ -free medium, the [10]-gingerol-induced [Ca2+ ]i rise was partially abolished by depleting stored Ca2+ with thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor). The elevation of [10]-gingerol-caused [Ca2+ ]i in a Ca2+ -containing medium was not affected by modulation of protein kinase C activity. The [10]-gingerol-induced Ca2+ influx was insensitive to L-type Ca2+ channel blockers. At concentrations of 10-100 mM, [10]-gingerol killed cells in a concentration-dependent manner. These findings suggest that [10]-gingerol induces [Ca2+ ]i rise by causing Ca2+ release from the endoplasmic reticulum and Ca2+ influx from non-L-type Ca2+ channels in SW480 cancer cells.
p. 970-978
Received: 8 December 2008; in revised form: 13 January 2009 / Accepted: 15 January 2009 / Published: 3 March 2009
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| Download PDF Full-text (266 KB) Abstract: The antioxidant activity of fresh and dried plant extracts of Paederia foetida and Syzygium aqueum were studied using β-carotene bleaching and the 2,2’-azinobis(3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS) radical cation assay. The percentage of antioxidant activity for all extract samples using both assays was between 58 and 80%. The fresh samples of both plants had higher antioxidant activity than the dried samples. The results of the β-carotene bleaching assay were correlated (R2 = 0.9849) with those of the ABTS assay.
p. 979-1012
Received: 30 November 2008; in revised form: 7 January 2009 / Accepted: 6 February 2009 / Published: 3 March 2009
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| Download PDF Full-text (368 KB) Abstract: Peptic ulcers are a common disorder of the entire gastrointestinal tract that occurs mainly in the stomach and the proximal duodenum. This disease is multifactorial and its treatment faces great difficulties due to the limited effectiveness and severe side effects of the currently available drugs. The use of natural products for the prevention and treatment of different pathologies is continuously expanding throughout the world. This is particularly true with regards to flavonoids, which represent a highly diverse class of secondary metabolites with potentially beneficial human health effects that is widely distributed in the plant kingdom and currently consumed in large amounts in the diet. They display several pharmacological properties in the gastroprotective area, acting as anti-secretory, cytoprotective and antioxidant agents. Besides their action as gastroprotectives, flavonoids also act in healing of gastric ulcers and additionally these polyphenolic compounds can be new alternatives for suppression or modulation of peptic ulcers associated with H. pylori. In this review, we have summarized the literature on ninety-five flavonoids with varying degrees of antiulcerogenic activity, confirming that flavonoids have a therapeutic potential for the more effective treatment of peptic ulcers.
p. 1013-1031
Received: 21 January 2009; in revised form: 18 February 2009 / Accepted: 24 February 2009 / Published: 4 March 2009
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| Download PDF Full-text (270 KB) Abstract: Brominated anthraquinones can be synthesized directly from bromothiophenes when these are reacted with 1,4-naphthoquinones in the presence of meta-chloroperoxybenzoic acid. The bromoanthraquinones are versatile building blocks in the preparation of arylated anthraquinones and of extended π-systems with interspersed anthraquinone units.
p. 1032-1043
Received: 17 November 2008; in revised form: 6 January 2009 / Accepted: 24 February 2009 / Published: 4 March 2009
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| Download PDF Full-text (283 KB) Abstract: Antioxidant activities of the aqueous and ethanol extracts of pigeonpea [Cajanus cajan (L.) Millsp.] leaves, as well as petroleum ether, ethyl acetate, n -butanol and water fractions and the four main compounds separated from the ethanol extract, i.e. cajaninstilbene acid (3-hydroxy-4-prenylmethoxystilbene-2-carboxylic acid), pinostrobin, vitexin and orientin, were examined by a DPPH radical-scavenging assay and a β-carotene-linoleic acid test. In the DPPH system, the antioxidant activity of the ethanol extracts was superior to that of the aqueous extracts, with IC50 values were 242.01 and 404.91 µg/mL, respectively. Among the four fractions, the ethyl acetate one showed the highest scavenging activity, with an IC50 value of 194.98 µg/mL. Cajaninstilbene acid (302.12 µg/mL) and orientin (316.21 µg/mL) showed more efficient radical-scavenging abilities than pinostrobin and vitexin. In the β-carotene-linoleic acid test, the inhibition ratio (%) of the ethyl acetate fraction (94.13%±3.41%) was found to be the highest, being almost equal to the inhibition capacity of the positive control BHT (93.89%±1.45%) at 4 mg/mL. Pinostrobin (>500 µg/mL) and vitexin (>500 µg/mL) showed insignificant antioxidant activities compared with cajaninstilbene (321.53 µg/mL) and orientin (444.61 µg/mL). In general, the ethyl acetate fraction of the ethanol extract showed greater activity than the main compounds in both systems, such results might be attributed to the synergistic effects of the components. The antioxidant activities of all the tested samples were concentration-dependent. Based on the results obtained, we can conclude that the pigeonpea leaf extracts may be valuable natural antioxidant sources and are potentially applicable in both medicine and the healthy food industry.
p. 1044-1055
Received: 4 February 2009; in revised form: 26 February 2009 / Accepted: 2 March 2009 / Published: 5 March 2009
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| Download PDF Full-text (293 KB) Abstract: The immobilization of some coumarin derivatives on modified poly(ethylene glycol)s is reported and the influence of the polymeric support on the photoluminescence activity of the compounds is discussed. Upon ultraviolet excitation, the derivatives showed coumarin - related emission properties whose peak position and efficiency depended on the loading of the polymer and on the mesomeric effects of the substituents.
p. 1056-1061
Received: 11 February 2009; in revised form: 25 February 2009 / Accepted: 3 March 2009 / Published: 5 March 2009
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| Download PDF Full-text (105 KB) Abstract: The three component reaction of primary aliphatic amines, glyoxalic acid and indole or N -methylindole in water at ambient temperature affords indol-3-yl or N -methylindol-3-yl-glycine in almost quantitative yields.
p. 1062-1071
Received: 27 November 2008; in revised form: 3 March 2009 / Accepted: 5 March 2009 / Published: 6 March 2009
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| Download PDF Full-text (238 KB) Abstract: Medicinal plants have long been used as a source of therapeutic agents. They are thought to be important anti-aging ingredients in prophylactic medicines. The aim of this study was to screen extracts from Taiwanese plant materials for phenolic contents and measure the corresponding matrix metalloproteinase-9 (MMP-9) activity. We extracted biological ingredients from eight plants native to Taiwan (Alnus formosana , Diospyros discolor , Eriobotrya deflex, Machilus japonica, Pyrrosia polydactylis , Pyrus taiwanensis , Vitis adstricta, Vitis thunbergii ). Total phenolic content was measured using the Folin-Ciocalteu method. MMP-9 activities were measured by gelatin zymography. The extracted yields of plants ranged from 3.7 % to 16.9 %. The total phenolic contents ranged from 25.4 to 36.8 mg GAE/g dry material. All of these extracts (except Vitis adstricta Hance) were shown to inhibit MMP-9 activity of WS-1 cell after ultraviolet B irradiation. These findings suggest that total phenolic content may influence MMP-9 activity and that some of the plants with higher phenolic content exhibited various biological activities that could serve as potent inhibitors of the ageing process in the skin. This property might be useful in the production of cosmetics.
p. 1072-1080
Received: 26 November 2008; in revised form: 30 December 2008 / Accepted: 21 January 2009 / Published: 9 March 2009
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| Download PDF Full-text (117 KB) Abstract: Around 20,000 snakebites are reported annually in Brazil and 90% of them are inflicted by species of the genus Bothrops . Intravenous administration of antibothropic antivenom neutralizes the systemic actions, but it is of little effect on the reversal of local symptoms and often induces adverse reactions, a context that drives the search for complementary treatments for snakebite accidents. Vegetable extracts with a range of antiophidian activities constitute an excellent alternative. In this study, we investigated the anti-hemorrhagic effects of Mouriri pusa Gardn. (Melastomataceae), Byrsonima crassa Niedenzu (Malpighiaceae), Davilla elliptica St. Hill. (Dilleniaceae) and Strychnos pseudoquina St. Hil. (Loganiaceae) against Bothrops jararaca venom. The methanolic extracts from M. pusa (leaves), B. crassa (leaves) and D. elliptica (leaves) showed total neutralization capacity against local hemorrhages. The amenthoflavone and quercetin fractions from B. crassa and the flavonoids fractions (quercetin and myricetin) from M. pusa and D. elliptica also showed total neutralization capacity. We conclude that flavonoids derived from myricetin, quercetin and amenthoflavone play an important role in the anti-hemorrhagic potential of these Brazilian vegetables species against B. jararaca venom.
p. 1081-1097
Received: 23 December 2008; in revised form: 3 March 2009 / Accepted: 4 March 2009 / Published: 9 March 2009
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| Download PDF Full-text (517 KB) Abstract: Changes in the physicochemical properties and structure of proteins derived from two malt varieties (Baudin and Guangmai) during wort boiling were investigated by differential scanning calorimetry, SDS-PAGE, two-dimensional electrophoresis, gel filtration chromatography and circular dichroism spectroscopy. The results showed that both protein content and amino acid composition changed only slightly during boiling, and that boiling might cause a gradual unfolding of protein structures, as indicated by the decrease in surface hydrophobicity and free sulfhydryl content and enthalpy value, as well as reduced α-helix contents and markedly increased random coil contents. It was also found that major component of both worts was a boiling-resistant protein with a molecular mass of 40 kDa, and that according to the two-dimensional electrophoresis and SE-HPLC analyses, a small amount of soluble aggregates might be formed via hydrophobic interactions. It was thus concluded that changes of protein structure caused by boiling that might influence beer quality are largely independent of malt variety.
p. 1098-1110
Received: 1 January 2009; in revised form: 12 January 2009 / Accepted: 22 January 2009 / Published: 10 March 2009
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| Download PDF Full-text (197 KB) Abstract: This study was designed to determine the gastroprotective effect of a Mangifera indica leaf decoction (AD), on different experimental models in rodents. The administration of AD up to a dose of 5 g/kg (p.o.) did not produce any signs or symptoms of toxicity in the treated animals, while significantly decreasing the severity of gastric damage induced by several gastroprotective models. Oral pre-treatment with AD (250, 500 or 1000 mg/kg) in mice and rats with gastric lesions induced by HCl/ethanol, absolute ethanol, non-steroidal anti-inflammatory drug (NSAID) or stress-induced gastric lesions resulted in a significant decrease of said lesions. Phytochemical analyses of AD composition demonstrated the presence of bioactive phenolic compounds that represent 57.3% of total phenolic content in this extract. Two main phenolic compounds were isolated, specifically mangiferin (C-glucopyranoside of 1,3,6,7-tetrahydroxyxanthone) and C-glucosyl-benzophenone (3-C-β-D-glucopyranosyl-4’,2,4,6-tetrahydroxybenzophenone). These findings indicate the potential gastroprotective properties of aqueous decoction from M. indica leaves.
p. 1111-1125
Received: 10 February 2009; in revised form: 10 March 2009 / Accepted: 11 March 2009 / Published: 12 March 2009
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| Download PDF Full-text (153 KB) Abstract: Laser radiation-induced decomposition of gaseous organic selenides and tellurides resulting in chemical deposition of nanostructured materials on cold surfaces is reviewed with regard to the mechanism of the gas-phase decomposition and properties of the deposited materials. The laser photolysis and laser thermolysis of the Se and Te precursors leading to chalcogen deposition can also serve as a useful approach to nanostructured chalcogen composites and IVA group (Si, Ge, Sn) element chalcogenides provided that it is carried out simultaneously with laser photolysis or thermolysis of polymer and IVA group element precursor.
p. 1126-1133
Received: 4 January 2009; in revised form: 20 January 2009 / Accepted: 17 February 2009 / Published: 12 March 2009
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| Download PDF Full-text (117 KB) Abstract: Phosphotungstic acid (H3 PW12 O40 ) was used as an efficient and recyclable catalyst for the synthesis of polysubstituted quinolines through the Friedländer condensation of 2-aminoarylketone with carbonyl compounds, which was achieved by conventional heating under solvent-free conditions.
p. 1134-1144
Published: 10 September 2009
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| Download PDF Full-text (21 KB) Abstract: Publisher's Note added on 10 September 2009: There is a pagination error in Molecules 2009, 14 (3) with pages 1134-1144 missing. Thus, pages 1134-1144 are taken as a blank pages.
p. 1145-1159
Josef Jampilek , Robert Musiol , Matus Pesko , Katarina Kralova , Marcela Vejsova , James Carroll , Aidan Coffey , Jacek Finster , Dominik Tabak , Halina Niedbala , Violetta Kozik , Jaroslaw Polanski , Jozef Csollei and Jiri Dohnal
Received: 4 February 2009; in revised form: 3 March 2009 / Accepted: 11 March 2009 / Published: 13 March 2009
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| Download PDF Full-text (180 KB) Abstract: In the study, a series of twelve ring-substituted 4-hydroxy-1H -quinolin-2-one derivatives were prepared. The procedures for synthesis of the compounds are presented. The compounds were analyzed using RP-HPLC to determine lipophilicity and tested for their photosynthesis-inhibiting activity using spinach (Spinacia oleracea L.) chloroplasts. All the synthesized compounds were also evaluated for antifungal activity using in vitro screening with eight fungal strains. For all the compounds, the relationships between the lipophilicity and the chemical structure of the studied compounds are discussed, as well as their structure-activity relationships (SAR).
p. 1160-1170
Received: 26 February 2009; in revised form: 10 March 2009 / Accepted: 11 March 2009 / Published: 16 March 2009
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| Download PDF Full-text (184 KB) Abstract: The effect of parabens on the shelf-life of crocetin esters and picrocrocin in aqueous saffron solutions was studied. Degradation of saffron crocetin esters fits a first-order kinetics model, and the results indicated that the crocetin (β -D-glucosyl)-(β -D-gentiobiosyl) esters were more stable than the crocetin di-(β -D-gentiobiosyl) esters regardless of whether trans and cis isomers were considered. Under all tested conditions both parabens gave good results, especially propyl paraben that showed a greater influence on the degradation rate constant, except for cis -crocetin di-(β -D-gentiobiosyl) ester and cis -crocetin (β -D-glucosyl)-(β -D-gentiobiosyl) ester. In presence of propyl paraben (200 mg/L), the half-life periods of trans -crocetin di-(β -D-gentiobiosyl) esterimproved considerably, up to four-fold. Special attention has been paid to the effect of propyl paraben on 46 saffrons with different crocetin ester contents. No differences were observed in terms of picrocrocin. By analysis of variance, it is noteworthy that there were differences between the mean content of crocetin esters for all analysed saffron, except for trans -crocetin (β -D-glucosyl)-(β -D-gentiobiosyl) ester.
p. 1171-1182
Received: 9 February 2009; in revised form: 27 February 2009 / Accepted: 11 March 2009 / Published: 16 March 2009
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| Download PDF Full-text (348 KB) Abstract: The chemical composition of the essential oil obtained from the leaves of Piper ovatum Vahl by hydrodistillation was analyzed by GC–MS. The main constituents found were δ -amorphene (16.5 %), cis -muurola-4(14),5-diene (14.29 %) and γ-muurolene (13.26%). The crude extracts and isolated compounds were screened for their antimicrobial activity. Hydroalcoholic extracts of different parts of Piper ovatum Vahl, essential oil and amides isolated from leaves were tested against Gram-positive and Gram-negative bacteria and Candida species. All extracts and amides were active against Bacillus subtilis and Candida tropicalis , including clinical strains. Essential oil was active against C. tropicalis . These amides showed an inhibitory effect on the adherence of C. tropicalis ATCC 28707 on cover glasses at 10 μg/mL, but did not show morphological alterations at the tested concentrations. Amides were identified as piperovatine and piperlonguminine, and showed MIC values of 15.6 and 31.2 μg/mL to B. subtilis and 3.9 μg/mL to C. tropicalis , and low toxic effects to Vero cells and macrophages.
p. 1183-1226
Received: 6 January 2009; in revised form: 27 February 2009 / Accepted: 10 March 2009 / Published: 23 March 2009
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| Download PDF Full-text (456 KB) Abstract: For the past few years more and more new cytotoxic agents active in the treatment of hematological malignancies have been synthesized and become available for either in vitro studies or clinical trials. Among them the class of antineoplastic drugs belonging to the purine nucleoside analogues group (PNAs) plays an important role. Three of them: pentostatin (DCF), cladribine (2-CdA) and fludarabine (FA) were approved by Food and Drug Administration (FDA) for the treatment of hematological malignancies. Recently three novel PNAs: clofarabine (CAFdA), nelarabine (ara-G) and forodesine (immucillin H, BCX-1777) have been synthesized and introduced into preclinical studies and clinical trials. These agents seem to be useful mainly for the treatment of human T-cell proliferative disorders and they are currently undergoing clinical trials in lymphoid malignancies. However, there are also several studies suggesting the role of these drugs in B-cell malignancies. This review will summarize current knowledge concerning the mechanism of action, pharmacologic properties, clinical activity and toxicity of PNAs accepted for use in clinical practice, as well as new agents available for clinical trials.
p. 1227-1233
Received: 23 December 2008; in revised form: 13 February 2009 / Accepted: 18 February 2009 / Published: 23 March 2009
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| Download PDF Full-text (182 KB) Abstract: The stem bark of Phoebe grandis afforded one new oxoproaporphine; (–)-grandine A (1), along with six known isoquinoline alkaloids: (–)-8,9-dihydrolinearisine (2), boldine, norboldine, lauformine, scortechiniine A and scortechiniine B. In addition to that of the new compound, complete 1 H- and 13 C-NMR data of the tetrahydroproaporphine (–)-8,9-dihydrolinearisine (2) is also reported. The alkaloids’ structures were elucidated primarily by means of high field 1D- and 2D-NMR and HRMS spectral data.
p. 1234-1244
Received: 3 November 2008; in revised form: 21 January 2009 / Accepted: 20 February 2009 / Published: 23 March 2009
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| Download PDF Full-text (330 KB) Abstract: The solid state structure of 1-((1H -benzotriazol-1-yl)methyl)naphthalen-2-ol, C17 H13 N3 O, shows that this Mannich base crystallizes forming intermolecular N···HO hydrogen bonds, rather than intramolecular ones. Factors contributing to this choice of hydrogen-bonding mode are discussed. The compound crystallizes in the monoclinic system, P21 /c space group, with lattice constants: a = 11.7934(9) Å, b = 14.3002(14) Å, c = 8.4444(8) Å, β = 106.243(5) deg, V = 1367.3(2) Å3 , Z = 4, F (000) = 576, R1 = 6.96%, wR2 = 11.4%.
p. 1245-1262
Received: 20 November 2008; in revised form: 11 February 2009 / Accepted: 2 March 2009 / Published: 23 March 2009
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| Download PDF Full-text (221 KB) Abstract: The genus Aristolochia ,an important source of physiologically active compounds that belong to different chemical classes, is the subject of research in numerous pharmacological and chemical studies. This genus contains a large number of terpenoid compounds, particularly diterpenes. This work presents a compilation of the 13 C-NMR data of 57 diterpenoids described between 1981 and 2007 which were isolated from Aristolochia species. The compounds are arranged skeletonwise in each section, according to their structures, i.e., clerodane, labdane, and kaurane derivatives. A brief discussion on the 13 C chemical shifts of these diterpenes is also included.
p. 1263-1278
Received: 30 January 2009; in revised form: 15 February 2009 / Accepted: 20 March 2009 / Published: 23 March 2009
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| Download PDF Full-text (205 KB) Abstract: Selenium is an essential trace element for humans and animals, and selenium deficiency is associated with several disease conditions such as immune impairment. In addition, selenium intakes that are greater than the recommended daily allowance (RDA) appear to protect against certain types of cancers. In humans and animals, cell proliferation and death must be regulated to maintain tissue homeostasis, and it has been well documented that numerous human diseases are directly related to the control of cell cycle progression and apoptosis. Thus, the elucidation of the mechanisms by which selenium regulates the cell cycle and apoptosis can lead to a better understanding of the nature of selenium’s essentiality and its role in disease prevention. This article reviews the status of knowledge concerning the effect of selenium on cell cycle and apoptosis
p. 1279-1287
Received: 26 December 2008; in revised form: 25 February 2009 / Accepted: 11 March 2009 / Published: 24 March 2009
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| Download PDF Full-text (105 KB) Abstract: Several strains of Thermus thermophilus were tested in order to detect purine nucleoside synthase activity using pyrimidine nucleosides as the sugar-donor and adenine or hypoxanthine as bases. High productivity values (t =1 hr) were obtained while completely avoiding adenosine-deaminase degradation of the products. N -2-deoxy-ribosyltransferase activity is described for the first time in hyperthermophilic bacteria.
p. 1288-1303
Received: 27 February 2009; in revised form: 12 March 2009 / Accepted: 16 March 2009 / Published: 24 March 2009
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| Download PDF Full-text (247 KB) Abstract: A series of novel 4-(4-(5-methyl-3-arylisoxazol-4-yl)thiazol-2-yl)piperidyl carboxamides and thiocarboxamides were synthesized as potential lead compounds of inhibitors targeting D1 protease in plants. These compounds were designed on the basis of a D1 protease inhibitor hit structure identified by homology modeling and virtual screening. The syntheses of these compounds were accomplished via a four-step procedure including the isoxazole ring formation, a-bromination of acetyl group, thiazole ring formation, and carboxamide/thiocarboxamide attachment. The in vivo herbicidal activity tests show that most compounds possess moderate to good herbicidal activities. The enzyme activity of one compound against the native spinach D1 protease exhibits a competitive inhibition. The results suggest that these compounds are indeed potential inhibitors for targeting D1 protease in plants.
p. 1304-1323
Received: 2 March 2009; in revised form: 23 March 2009 / Accepted: 24 March 2009 / Published: 25 March 2009
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| Download PDF Full-text (97 KB) Abstract: Antisense molecules do not readily cross cell membranes. This has limited the use of antisense to systems where techniques have been worked out to introduce the molecules into cells, such as embryos and cell cultures. Uncharged antisense bearing a group of guanidinium moieties on either a linear peptide or dendrimer scaffold can enter cells by endocytosis and subsequently escape from endosomes into the cytosol/nuclear compartment of cells. These technologies allow systemic administration of antisense, making gene knockdowns and splice modification feasible in adult animals; this review presents examples of such animal studies. Techniques developed with PPMOs, which are an arginine-rich cell-penetrating peptide linked to a Morpholino oligo, can also be performed using commercially available Vivo-Morpholinos, which are eight guanidinium groups on a dendrimeric scaffold linked to a Morpholino oligo. Antisense-based techniques such as blocking translation, modifying pre-mRNA splicing, inhibiting miRNA maturation and inhibiting viral replication can be conveniently applied in adult animals by injecting PPMOs or Vivo-Morpholinos.
p. 1324-1331
Received: 16 February 2009; in revised form: 11 March 2009 / Accepted: 13 March 2009 / Published: 25 March 2009
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| Download PDF Full-text (163 KB) Abstract: Forsythosides H-J (1-3), three new caffeoyl phenylethanoid glycosides (CPGs), were isolated from the fruits of Forsythia suspense (Thunb.) Vahl., together with six known phenylethanoid glycosides: Forsythoside A (4), Forsythoside F (5), Forsythoside E (6), 2-(3,4-dihydroxyphenyl)ethyl-β -D-glucopyranoside (7), phenethyl alcohol β -D-xylo-pyranosyl-(1→6)-β -D-glucopyranoside (8) and calceolarioside B (9). Their structures were determined by spectroscopic and chemical methods.
p. 1332-1341
Received: 21 November 2008; in revised form: 18 February 2009 / Accepted: 11 March 2009 / Published: 26 March 2009
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| Download PDF Full-text (144 KB) Abstract: The crude ethanolic extract and n -hexane, dichloromethane, ethyl acetate, n -butanol and aqueous fractions of Dodonaea viscosa were analyzed for antibacterial potential against four Gram positive bacteria: Bacillus subtilis, Bacillus cereus, Micrococcus luteus, Staphylococcus aureus, and three Gram negative bacteria: Escherichia coli, Salmonella typhi, Pseudomonas aeruginosa . Preliminary screening showed inhibition against Staphylococcus aureus , Micrococcus luteus, Escherichia coli and Pseudomonas aeruginosa . The thin layer chromatograms of the fractions were then subjected to contact bioautography, which showed inhibition zone at different Rf values against Bacillus subtilis, Micrococcus luteus, Escherichia coli, Salmonella typhi and Pseudomonas aeruginosa, indicating the presence of antibacterial components. The MIC of each fraction was determined through a 96-well micro-titer plate method. The non-viability of the organisms was ascertained by determining the MBC of the fractions.
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