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Molecules, Volume 14, Issue 7 (July 2009), Pages 2306-2683

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Open AccessArticle Synthesis and Antitumor Evaluation of Novel Bis-Triaziquone Derivatives
Molecules 2009, 14(7), 2306-2316; doi:10.3390/molecules14072306
Received: 30 April 2009 / Revised: 19 June 2009 / Accepted: 23 June 2009 / Published: 29 June 2009
Cited by 5 | PDF Full-text (268 KB) | HTML Full-text | XML Full-text
Abstract
Aziridine-containing compounds have been of interest as anticancer agents since late 1970s. The design, synthesis and study of triaziquone (TZQ) analogues with the aim of obtaining compounds with enhanced efficacy and reduced toxicity are an ongoing research effort in our group. A [...] Read more.
Aziridine-containing compounds have been of interest as anticancer agents since late 1970s. The design, synthesis and study of triaziquone (TZQ) analogues with the aim of obtaining compounds with enhanced efficacy and reduced toxicity are an ongoing research effort in our group. A series of bis-type TZQ derivatives has been prepared and their cytotoxic activities were investigated. The cytotoxicity of these bis-type TZQ derivatives were tested on three cancer lines, including breast cancer (BC-M1), oral cancer (OEC-M1), larynx epidermal cancer (Hep2) and one normal skin fibroblast (SF). Most of these synthetic derivatives displayed significant cytotoxic activities against human carcinoma cell lines, but weak activities against SF. Among tested analogues the bis-type TZQ derivative 1a showed lethal effects on larynx epidermal carcinoma cells (Hep2), with an LC50 value of 2.02 mM, and also weak cytotoxic activity against SF cells with an LC50 value over 10 mM for 24 hr treatment. Comparing the viability of normal fibroblast cells treated with compound 1a and TZQ, the LC50 value of the latter was 2.52 mM, indicating more toxicity than compound 1a. This significantly decreased cytotoxicity of compound 1a towards normal SF cells, while still maintaining the anticancer activity towards Hep2 cells is an interesting feature. Among the seven compounds synthesized, compound 1c has similar toxicity effects on the three cancer cell lines and SF normal cells as the TZQ monomer. Full article
Open AccessArticle A New Synthetic Compound, 2-OH, Enhances Interleukin-2 and Interferon-γ Gene Expression in Human Peripheral Blood Mononuclear Cells
Molecules 2009, 14(7), 2345-2355; doi:10.3390/molecules14072345
Received: 7 May 2009 / Revised: 17 June 2009 / Accepted: 29 June 2009 / Published: 2 July 2009
Cited by 7 | PDF Full-text (260 KB) | HTML Full-text | XML Full-text
Abstract
A new synthetic compound, 6-hydroxy-2-tosylisoquinolin-1(2H)-one (2-OH), was selected for immunopharmacological activity tests. The effects of 2-OH on human peripheral blood mononuclear cell (PBMC) proliferation were determined by tritiated thymidine uptake. Compared to phytohemagglutinin (PHA; 5 μg/mL) stimulation, 2-OH significantly enhanced [...] Read more.
A new synthetic compound, 6-hydroxy-2-tosylisoquinolin-1(2H)-one (2-OH), was selected for immunopharmacological activity tests. The effects of 2-OH on human peripheral blood mononuclear cell (PBMC) proliferation were determined by tritiated thymidine uptake. Compared to phytohemagglutinin (PHA; 5 μg/mL) stimulation, 2-OH significantly enhanced PBMC proliferation in a dose-dependent manner. The 50% enhancement activity (EC50) for 2-OH was 4.4±0.1 μM. In addition, effects of 2-OH on interleukin-2 (IL-2) and interferon-γ (IFN-γ) production in PBMC were determined by enzyme immunoassay. Results demonstrated that 2-OH stimulated IL-2 and IFN-γ production in PBMC. Data from reverse transcription-polymerase chain reaction (RT-PCR) and real-time PCR indicated that IL-2 and IFN-γ mRNA expression in PBMC could be induced by 2-OH. Therefore, 2-OH enhanced IL-2 and IFN-γ production in PBMC by modulation their gene expression. We suggest that 2-OH may be an immunomodulatory agent. Full article
Open AccessArticle The Reaction of 4,5-Dichloro-1,2,3-dithiazolium Chloride with Sulfimides: A New Synthesis of N-Aryl-1,2,3-dithiazolimines
Molecules 2009, 14(7), 2356-2362; doi:10.3390/molecules14072356
Received: 26 May 2009 / Revised: 10 June 2009 / Accepted: 12 June 2009 / Published: 2 July 2009
Cited by 2 | PDF Full-text (138 KB) | HTML Full-text | XML Full-text
Abstract
N-Aryl-S,S-dimethylsulfimides 3(Ar = 4-NO2C6H4), 4 (Ar = Ph) and 5 (Ar = 4-Tol)react with Appel salt 1 to give the corresponding N-aryl-(4-chloro-5H-1,2,3-dithiazolylidene)benzenamines 8 (Ar = 4-NO2C [...] Read more.
N-Aryl-S,S-dimethylsulfimides 3(Ar = 4-NO2C6H4), 4 (Ar = Ph) and 5 (Ar = 4-Tol)react with Appel salt 1 to give the corresponding N-aryl-(4-chloro-5H-1,2,3-dithiazolylidene)benzenamines 8 (Ar = 4-NO2C6H4), 9 (Ar = Ph) and 10 (Ar = 4-Tol) in 84, 94 and 87% yields, respectively. The reaction proceeds in the absence of base and a proposed reaction mechanism is given. Full article
(This article belongs to the Special Issue Advances in Heterocyclic Chemistry)
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Open AccessArticle Salivary Aldehyde Dehydrogenase: Activity towards Aromatic Aldehydes and Comparison with Recombinant ALDH3A1
Molecules 2009, 14(7), 2363-2372; doi:10.3390/molecules14072363
Received: 11 May 2009 / Revised: 15 June 2009 / Accepted: 18 June 2009 / Published: 2 July 2009
Cited by 5 | PDF Full-text (421 KB) | HTML Full-text | XML Full-text
Abstract
A series of aromatic aldehydes was examined as substrates for salivary aldehyde dehydrogenase (sALDH) and the recombinant ALDH3A1. Para-substituted benzaldehydes, cinnamic aldehyde and 2-naphthaldehydes were found to be excellent substrates, and kinetic parameters for both salivary and recombinant ALDH were nearly identical. [...] Read more.
A series of aromatic aldehydes was examined as substrates for salivary aldehyde dehydrogenase (sALDH) and the recombinant ALDH3A1. Para-substituted benzaldehydes, cinnamic aldehyde and 2-naphthaldehydes were found to be excellent substrates, and kinetic parameters for both salivary and recombinant ALDH were nearly identical. It was demonstrated that for the fluorogenic naphthaldehydes the only produced reaction product after incubation in saliva is the carboxylate. Full article
Open AccessArticle Transformations of Organic Molecules with F-TEDA-BF4 in Ionic Liquid Media
Molecules 2009, 14(7), 2394-2409; doi:10.3390/molecules14072394
Received: 11 May 2009 / Revised: 10 June 2009 / Accepted: 3 July 2009 / Published: 6 July 2009
Cited by 10 | PDF Full-text (217 KB) | HTML Full-text | XML Full-text
Abstract
The transformations of organic molecules with F-TEDA-BF4 (1) were investigated in the hydrophilic ionic liquid (IL) 1-butyl-3-methyl-imidazolium tetrafluoroborate ([bmim][BF4], 2) and the hydrophobic IL 1-butyl-3-methyl-imidazolium hexafluorophosphate ([bmim][PF6], 3). The range of substrates included alkyl substituted phenols 4a-c, [...] Read more.
The transformations of organic molecules with F-TEDA-BF4 (1) were investigated in the hydrophilic ionic liquid (IL) 1-butyl-3-methyl-imidazolium tetrafluoroborate ([bmim][BF4], 2) and the hydrophobic IL 1-butyl-3-methyl-imidazolium hexafluorophosphate ([bmim][PF6], 3). The range of substrates included alkyl substituted phenols 4a-c, 9, 13, 1,1-diphenylethene (15), alkyl aryl ketones 19-22, aldehydes 23-25 and methoxy-substituted benzene derivatives 26-30. The evaluation of the outcome of reactions performed in IL media in comparison to those of the corresponding reactions in conventional organic solvents revealed that the transformations in IL are less efficient and selective. The effect of the presence of a nucleophile (MeOH, H2O, MeCN) on the course of reaction was also studied. Full article
(This article belongs to the Special Issue Ionic Liquids)
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Open AccessArticle Novel Biodegradable Polyesters. Synthesis and Application as Drug Carriers for the Preparation of Raloxifene HCl Loaded Nanoparticles
Molecules 2009, 14(7), 2410-2430; doi:10.3390/molecules14072410
Received: 5 June 2009 / Revised: 2 July 2009 / Accepted: 6 July 2009 / Published: 7 July 2009
Cited by 16 | PDF Full-text (549 KB) | HTML Full-text | XML Full-text
Abstract
Raloxifene HCl is a drug with poor bioavailability and poor water solubility. Furthermore nο pharmaceutically acceptable organic solvent has been reported before to dilute the drug. It was observed that Raloxifene HCl can be diluted in a solvent mixture of acetone/water or [...] Read more.
Raloxifene HCl is a drug with poor bioavailability and poor water solubility. Furthermore nο pharmaceutically acceptable organic solvent has been reported before to dilute the drug. It was observed that Raloxifene HCl can be diluted in a solvent mixture of acetone/water or ethanol/water. The aim of this study was to use biodegradable polymers in order to prepare Raloxifene HCl nanoparticles. For this purpose a series of novel biodegradable poly(ethylene succinate-co-propylene adipate) P(ESu-co-PAd) polyesters were synthesized following the polycondensation method and further, poly(ethylene succinate) (PESu) and poly(propylene adipate) (PPAd) were used. The prepared polyesters were characterized by intrinsic viscosity measurements, end group analysis, enzymatic hydrolysis, Nuclear Magnetic Resonance Spectroscopy (1Η-NMR and 13C-NMR) and Wide-angle X-ray Diffractometry (WAXD). The drug nanoparticles have been prepared by a variation of the co-precipitation method and were studied by Wide-angle X-ray Diffractometry (WAXD), FTIR spectrometry, light scattering size distribution, Scanning Electron Microscopy (SEM) and release behavior measurements. The interactions between the polymers and the drug seem to be limited, so the drug occurs in crystalline form in all nanoparticles. The size of the nanoparticles seems to be in the range of 150-350 nm, depending on the polymer that was used. The drug release depends on the melting point and degree of crystallinity of the polyesters used. An initial high release rate was recorded followed by very slow rates of controlled release. Full article
(This article belongs to the Special Issue Macromolecules Applied to Pharmaceutics)
Open AccessArticle Synthesis and Antibacterial Activities of New Metronidazole and Imidazole Derivatives
Molecules 2009, 14(7), 2431-2446; doi:10.3390/molecules14072431
Received: 17 May 2009 / Revised: 12 June 2009 / Accepted: 6 July 2009 / Published: 8 July 2009
Cited by 24 | PDF Full-text (191 KB) | HTML Full-text | XML Full-text
Abstract
New imidazole ring derivatives comprising 1,3-oxazoline, Schiff's bases, thiadiazole, oxadiazole and 1,2,4-triazole moieties are reported. 3-Aminobiimidazol-4-one compounds 7a-c were synthesized by the reaction of compounds 6a-c with hydrazine hydrate. Biimidazole esters 9a-c were converted into biimidazole hydrazide esters 10a-c. Compounds 7a-c and [...] Read more.
New imidazole ring derivatives comprising 1,3-oxazoline, Schiff's bases, thiadiazole, oxadiazole and 1,2,4-triazole moieties are reported. 3-Aminobiimidazol-4-one compounds 7a-c were synthesized by the reaction of compounds 6a-c with hydrazine hydrate. Biimidazole esters 9a-c were converted into biimidazole hydrazide esters 10a-c. Compounds 7a-c and 10a-c were converted into a variety of derivatives. Full article
Open AccessArticle Synthesis of 3-N-Sugar-substituted-2, 4(1H,3H)-quinazolinedionesas Anti-Angiogenesis Agents
Molecules 2009, 14(7), 2447-2457; doi:10.3390/molecules14072447
Received: 8 May 2009 / Revised: 27 May 2009 / Accepted: 2 June 2009 / Published: 8 July 2009
Cited by 5 | PDF Full-text (267 KB) | HTML Full-text | XML Full-text
Abstract A series of novel 3-N-sugar-substituted quinazolinediones were synthesizedthrough the cyclization of the intermediate 2-aminobenzamides using triphosgene as the condensing reagent. Their anti-angiogenesis activities were investigated. The compound 3-(2'-aminoglucosyl)-2,4-(1H,3H)-quinazolinedione, (5d) showed good anti-angiogenesis activity. Full article
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Open AccessArticle Chemical Composition of the Essential Oils from the Roots of Erigeron acris L. and Erigeron annuus (L.) Pers.
Molecules 2009, 14(7), 2458-2465; doi:10.3390/molecules14072458
Received: 22 May 2009 / Revised: 25 June 2009 / Accepted: 8 July 2009 / Published: 9 July 2009
Cited by 11 | PDF Full-text (176 KB) | HTML Full-text | XML Full-text
Abstract
The chemical compositions of essential oils from the roots of Erigeron acris and Erigeron annuus were studied. The essential oils were obtained by hydrodistillation in 1.0% and 0.05% yield, respectively, and analyzed by GC, GC-MS. Fifty four and forty seven constituents were [...] Read more.
The chemical compositions of essential oils from the roots of Erigeron acris and Erigeron annuus were studied. The essential oils were obtained by hydrodistillation in 1.0% and 0.05% yield, respectively, and analyzed by GC, GC-MS. Fifty four and forty seven constituents were identified. Predominant constituents of both oils were poly-acetylene esters: (Z,Z)-matricaria ester (49.4% and 45.9%, respectively) and (Z)-lachnophyllum ester (37.2% and 27.5%, respectively), that were accompanied by their stereoisomers as well as appropriate lactones. Polyacetylenic compounds amounted to 92.1% of E. acris oil and 85.8% of E. annuus oil. Both oils contained the same monoterpene hydrocarbons, amounting to 4.2% and 5.8%, respectively, and traces of almost the same monoterpene oxygenated compounds. The dominant sesquiterpenes in E. acris were elemenes and tricyclic sesquiterpene hydrocarbons, while in E. annuus β-sesquiphellandrene and β-bisabolene dominated. After flash chromatography of essential oil from E. acris, fractions contained acetylene esters and acetylene lactones were obtained. The configuration about double bonds for these compounds has been elucidated on the basis of 1H- and 13C-NMR analysis. Full article
Open AccessArticle Identification and Quantification of Flavonoids and Phenolic Acids in Burr Parsley (Caucalis platycarpos L.), Using High-Performance Liquid Chromatography with Diode Array Detection and Electrospray Ionization Mass Spectrometry
Molecules 2009, 14(7), 2466-2490; doi:10.3390/molecules14072466
Received: 8 June 2009 / Revised: 25 June 2009 / Accepted: 6 July 2009 / Published: 9 July 2009
Cited by 62 | PDF Full-text (839 KB) | HTML Full-text | XML Full-text
Abstract
A sensitive method coupling high-performance liquid chromatography (HPLC) with diode-array detector (DAD) and electrospray ionization mass spectrometry (MS) was optimized for the separation and identification of phenolic acids, flavonoid glycosides and flavonoid aglycones in the extract of burr parsley (Caucalis platycarpos [...] Read more.
A sensitive method coupling high-performance liquid chromatography (HPLC) with diode-array detector (DAD) and electrospray ionization mass spectrometry (MS) was optimized for the separation and identification of phenolic acids, flavonoid glycosides and flavonoid aglycones in the extract of burr parsley (Caucalis platycarpos L.). Fragmentation behavior of flavonoid glycosides and phenolic acids were investigated using ion trap mass spectrometry in negative electrospray ionization. The MS, MSn and UV data together with HPLC retention time (TR) of phenolic acids and flavonoids allowed structural characterization of these compounds. Caffeoylquinic acid (CQA) isomers, p-coumaroyl-quinic acids (p-CoQA), feruloylquinic acids (FQA), dicaffeoylquinic acids (diCQA), luteolin-7-O-rutinoside, apigenin-7-O-rutinoside as well as isolated chrysoeriol-7-O-rutinoside have been identified as constituents of C. platycarpos for the first time. An accurate, precise and sensitive LC-DAD method for quantification of four phenolic acids (3-O-caffeoylquinic, caffeic, p-coumaric, o-coumaric acid), four flavonoid glycosides (luteolin-7-O-glucoside, apigenin-7-O-glucoside, quercetin-3-O-galactoside, quercetin-3-O-rhamnoside), and three flavonoid aglycones (luteolin, apigenin, chrysoeriol) in C. platycarpos extract was validated in terms of linearity, limit of detection, limit of quantification, precision and accuracy. 3-O-caffeoylquinic acid was the predominant phenolic acid and luteolin-7-O-glucoside was the predominant flavonoid glycoside. Full article
Open AccessArticle Leishmanicidal Activity of Aliphatic and Aromatic Lactones: Correlation Structure-Activity
Molecules 2009, 14(7), 2491-2500; doi:10.3390/molecules14072491
Received: 7 June 2009 / Accepted: 18 June 2009 / Published: 10 July 2009
Cited by 9 | PDF Full-text (221 KB) | HTML Full-text | XML Full-text
Abstract
Several aliphatic and aromatic lactones and two dimers were synthesized using the sequence: allylation - esterification - metathesis. These compounds were active in vitro against intracellular amastigotes of Leishmania panamensis. The structure-activity relationship showed the importance of the aliphatic side chain [...] Read more.
Several aliphatic and aromatic lactones and two dimers were synthesized using the sequence: allylation - esterification - metathesis. These compounds were active in vitro against intracellular amastigotes of Leishmania panamensis. The structure-activity relationship showed the importance of the aliphatic side chain to enhance the biological activity and to obtain lower cytotoxicity. It was also observed that a decrease in the size of the lactone ring increases the selectivity index. Full article
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Open AccessArticle Design and Synthesis of Some Thiazolidin-4-ones Based on (7-Hydroxy-2-oxo-2H-chromen-4-yl) Acetic Acid
Molecules 2009, 14(7), 2501-2513; doi:10.3390/molecules14072501
Received: 27 May 2009 / Revised: 7 July 2009 / Accepted: 8 July 2009 / Published: 10 July 2009
Cited by 9 | PDF Full-text (234 KB) | HTML Full-text | XML Full-text
Abstract
(7-Hydroxy-2-oxo-2H-chromen-4-yl)-acetic acid methyl ester(1) upon reaction with ethyl bromoacetate furnishes (7-ethoxycarbonylmethoxy-2-oxo-2H-chromen-4-yl)-acetic acid methylester (2), which on treatment with 100% hydrazine hydrate yields (7-hydrazinocarbonylmethoxy-2-oxo-2H-chromen-4-yl)-acetic acid hydrazide (3). The condensation of compound 3 with different aromatic aldehydes afforded [...] Read more.
(7-Hydroxy-2-oxo-2H-chromen-4-yl)-acetic acid methyl ester(1) upon reaction with ethyl bromoacetate furnishes (7-ethoxycarbonylmethoxy-2-oxo-2H-chromen-4-yl)-acetic acid methylester (2), which on treatment with 100% hydrazine hydrate yields (7-hydrazinocarbonylmethoxy-2-oxo-2H-chromen-4-yl)-acetic acid hydrazide (3). The condensation of compound 3 with different aromatic aldehydes afforded a series of [7-(arylidenehydrazinocarbonylmethoxy)-2-oxo-2H-chromen-4-yl]-acetic acid arylidene-hydrazide Schiff’s bases 4a-k. Cyclo-condensation of compounds 4a-k with 2-mercapto-acetic acid in N,N-dimethylformamide in the presence of anhydrous ZnCl2 affordsN-(2-aryl-4-oxothiazolidin-3-yl)-2-(4-(2-aryl-4-oxothiazolidin-3-ylcarbamoyl)-methyl)-2-oxo-2H-chromen-7-yloxy)-acetamides 5a-k. Structure elucidation of the products has been accomplished on the basis of elemental analysis, IR, 1H-NMR and 13C-NMR data. Compounds 4a-k and 5a-k will be screened for their antibacterial activity against both Gram-positive and Gram-negative bacteria and the results reported elsewhere in due course. Full article
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Open AccessArticle Tyrosinase Inhibitor Activity of Coumarin-Resveratrol Hybrids
Molecules 2009, 14(7), 2514-2520; doi:10.3390/molecules14072514
Received: 11 May 2009 / Revised: 9 July 2009 / Accepted: 10 July 2009 / Published: 13 July 2009
Cited by 21 | PDF Full-text (243 KB) | HTML Full-text | XML Full-text
Abstract
In the present work we report on the contribution of the coumarin moiety to tyrosinase inhibition. Coumarin-resveratrol hybrids 1-8 have been resynthesized to investigate the structure-activity relationships and the IC50 values of these compounds were measured. The results showed that these [...] Read more.
In the present work we report on the contribution of the coumarin moiety to tyrosinase inhibition. Coumarin-resveratrol hybrids 1-8 have been resynthesized to investigate the structure-activity relationships and the IC50 values of these compounds were measured. The results showed that these compounds exhibited tyrosinase inhibitory activity. Compound 3-(3’,4’,5’-trihydroxyphenyl)-6,8-dihydroxycoumarin (8)is the most potentcompound (0.27 mM), more so than umbelliferone (0.42 mM), used as reference compound. The kinetic studies revealed that compound 8 caused non-competitive tyrosinase inhibition. Full article
(This article belongs to the Special Issue Coumarins and Xanthones)
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Open AccessArticle Ionic Liquids: Just Molten Salts After All?
Molecules 2009, 14(7), 2521-2534; doi:10.3390/molecules14072521
Received: 7 June 2009 / Revised: 6 July 2009 / Accepted: 10 July 2009 / Published: 13 July 2009
Cited by 31 | PDF Full-text (348 KB) | HTML Full-text | XML Full-text
Abstract
While there has been much effort in recent years to characterise ionic liquids in terms of parameters that are well described for molecular solvents, using these to explain reaction outcomes remains problematic. Herein we propose that many reaction outcomes in ionic liquids [...] Read more.
While there has been much effort in recent years to characterise ionic liquids in terms of parameters that are well described for molecular solvents, using these to explain reaction outcomes remains problematic. Herein we propose that many reaction outcomes in ionic liquids may be explained by considering the electrostatic interactions present in the solution; that is, by recognising that ionic liquids are salts. This is supported by evidence in the literature, along with studies presented here. Full article
(This article belongs to the Special Issue Ionic Liquids)
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Open AccessArticle Diaroyl Tellurides: Synthesis, Structure and NBO Analysis of (2-MeOC6H4CO)2Te – Comparison with Its Sulfur and Selenium Isologues. The First Observation of [MgBr][R(C=Te)O] Salts
Molecules 2009, 14(7), 2555-2572; doi:10.3390/molecules14072555
Received: 3 June 2009 / Revised: 7 July 2009 / Accepted: 9 July 2009 / Published: 13 July 2009
Cited by 3 | PDF Full-text (580 KB) | HTML Full-text | XML Full-text
Abstract
A series of aromatic diacyl tellurides were prepared in moderate to good yields by the reactions of sodium orpotassium arenecarbotelluroates with acyl chlorides in acetonitrile. X-ray structure analyses and theoretical calculations of 2-methoxybenzoic anhydride and bis(2-methoxybenzoyl) sulfide, selenide and telluride were carried [...] Read more.
A series of aromatic diacyl tellurides were prepared in moderate to good yields by the reactions of sodium orpotassium arenecarbotelluroates with acyl chlorides in acetonitrile. X-ray structure analyses and theoretical calculations of 2-methoxybenzoic anhydride and bis(2-methoxybenzoyl) sulfide, selenide and telluride were carried out. The two 2-MeOC6H4CO moieties of bis(2-methoxybenzoyl) telluride are nearly planar and the two methoxy oxygen atoms intramolecularly coordinate to the central tellurium atom from both side of C(11)-Te(11)-C(22) plane. In contrast, the oxygen and sulfur isologues (2-MeOC6H4CO)2E (E = O, S), show that one of the two methoxy oxygen atoms contacts with the oxygen atom of the carbonyl group connected to the same benzene ring. The structure of di(2-methoxybenzoyl) selenide which was obtained by MO calculation resembles that of tellurium isologues rather than the corresponding oxygen and sulfur isologues. The reactions of di(aroyl) tellurides with Grignard reagents lead to the formation of tellurocarboxylato magnesium complexes [MgBr][R(C=Te)O]. Full article
(This article belongs to the Special Issue Selenium and Tellurium Chemistry)
Open AccessArticle Extraction of Oil from Wheat Germ by Supercritical CO2
Molecules 2009, 14(7), 2573-2581; doi:10.3390/molecules14072573
Received: 26 May 2009 / Revised: 30 June 2009 / Accepted: 13 July 2009 / Published: 15 July 2009
Cited by 17 | PDF Full-text (116 KB) | HTML Full-text | XML Full-text
Abstract
This study examined the supercritical fluid extraction of wheat germ oil. The effects of pressure (200-300 bar at 40 °C) and extraction time on the oil quality/quantity were studied. A comparison was also made between the relative qualities of material obtained by [...] Read more.
This study examined the supercritical fluid extraction of wheat germ oil. The effects of pressure (200-300 bar at 40 °C) and extraction time on the oil quality/quantity were studied. A comparison was also made between the relative qualities of material obtained by SFE and by organic solvent extraction. The extracts were analyzed for α-tocopherol and polyunsaturated fatty acid content. The maximum wheat germ oil yield at about 9% was obtained with supercritical carbon dioxide extraction at 300 bar, while fatty acid and α-tocopherol composition of the extracts was not remarkable affected by either pressure or the extraction method. Full article
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Open AccessArticle Synthesis, Crystal Structure, and Kinetics of the Thermal Decomposition of the Nickel(II) Complex of the Schiff Base 2-[(4 Methylphenylimino)methyl]-6-methoxyphenol
Molecules 2009, 14(7), 2582-2593; doi:10.3390/molecules14072582
Received: 11 May 2009 / Revised: 29 June 2009 / Accepted: 8 July 2009 / Published: 15 July 2009
Cited by 16 | PDF Full-text (340 KB) | HTML Full-text | XML Full-text
Abstract
A new dinuclear complex, [Ni2(H2O)L4]·5H2O, consisting of chelating bidentate and bridging tridentate coordinated 2-[(4-methylphenylimino)methyl]-6-methoxyphenol (HL) Schiff base ligands and water molecules has been synthesized using a traditional method. The structure of this complex was [...] Read more.
A new dinuclear complex, [Ni2(H2O)L4]·5H2O, consisting of chelating bidentate and bridging tridentate coordinated 2-[(4-methylphenylimino)methyl]-6-methoxyphenol (HL) Schiff base ligands and water molecules has been synthesized using a traditional method. The structure of this complex was characterized by FTIR and UV/Vis spectroscopy and thermogravimetric analyses (TG-DTG) and further confirmed by single-crystal X-ray diffraction. Its crystal structure is of monoclinic system, space group P21/c with a = 13.2837(5) Å, b = 27.3886(10) Å, c = 17.5415(6) Å, α = 90 º, β = 108.429(2) º, γ = 90 º, V = 6054.7(4) Å3, Z = 4. The crystal structure reveals that there is a Ni·Ni core, with a separation of 3.183 Å. Its thermal decomposition kinetics were also studied. Full article
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Open AccessArticle Calixpyrrole Derivatives: “Multi Hydrogen Bond” Catalysts for γ-Butenolide Synthesis
Molecules 2009, 14(7), 2594-2601; doi:10.3390/molecules14072594
Received: 22 May 2009 / Revised: 7 July 2009 / Accepted: 9 July 2009 / Published: 15 July 2009
Cited by 8 | PDF Full-text (156 KB) | HTML Full-text | XML Full-text
Abstract
Calix[4]pyrrole (1), calix[2]m-benzo[4]pyrrole (2), 10α,20β- and 10α,20α- bis(4-nitrophenyl)-calix[4]pyrroles 3 and 4, respectively, were found to exhibit various organocatalytic activities in the diastereoselective vinylogous addition reaction of 2-trimethylsilyloxyfuran (TMSOF, 7) to aldehydes. The γ-hydroxybutenolide products are obtained in fairly good yields [...] Read more.
Calix[4]pyrrole (1), calix[2]m-benzo[4]pyrrole (2), 10α,20β- and 10α,20α- bis(4-nitrophenyl)-calix[4]pyrroles 3 and 4, respectively, were found to exhibit various organocatalytic activities in the diastereoselective vinylogous addition reaction of 2-trimethylsilyloxyfuran (TMSOF, 7) to aldehydes. The γ-hydroxybutenolide products are obtained in fairly good yields and with moderate diastereoselectivity. The structures of the catalysts, as well as the reaction conditions, strongly influence the efficiency of the reaction. Full article
(This article belongs to the Special Issue Organocatalysis)
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Open AccessArticle Synthesis and Biological Activity of Some New 1,3,4-Thiadiazole and 1,2,4-Triazole Compounds Containing a Phenylalanine Moiety
Molecules 2009, 14(7), 2621-2631; doi:10.3390/molecules14072621
Received: 11 May 2009 / Revised: 24 June 2009 / Accepted: 8 July 2009 / Published: 16 July 2009
Cited by 39 | PDF Full-text (138 KB) | HTML Full-text | XML Full-text
Abstract
New 1,3,4-thiadiazole, 6, 7 and 1,2,4-triazole derivatives, 8, 9 containing a phenylalanine moiety have been synthesized by intramolecular cyclization of 1,4-disubstituted thiosemicarbazides, 4, 5, in acid and alkaline media, respectively; the thiosemicarbazides were obtained by reaction of hydrazide 3 with appropriate aromatic [...] Read more.
New 1,3,4-thiadiazole, 6, 7 and 1,2,4-triazole derivatives, 8, 9 containing a phenylalanine moiety have been synthesized by intramolecular cyclization of 1,4-disubstituted thiosemicarbazides, 4, 5, in acid and alkaline media, respectively; the thiosemicarbazides were obtained by reaction of hydrazide 3 with appropriate aromatic isothiocyanates. The toxicity of the synthesized compounds was evaluated and the anti-inflammatory study of the triazole compound 9 established an appreciable anti-inflammatory activity that is comparable with that of other nonsteroidal anti-inflammatory agents. Full article
Open AccessArticle Experimental and Computational Studies on Non-Covalent Imprinted Microspheres as Recognition System for Nicotinamide Molecules
Molecules 2009, 14(7), 2632-2649; doi:10.3390/molecules14072632
Received: 4 June 2009 / Revised: 29 June 2009 / Accepted: 3 July 2009 / Published: 17 July 2009
Cited by 18 | PDF Full-text (638 KB) | HTML Full-text | XML Full-text
Abstract
Molecularly imprinted microspheres obtained by precipitation polymerization using nicotinamide (nia) as template have been prepared and characterised by SEM. How various experimental parameters can affect microsphere morphology, reaction yield and re-binding capacity have been evaluated. Pre-polymerization interactions between template and functional monomer [...] Read more.
Molecularly imprinted microspheres obtained by precipitation polymerization using nicotinamide (nia) as template have been prepared and characterised by SEM. How various experimental parameters can affect microsphere morphology, reaction yield and re-binding capacity have been evaluated. Pre-polymerization interactions between template and functional monomer in chloroform and MeCN have been studied by 1H-NMR. The results suggest that the interaction between nia and methacrylic acid (MAA) is mainly based on hydrogen-bonding between amide protons and MAA. Computational density functional theory (DFT) studies on MAA-nia complexes have been also performed to better understand hydrogen-bonding interactions. The imprinted activity of the microspheres, synthesized in chloroform or acetonitrile (MeCN), has been evaluated by spectrophotometric analysis of nia solutions when chloroform or MeCN are used as incubation solvents. The results suggest that MeCN interferes with hydrogen bonding between template and MAA during either the polymerization step or re-binding process as also observed from theoretical results. Finally, the selectivity towards selected nia analogues has been also confirmed. Full article
Open AccessArticle A New Friedelane Type Triterpene from Euonymus hederaceus
Molecules 2009, 14(7), 2650-2655; doi:10.3390/molecules14072650
Received: 22 June 2009 / Revised: 10 July 2009 / Accepted: 15 July 2009 / Published: 17 July 2009
Cited by 7 | PDF Full-text (144 KB) | HTML Full-text | XML Full-text
Abstract
Euonymus hederaceus is distributed widely in the south of China; its stems and leaves have been used as folk medicines to treat many diseases such as renal deficiency and chronic diarrhea, traumatic injury, and abnormal menstruation. Chemical investigation of the leaves and [...] Read more.
Euonymus hederaceus is distributed widely in the south of China; its stems and leaves have been used as folk medicines to treat many diseases such as renal deficiency and chronic diarrhea, traumatic injury, and abnormal menstruation. Chemical investigation of the leaves and stems of Euonymus hederaceus resulted in the isolation forthe first time and characterization of a new friedelane type triterpene with a molecular mass of 472 and molecular formula of C30H48O4 by high resolution mass spectrometry. The 1H-NMR 13C-NMR and DEPT1350 spectra matched the characteristic data of the proposed triterpene skeleton.The compound was finally identified as 28-hydroxyfriedelan-3-one-29-oic acid on the basis of spectroscopic evidence, including two dimensional nuclear magnetic resonance as well as its IR spectrum. Full article
Open AccessArticle Electronic Structure of the Azide Group in 3¢-Azido-3¢-deoxythymidine (AZT) Compared to Small Azide Compounds
Molecules 2009, 14(7), 2656-2668; doi:10.3390/molecules14072656
Received: 29 June 2009 / Revised: 13 July 2009 / Accepted: 17 July 2009 / Published: 22 July 2009
Cited by 19 | PDF Full-text (323 KB) | HTML Full-text | XML Full-text
Abstract
Theoretical calculations for some structural and electronic properties of the azide moiety in the nucleoside reverse transcriptase (RT) inhibitor 3¢-azido-3¢-deoxythymidine (AZT) are reported. These properties, which include geometrical properties in three dimensional space, Hirshfeld charges, electrostatic potential (MEP), vibrational frequencies, and core [...] Read more.
Theoretical calculations for some structural and electronic properties of the azide moiety in the nucleoside reverse transcriptase (RT) inhibitor 3¢-azido-3¢-deoxythymidine (AZT) are reported. These properties, which include geometrical properties in three dimensional space, Hirshfeld charges, electrostatic potential (MEP), vibrational frequencies, and core and valence ionization spectra, are employed to study how the azide group is affected by the presence of a larger fragment. For this purpose, two small but important organic azides, hydrazoic acid and methyl azide, are also considered. The general features of trans Cs configuration for RNNN fragments[1] is distorted in the large AZT bio-molecule. Hirshfeld charge analysis shows charges are reallocated more evenly on azide when the donor group R is not a single atom. Infrared and photoelectron spectra reveal different aspects of the compounds. In conclusion, the electronic structural properties of the compounds depend on the specific property, the local structure and chemical environment of a species. Full article
(This article belongs to the Special Issue Macromolecules: Chemistry, Medicinal and Functional Materials)
Open AccessArticle Mechanism of Introduction of Exogenous Genes into Cultured Cells Using DEAE-Dextran-MMA Graft Copolymer as Non-Viral Gene Carrier
Molecules 2009, 14(7), 2669-2683; doi:10.3390/molecules14072669
Received: 30 June 2009 / Revised: 8 July 2009 / Accepted: 15 July 2009 / Published: 23 July 2009
Cited by 12 | PDF Full-text (266 KB) | HTML Full-text | XML Full-text
Abstract
Comparative investigations were carried out regarding the efficiency of introduction of exogenous genes into cultured cells using a cationic polysaccharide DEAE-dextran-MMA (methyl methacrylate ester) graft copolymer (2-diethylaminoethyl-dextran-methyl methacrylate graft copolymer; DDMC) as a nonviral carrier for gene introduction. The results confirmed that [...] Read more.
Comparative investigations were carried out regarding the efficiency of introduction of exogenous genes into cultured cells using a cationic polysaccharide DEAE-dextran-MMA (methyl methacrylate ester) graft copolymer (2-diethylaminoethyl-dextran-methyl methacrylate graft copolymer; DDMC) as a nonviral carrier for gene introduction. The results confirmed that the gene introduction efficiency was improved with DDMC relative to DEAE-dextran. Comparative investigations were carried out using various concentrations of DDMC and DNA in the introduction of DNA encoding luciferase (pGL3 control vector; Promega) into COS-7 cells derived from African green monkey kidney cells. The complex formation reaction is thought to be directly proportional to the transformation rate, but the complex formation reaction between DDMC and DNA is significantly influenced by hydrophobic bonding strength along with hydrogen bonding strength and Coulomb forces due to the hydrophobicity of the grafted MMA sections. It is thought that the reaction is a Michaelis-Menten type complex formation reaction described by the following equation: Complex amount = K1 (DNA concentration)(DDMC concentration). In support of this equation, it was confirmed that the amount of formed complex was proportional to the RLU value. Full article
(This article belongs to the Special Issue Macromolecules: Chemistry, Medicinal and Functional Materials)

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Open AccessReview Pentavalent Antimonials: New Perspectives for Old Drugs
Molecules 2009, 14(7), 2317-2336; doi:10.3390/molecules14072317
Received: 23 April 2009 / Revised: 15 June 2009 / Accepted: 22 June 2009 / Published: 30 June 2009
Cited by 122 | PDF Full-text (537 KB) | HTML Full-text | XML Full-text
Abstract
Pentavalent antimonials, including meglumine antimoniate and sodium stibogluconate, have been used for more than half a century in the therapy of the parasitic disease leishmaniasis. Even though antimonials are still the first-line drugs, they exhibit several limitations, including severe side effects, the [...] Read more.
Pentavalent antimonials, including meglumine antimoniate and sodium stibogluconate, have been used for more than half a century in the therapy of the parasitic disease leishmaniasis. Even though antimonials are still the first-line drugs, they exhibit several limitations, including severe side effects, the need for daily parenteral administration and drug resistance. The molecular structure of antimonials, their metabolism and mechanism of action are still being investigated. Some recent studies suggest that pentavalent antimony acts as a prodrug that is converted to active and more toxic trivalent antimony. Other works support the direct involvement of pentavalent antimony. Recent data suggest that the biomolecules, thiols and ribonucleosides, may mediate the actions of these drugs. This review will summarize the progress to date on the chemistry and biochemistry of pentavalent antimony. It will also present the most recent works being done to improve antimonial chemotherapy. These works include the development of simple synthetic methods for pentavalent antimonials, liposome-based formulations for targeting the Leishmania parasites responsible for visceral leishmaniasis and cyclodextrin-based formulations to promote the oral delivery of antimony. Full article
(This article belongs to the Special Issue Neglected Diseases: Medicinal Chemistry and Natural Product Chemistry)
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Open AccessReview Selenium and the Methionine Sulfoxide Reductase System
Molecules 2009, 14(7), 2337-2344; doi:10.3390/molecules14072337
Received: 12 June 2009 / Revised: 26 June 2009 / Accepted: 30 June 2009 / Published: 1 July 2009
Cited by 7 | PDF Full-text (54 KB) | HTML Full-text | XML Full-text
Abstract
Selenium is a chemical element participating in the synthesis of selenocysteine residues that play a pivotal role in the enzymatic activity efficiency of selenoproteines. The methionine sulfoxide reductase (Msr) system that reduces methionine sulfoxide (MetO) to methionine comprises the selenoprotein MsrB (MsrB1) [...] Read more.
Selenium is a chemical element participating in the synthesis of selenocysteine residues that play a pivotal role in the enzymatic activity efficiency of selenoproteines. The methionine sulfoxide reductase (Msr) system that reduces methionine sulfoxide (MetO) to methionine comprises the selenoprotein MsrB (MsrB1) and the non-selenoprotein MsrA, which reduce the R- and the S- forms of MetO, respectively. The effects of a selenium deficient (SD) diet, which was administrated to wild type (WT) and MsrA knockout mice (MsrA-/-), on the expression and function of Msr-related proteins are examined and discussed. Additionally, new data about the levels of selenium in brain, liver, and kidneys of WT and MsrA-/- mice are presented and discussed. Full article
(This article belongs to the Special Issue Selenium and Tellurium Chemistry)
Open AccessReview Steroidal Lactones from Withania somnifera, an Ancient Plant for Novel Medicine
Molecules 2009, 14(7), 2373-2393; doi:10.3390/molecules14072373
Received: 27 May 2009 / Revised: 23 June 2009 / Accepted: 2 July 2009 / Published: 3 July 2009
Cited by 112 | PDF Full-text (342 KB) | HTML Full-text | XML Full-text
Abstract
Withania somnifera, commonly known as Ashwagandha, is an important medicinal plant that has been used in Ayurvedic and indigenous medicine for over 3,000 years. In view of its varied therapeutic potential, it has also been the subject of considerable modern scientific attention. [...] Read more.
Withania somnifera, commonly known as Ashwagandha, is an important medicinal plant that has been used in Ayurvedic and indigenous medicine for over 3,000 years. In view of its varied therapeutic potential, it has also been the subject of considerable modern scientific attention. The major chemical constituents of the Withania genus, the withanolides, are a group of naturally occurring C28-steroidal lactone triterpenoids built on an intact or rearranged ergostane framework, in which C-22 and C-26 are appropriately oxidized to form a six-membered lactone ring. In recent years, numerous pharmacological investigations have been carried out into the components of W. somnifera extracts. We present here an overview of the chemical structures of triterpenoid components and their biological activity, focusing on two novel activities, tumor inhibition and antiangiogenic properties of withaferin A and the effects of withanolide A on Alzheimer's disease. The most recent attempts in biotechnological production of withanolides are also discussed. Full article
(This article belongs to the Special Issue Triterpenes and Triterpenoids)
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Open AccessReview Bacterial Extracellular Polysaccharides Involved in Biofilm Formation
Molecules 2009, 14(7), 2535-2554; doi:10.3390/molecules14072535
Received: 18 May 2009 / Revised: 26 June 2009 / Accepted: 1 July 2009 / Published: 13 July 2009
Cited by 236 | PDF Full-text (333 KB) | HTML Full-text | XML Full-text
Abstract
Extracellular polymeric substances (EPS) produced by microorganisms are a complex mixture of biopolymers primarily consisting of polysaccharides, as well as proteins, nucleic acids, lipids and humic substances. EPS make up the intercellular space of microbial aggregates and form the structure and architecture [...] Read more.
Extracellular polymeric substances (EPS) produced by microorganisms are a complex mixture of biopolymers primarily consisting of polysaccharides, as well as proteins, nucleic acids, lipids and humic substances. EPS make up the intercellular space of microbial aggregates and form the structure and architecture of the biofilm matrix. The key functions of EPS comprise the mediation of the initial attachment of cells to different substrata and protection against environmental stress and dehydration. The aim of this review is to present a summary of the current status of the research into the role of EPS in bacterial attachment followed by biofilm formation. The latter has a profound impact on an array of biomedical, biotechnology and industrial fields including pharmaceutical and surgical applications, food engineering, bioremediation and biohydrometallurgy. The diverse structural variations of EPS produced by bacteria of different taxonomic lineages, together with examples of biotechnological applications, are discussed. Finally, a range of novel techniques that can be used in studies involving biofilm-specific polysaccharides is discussed. Full article
(This article belongs to the Special Issue Macromolecules: Chemistry, Medicinal and Functional Materials)
Open AccessReview Polymeric Plant-derived Excipients in Drug Delivery
Molecules 2009, 14(7), 2602-2620; doi:10.3390/molecules14072602
Received: 22 June 2009 / Revised: 1 July 2009 / Accepted: 6 July 2009 / Published: 16 July 2009
Cited by 97 | PDF Full-text (324 KB) | HTML Full-text | XML Full-text
Abstract
Drug dosage forms contain many components in addition to the active pharmaceutical ingredient(s) to assist in the manufacturing process as well as to optimise drug delivery. Due to advances in drug delivery technology, excipients are currently included in novel dosage forms to [...] Read more.
Drug dosage forms contain many components in addition to the active pharmaceutical ingredient(s) to assist in the manufacturing process as well as to optimise drug delivery. Due to advances in drug delivery technology, excipients are currently included in novel dosage forms to fulfil specific functions and in some cases they directly or indirectly influence the extent and/or rate of drug release and absorption. Since plant polysaccharides comply with many requirements expected of pharmaceutical excipients such as non-toxicity, stability, availability and renewability they are extensively investigated for use in the development of solid oral dosage forms. Furthermore, polysaccharides with varying physicochemical properties can be extracted from plants at relatively low cost and can be chemically modified to suit specific needs. As an example, many polysaccharide-rich plant materials are successfully used as matrix formers in modified release dosage forms. Some natural polysaccharides have even shown environmental-responsive gelation characteristics with the potential to control drug release according to specific therapeutic needs. This review discusses some of the most important plant-derived polymeric compounds that are used or investigated as excipients in drug delivery systems. Full article
(This article belongs to the Special Issue Macromolecules Applied to Pharmaceutics)

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