Next Issue
Volume 15, June
Previous Issue
Volume 15, April
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
7.4
4.2
Journals
Molecules
Volume 15
Issue 5
molecules-logo

Journal Menu

► Journal Menu

Journal Browser

► Journal Browser
share announcement

Molecules, Volume 15, Issue 5 (May 2010) – 57 articles , Pages 2935-3774

  • Issues are regarded as officially published after their release is announced to the table of contents alert mailing list.
  • You may sign up for e-mail alerts to receive table of contents of newly released issues.
  • PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Reader to open them.
Order results
Result details
Section
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
248 KiB  
Review
Photochemical Transformations of Tetrazole Derivatives: Applications in Organic Synthesis
by Luís Miguel Teodoro Frija, Amin Ismael and Maria Lurdes Santos Cristiano
Molecules 2010, 15(5), 3757-3774; https://doi.org/10.3390/molecules15053757 - 25 May 2010
Cited by 111 | Viewed by 14822
Abstract
Tetrazoles remain a challenge to photochemists. Photolysis leads to cleavage of the tetrazolyl ring, may involve various photodegradation pathways and may produce a diversity of photoproducts, depending on the structure and conformational flexibility of the substituents and the possibility of tautomerism. If the [...] Read more.
Tetrazoles remain a challenge to photochemists. Photolysis leads to cleavage of the tetrazolyl ring, may involve various photodegradation pathways and may produce a diversity of photoproducts, depending on the structure and conformational flexibility of the substituents and the possibility of tautomerism. If the photochemistry of tetrazoles is considered within the frame of synthetic applications the subject is even more challenging, since the ultimate goal is to achieve selectivity and high yield. In addition, the photoproducts must remain stable and allow isolation or trapping, in order to be used in other reactions. This review summarises the photochemical transformations of tetrazole derivatives that can be used as effective synthetic routes to other compounds. Full article
(This article belongs to the Special Issue Photochemistry in Organic Synthesis)
►▼ Show Figures

Figure 1

199 KiB  
Article
Oak (Quercus frainetto Ten.) Honeydew Honey—Approach to Screening of Volatile Organic Composition and Antioxidant Capacity (DPPH and FRAP Assay)
by Igor Jerković and Zvonimir Marijanović
Molecules 2010, 15(5), 3744-3756; https://doi.org/10.3390/molecules15053744 - 25 May 2010
Cited by 49 | Viewed by 13207
Abstract
Two samples of oak honeydew honey were investigated. Headspace solid-phase microextraction (HS-SPME) combined with GC and GC/MS enabled identification of the most volatile organic headspace compounds being dominated by terpenes(mainly cis- and trans-linalool oxides). The volatile and less-volatile organic composition of [...] Read more.
Two samples of oak honeydew honey were investigated. Headspace solid-phase microextraction (HS-SPME) combined with GC and GC/MS enabled identification of the most volatile organic headspace compounds being dominated by terpenes(mainly cis- and trans-linalool oxides). The volatile and less-volatile organic composition of the samples was obtained by ultrasonic assisted extraction (USE) with two solvents (1:2 (v/v) pentane -diethyl ether mixture and dichloromethane) followed by GC and GC/MS analysis. Shikimic pathway derivatives are of particular interest with respect to the botanical origin of honey and the most abundant was phenylacetic acid (up to 16.4%). Antiradical activity (DPPH assay) of the honeydew samples was 4.5 and 5.1 mmol TEAC/kg. Ultrasonic solvent extracts showed several dozen times higher antiradical capacity in comparison to the honeydew. Antioxidant capacity (FRAP assay) of honeydew samples was 4.8 and 16.1 mmol Fe2+/kg, while the solvent mixture extracts showed antioxidant activity of 374.5 and 955.9 Fe2+/kg, respectively, and the dichloromethane extracts 127.3 and 101.5 mmol Fe2+/kg. Full article
(This article belongs to the Special Issue Antioxidants)
►▼ Show Figures

Figure 1

183 KiB  
Article
Microwave Synthesis, Basic Spectral and Biological Evaluation of Some Copper (II) Mesoporphyrinic Complexes
by Rica Boscencu, Mihaela Ilie, Radu Socoteanu, Anabela Sousa Oliveira, Carolina Constantin, Monica Neagu, Gina Manda and Luis Filipe Vieira Ferreira
Molecules 2010, 15(5), 3731-3743; https://doi.org/10.3390/molecules15053731 - 25 May 2010
Cited by 27 | Viewed by 8703
Abstract
Cu(II) complexes with asymmetrical and symmetrical porphyrinic ligands were synthesized with superior yields using microwave irradiation. The paper presents the synthesis of 5-(3-hydroxyphenyl)-10,15,20-tris-(4-carboxymethylphenyl)-21,23-Cu(II)-porphine in comparison to its symmetrical complex 5,10,15,20-meso-tetrakis-(4-carboxy-methylphenyl)-21,23-Cu(II) porphine. The two compounds were characterized by FT-IR, UV–Vis and EPR [...] Read more.
Cu(II) complexes with asymmetrical and symmetrical porphyrinic ligands were synthesized with superior yields using microwave irradiation. The paper presents the synthesis of 5-(3-hydroxyphenyl)-10,15,20-tris-(4-carboxymethylphenyl)-21,23-Cu(II)-porphine in comparison to its symmetrical complex 5,10,15,20-meso-tetrakis-(4-carboxy-methylphenyl)-21,23-Cu(II) porphine. The two compounds were characterized by FT-IR, UV–Vis and EPR spectroscopy, which fully confirmed the structures. The spectral molecular absorption properties of the porphyrinic complexes were studied in organic solvents (methanol, ethanol, iso-propanol, dimethyl sulfoxide, dimethylformamide and methylene chloride), and the influence of the solvent polarity on the absorbance maxima is described. In order to establish their future potential in biomedical applications preliminary toxicological studies consisting of viability and proliferation of standard tumor cell lines (MCF7 and B16) testing was performed. The obtained results indicate a low toxicity for both compounds and further recommends them for testing in light activation protocols. Full article
►▼ Show Figures

Graphical abstract

440 KiB  
Review
Recent Advances in the Synthesis of Ammonium-Based Rotaxanes
by Dominic Thibeault and Jean-François Morin
Molecules 2010, 15(5), 3709-3730; https://doi.org/10.3390/molecules15053709 - 25 May 2010
Cited by 51 | Viewed by 15978
Abstract
The number of synthetic methods enabling the preparation of ammonium-based rotaxanes has increased very rapidly in the past ten years. The challenge in the synthesis of rotaxanes results from the rather weak interactions between the ammonium-containing rod and the crown ether macrocycle in [...] Read more.
The number of synthetic methods enabling the preparation of ammonium-based rotaxanes has increased very rapidly in the past ten years. The challenge in the synthesis of rotaxanes results from the rather weak interactions between the ammonium-containing rod and the crown ether macrocycle in the pseudorotaxane structure that rely mostly on O•H hydrogen bonds. Indeed, no strong base or polar solvent that could break up H-bonding can be used during the formation of rotaxanes because the two components will separate as two distinct entities. Moreover, most of the reactions have to be performed at room temperature to favor the formation of pseudorotaxane in solution. These non-trivial prerequisites have been taken into account to develop efficient reaction conditions for the preparation of rotaxanes and those are described in detail along this review. Full article
(This article belongs to the Special Issue Supramolecular Assembly)
►▼ Show Figures

Figure 1

474 KiB  
Article
Optimization of Alkaline Extraction of Polysaccharides from Ganoderma lucidum and Their Effect on Immune Function in Mice
by Sheng-Quan Huang, Jin-Wei Li, Zhou Wang, Hua-Xin Pan, Jiang-Xu Chen and Zheng-Xiang Ning
Molecules 2010, 15(5), 3694-3708; https://doi.org/10.3390/molecules15053694 - 25 May 2010
Cited by 65 | Viewed by 13229
Abstract
Response surface methodology was employed to optimize the conditions for alkaline extraction of polysaccharides from Ganoderma lucidum. The results indicated that the optimum conditions were an extraction temperature of 60.1 ºC, an extraction time of 77.3 min, a sodium hydroxide (NaOH) concentration [...] Read more.
Response surface methodology was employed to optimize the conditions for alkaline extraction of polysaccharides from Ganoderma lucidum. The results indicated that the optimum conditions were an extraction temperature of 60.1 ºC, an extraction time of 77.3 min, a sodium hydroxide (NaOH) concentration of 5.1% and a substrate/liquid ratio of 1:21.4. Immunological assays results have shown that the alkaline soluble polysaccharides have no noticeable effects on monocyte phagocytosis and immune organ (spleen, thymus) weight of of immunocompromised mice at the tested dosages. However, they could restore delayed type hypersensitivity reaction to dinitrofluorobenzene (DFNB), hemolysis antibody levels at the three doses applied, and improve the natural killer cell activity at the high-dose and medium dose. Full article
►▼ Show Figures

Figure 1

186 KiB  
Article
Determination of Essential Oil Composition from Osmanthus fragrans Tea by GC-MS Combined with a Chemometric Resolution Method
by Chun-Di Hu, Yi-Zeng Liang, Fang-Qiu Guo, Xiao-Ru Li and Wei-Ping Wang
Molecules 2010, 15(5), 3683-3693; https://doi.org/10.3390/molecules15053683 - 19 May 2010
Cited by 34 | Viewed by 13222
Abstract
The essential oils of the Osmanthus fragrans tea (OFT), Osmanthus fragrans (OF) and green tea (GT) had been extracted by steam distillation and analyzed by gas chromatography-mass spectrometry (GC-MS) with the help of heuristic evolving latent projections (HELP), an effective chemometric resolution method [...] Read more.
The essential oils of the Osmanthus fragrans tea (OFT), Osmanthus fragrans (OF) and green tea (GT) had been extracted by steam distillation and analyzed by gas chromatography-mass spectrometry (GC-MS) with the help of heuristic evolving latent projections (HELP), an effective chemometric resolution method (CRM). The overlapping peak clusters were resolved into pure chromatograms and pure mass spectra with HELP. The qualitative analysis was performed by similarity searches in the National Institute of Standards and Technology (NIST) mass spectra database with the obtained pure mass spectrum of each component. Identification of some compounds was also assisted by comparison of temperature-programmed retention indices (PTRI) with authentic standards included in our own laboratory database under construction. The quantitative results were obtained by overall volume integration (OVI) method. A total of 67, 73 and 53 components in essential oils of the OFT, OF and GT were identified, accounting for 90.83%, 93.65% and 89.97% total contents of the essential oil of OFT, OF and GT, respectively. Full article
►▼ Show Figures

Figure 1

486 KiB  
Article
Synthesis and Characterization of Polycarbonates by Melt Phase Interchange Reactions of Alkylene and Arylene Diacetates with Alkylene and Arylene Diphenyl Dicarbonates
by Bassam A. Sweileh, Yusuf M. Al-Hiari, Mohammad H. Kailani and Hani A. Mohammad
Molecules 2010, 15(5), 3661-3682; https://doi.org/10.3390/molecules15053661 - 18 May 2010
Cited by 36 | Viewed by 12879
Abstract
This work presents a new synthetic approach to aromatic and aliphatic polycarbonates by melt polycondensation of bisphenol A diacetates with alkylene- and arylenediphenyl dicarbonates. The diphenyl dicarbonates were prepared from phenyl chloroformate and the corresponding dihydroxy compounds. The process involved a precondensation step [...] Read more.
This work presents a new synthetic approach to aromatic and aliphatic polycarbonates by melt polycondensation of bisphenol A diacetates with alkylene- and arylenediphenyl dicarbonates. The diphenyl dicarbonates were prepared from phenyl chloroformate and the corresponding dihydroxy compounds. The process involved a precondensation step under a slow stream of dry argon with the elimination of phenyl acetate, followed by melt polycondensation at high temperature and under vacuum. The potential of this reaction is demonstrated by the successful synthesis of a series of aromatic-aromatic and aromatic-aliphatic polycarbonates having inherent viscosities from 0.19 to 0.43 dL/g. Thus low to intermediate molecular mass polymers were obtained. The 13C-NMR spectra of the carbon of the carbonate group showed that the formed polycarbonates contain partial random sequence distribution of monomer residues in their chains. The polycarbonates were characterized by inherent viscosity, FTIR, 1H-NMR and 13C-NMR spectroscopy. The glass transition temperatures, measured by DSC, of the polycarbonates were in the range 13–108 ºC. The thermogravimetric curves of showed that these polymers have good thermal stability up to 250 ºC. The present approach may open the door for novel polycarbonates containing other organic functional groups. Full article
►▼ Show Figures

Figure 1

720 KiB  
Article
Enantioselectivity Induced by Oxazaborolidine Supported on Mesoporous Silica or by Its Analog in Homogeneous Phase
by Jeremy H. Yune, Françoise Quignard and Karine Molvinger
Molecules 2010, 15(5), 3643-3660; https://doi.org/10.3390/molecules15053643 - 18 May 2010
Cited by 3 | Viewed by 8861
Abstract
The impact of immobilization of oxazaborolidines supported on silica via different substituents on the boron and nitrogen atoms is evaluated in the enantioselective reduction of acetophenone. The performances of the homogeneous analog oxazaborolidines and silica supported-ones are compared by varying different parameters. This [...] Read more.
The impact of immobilization of oxazaborolidines supported on silica via different substituents on the boron and nitrogen atoms is evaluated in the enantioselective reduction of acetophenone. The performances of the homogeneous analog oxazaborolidines and silica supported-ones are compared by varying different parameters. This article deals with the synthesis, characterization and catalytic evaluation of silica-supported oxazaborolidines, their recycling capabilities and regeneration limitations. Full article
(This article belongs to the Special Issue Heterogeneous Catalysis)
►▼ Show Figures

Figure 1

326 KiB  
Article
Synthesis and Effect on Human HepG2 Cells of 1,2-bis- (2-Methylallyl)disulfane
by Chunxiao Ji, Fenglian Ren, Jun Dai and Ming Xu
Molecules 2010, 15(5), 3634-3642; https://doi.org/10.3390/molecules15053634 - 18 May 2010
Viewed by 6490
Abstract
1,2-bis(2-methylallyl)disulfane was synthesized from sodium sulfide and 3-chloro-2-methylpropylene. The structure of the target product was confirmed by GC-MS, 1H-NMR and elemental analysis. Cell viability assay, flow-cytometric analysis and protein expression results showed that 1,2-bis(2-methylallyl)disulfane could significantly inhibit the proliferation, and induce the apoptosis [...] Read more.
1,2-bis(2-methylallyl)disulfane was synthesized from sodium sulfide and 3-chloro-2-methylpropylene. The structure of the target product was confirmed by GC-MS, 1H-NMR and elemental analysis. Cell viability assay, flow-cytometric analysis and protein expression results showed that 1,2-bis(2-methylallyl)disulfane could significantly inhibit the proliferation, and induce the apoptosis of human HepG2 cells. Full article
►▼ Show Figures

Figure 1

441 KiB  
Article
Synthesis and Spectrosopic Identification of Hybrid 3-(Triethoxysilyl)propylamine Phosphine Ruthenium(II) Complexes
by Ismail Warad, Saud Al-Resayes, Zeid Al-Othman, Salem S. Al-Deyab and El-Refaie Kenawy
Molecules 2010, 15(5), 3618-3633; https://doi.org/10.3390/molecules15053618 - 17 May 2010
Cited by 6 | Viewed by 11193
Abstract
An investigation into the potential ruthenium(II) 1-3 complexes of type [RuCl2(P)2(N)2] using triphenylphosphine and 1,3-bis-diphenylphosphinepropane and 3-(triethoxysilyl)propylamine has been carried out at room temperature in dichloromethane under an inert atmosphere. The structural behaviors of the [...] Read more.
An investigation into the potential ruthenium(II) 1-3 complexes of type [RuCl2(P)2(N)2] using triphenylphosphine and 1,3-bis-diphenylphosphinepropane and 3-(triethoxysilyl)propylamine has been carried out at room temperature in dichloromethane under an inert atmosphere. The structural behaviors of the phosphine ligands in the desired complexes during synthesis were monitored by 31P{1H}-NMR. The structure of complexes 1-3 described herein has been deduced from elemental analyses, infrared, FAB-MS and 1H-, 13C- and 31P-NMR spectroscopy. Xerogels X1-X3 were synthesized by simple sol-gel process of complexes 1-3 using tetraethoxysilane as co-condensation agent in methanol/THF/water solution. Due to their lack of solubility, the structures of X1-X3 were determined by solid state 13C-, 29Si- and 31P-NMR spectroscopy, infrared spectroscopy and EXAFS. Full article
►▼ Show Figures

Figure 1

413 KiB  
Article
The Reaction of Cyanoacetylhydrazine with ω-Bromo(4-methyl)acetophenone: Synthesis of Heterocyclic Derivatives with Antitumor Activity
by Rafat M. Mohareb and Abeer A. Mohamed
Molecules 2010, 15(5), 3602-3617; https://doi.org/10.3390/molecules15053602 - 17 May 2010
Cited by 25 | Viewed by 10783
Abstract
New approaches for the synthesis of hydrazide-hydrazone derivatives were demonstrated as well as some heterocyclizations of such derivatives to afford 1,3,4-triazine, pyridine and 1,3,4-oxadiazine derivatives. The antitumor evaluation of the newly synthesized products against three cancer cell lines, namely breast adenocarcinoma (MCF-7), non-small [...] Read more.
New approaches for the synthesis of hydrazide-hydrazone derivatives were demonstrated as well as some heterocyclizations of such derivatives to afford 1,3,4-triazine, pyridine and 1,3,4-oxadiazine derivatives. The antitumor evaluation of the newly synthesized products against three cancer cell lines, namely breast adenocarcinoma (MCF-7), non-small cell lung cancer (NCI-H460) and CNS cancer (SF-268) were recorded. Most of the synthesized compounds showed high inhibitory effects. Full article
►▼ Show Figures

Figure 1

198 KiB  
Article
Microwave-Assisted One-Pot Synthesis of Pyrazolone Derivatives under Solvent-Free Conditions
by Ruoqun Ma, Jin Zhu, Jie Liu, Lili Chen, Xu Shen, Hualiang Jiang and Jian Li
Molecules 2010, 15(5), 3593-3601; https://doi.org/10.3390/molecules15053593 - 17 May 2010
Cited by 48 | Viewed by 10796
Abstract
An efficient one-pot method to generate structurally diverse and medicinally interesting pyrazolone derivatives in good to excellent yields of 51–98% under microwave irradiation and solvent-free conditions has been developed. Full article
►▼ Show Figures

Figure 1

587 KiB  
Article
Effects of Andrographis paniculata and Orthosiphon stamineus Extracts on the Glucuronidation of 4-Methylumbelliferone in Human UGT Isoforms
by Sabariah Ismail, Nur Aziah Hanapi, Mohd Rohaimi Ab Halim, Verawan Uchaipichat and Peter I. Mackenzie
Molecules 2010, 15(5), 3578-3592; https://doi.org/10.3390/molecules15053578 - 14 May 2010
Cited by 15 | Viewed by 8807
Abstract
The effects of Andrographis paniculata and Orthosiphon stamineus extracts on the in vitro glucuronidation of 4-methylumbelliferone (4MU) by recombinant human UGTs, UGT1A1, UGT1A3, UGT1A6, UGT1A7, UGT1A8, UGT1A10, UGT2B7 and UGT2B15 were determined. The potential inhibitory effects of both of the extracts on the [...] Read more.
The effects of Andrographis paniculata and Orthosiphon stamineus extracts on the in vitro glucuronidation of 4-methylumbelliferone (4MU) by recombinant human UGTs, UGT1A1, UGT1A3, UGT1A6, UGT1A7, UGT1A8, UGT1A10, UGT2B7 and UGT2B15 were determined. The potential inhibitory effects of both of the extracts on the activity of each of the UGT isoforms were investigated using 4MU as the substrate. Incubations contained UDP-glucuronic acid (UDPGA) as the cofactor, MgCl2, cell lysate of respective isoform, and 4MU at the approximate apparent Km or S50 value of each isoform. Final concentrations of Andrographis paniculata and Orthosiphon stamineus extracts used were 0.025, 0.25, 2.5, 25 and 50 μg/mL and 0.01, 0.10, 1.0, 10 and 50 μg/mL respectively. Both extracts variably inhibited the activity of most of the isoforms in a concentration dependent manner. Andrographis paniculata extract was the better inhibitor of all the isoforms studied (IC50 1.70 μg/mL for UGT1A3, 2.57 μg/mL for UGT1A8, 2.82 μg/mL for UGT2B7, 5.00 μg/mL for UGT1A1, 5.66 μg/mL for UGT1A6, 9.88 μg/mL for UGT1A7 and 15.66 μg/mL for UGT1A10). Both extracts showed less than 70% inhibition of UGT2B15, so the IC50 values were >50μg/mL. The inhibition of human UGTs by Andrographis paniculata and Orthosiphon stamineus extracts in vitro suggests a potential for drug-herbal extract interactions in the therapeutic setting. Full article
►▼ Show Figures

Figure 1

427 KiB  
Article
Phenolic Extracts from Acacia mangium Bark and Their Antioxidant Activities
by Liangliang Zhang, Jiahong Chen, Yongmei Wang, Dongmei Wu and Man Xu
Molecules 2010, 15(5), 3567-3577; https://doi.org/10.3390/molecules15053567 - 14 May 2010
Cited by 40 | Viewed by 14421
Abstract
Phenolic compounds are present at very high concentrations in the bark of Acacia mangium. These compounds are known to have strong antioxidant activity and thus different beneficial effects on human health. Phenolic compounds in bark of A. mangium were extracted and [...] Read more.
Phenolic compounds are present at very high concentrations in the bark of Acacia mangium. These compounds are known to have strong antioxidant activity and thus different beneficial effects on human health. Phenolic compounds in bark of A. mangium were extracted and their antioxidant activities were investigated using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical-scavenging and ferric-reducing antioxidant power (FRAP) assays. A central composite design has been employed to optimize the experimental conditions for a high total phenolic content and antioxidant activity. The desirability function approach has been employed to simultaneously optimize the three responses: total phenols, antiradical activity and FRAP. An extraction time of 90 min, liquid-solid ratio of 5, and temperature of 50 °C was predicted for the optimum experimental conditions using the desirability function. A significant linear relationship between antioxidant potency, antiradical activity and the content of phenolic compounds of bark extracts was observed. The structures of condensed tannins isolated from A. mangium were characterized by MALDI-TOF MS analyses. Condensed tannin oligomers from A. mangium were shown to be heterogeneous mixtures consisting of procyanidin and prodelphinidin structural units with polymerization degrees up to 9. Full article
(This article belongs to the Special Issue Phenolics and Polyphenolics)
►▼ Show Figures

Figure 1

321 KiB  
Article
Characterization of Aromatase Binding Agents from the Dichloromethane Extract of Corydalis yanhusuo Using Ultrafiltration and Liquid Chromatography Tandem Mass Spectrometry
by Jing Shi, Xiaoyu Zhang, Zhongjun Ma, Min Zhang and Fang Sun
Molecules 2010, 15(5), 3556-3566; https://doi.org/10.3390/molecules15053556 - 14 May 2010
Cited by 22 | Viewed by 10407
Abstract
Aromatase represents an important target for the treatment of hormone-dependent breast cancer. In the present study, nine alkaloids from the dichloromethane extract of Corydalis yanhusuo were identified by liquid chromatography tandem mass spectrometry (LC-MS/MS) and tested for their aromatase binding activities using an [...] Read more.
Aromatase represents an important target for the treatment of hormone-dependent breast cancer. In the present study, nine alkaloids from the dichloromethane extract of Corydalis yanhusuo were identified by liquid chromatography tandem mass spectrometry (LC-MS/MS) and tested for their aromatase binding activities using an ultrafiltration LC-MS method by investigating the differences of peak areas of compounds before and after incubations with aromatase. It was demonstrated that the quaternary protoberberine alkaloids and the tertiary protoberberine alkaloids exhibited potent aromatase binding activities. The quaternary ammonium group and the methyl group at C-13 position of tertiary protoberberine alkaloids might be necessary for the activity. The findings should provide guidance for the discovery of potential aromatase inhibitors from natural products. Full article
►▼ Show Figures

Graphical abstract

5057 KiB  
Review
Neuroprotective Herbs and Foods from Different Traditional Medicines and Diets
by Marcello Iriti, Sara Vitalini, Gelsomina Fico and Franco Faoro
Molecules 2010, 15(5), 3517-3555; https://doi.org/10.3390/molecules15053517 - 14 May 2010
Cited by 133 | Viewed by 20296
Abstract
Plant secondary metabolites include an array of bioactive constituents form both medicinal and food plants able to improve human health. The exposure to these phytochemicals, including phenylpropanoids, isoprenoids and alkaloids, through correct dietary habits, may promote health benefits, protecting against the chronic degenerative [...] Read more.
Plant secondary metabolites include an array of bioactive constituents form both medicinal and food plants able to improve human health. The exposure to these phytochemicals, including phenylpropanoids, isoprenoids and alkaloids, through correct dietary habits, may promote health benefits, protecting against the chronic degenerative disorders mainly seen in Western industrialized countries, such as cancer, cardiovascular and neurodegenerative diseases. In this review, we briefly deal with some plant foods and herbs of traditional medicines and diets, focusing on their neuroprotective active components. Because oxidative stress and neuroinflammation resulting from neuroglial activation, at the level of neurons, microglial cells and astrocytes, are key factors in the etiopathogenesis of both neurodegenerative and neurological diseases, emphasis will be placed on the antioxidant and anti-inflammatory activity exerted by specific molecules present in food plants or in remedies prescribed by herbal medicines. Full article
(This article belongs to the Special Issue Neuroprotective Strategies)
►▼ Show Figures

Figure 1

631 KiB  
Article
Antifungal Effect of (+)-Pinoresinol Isolated from Sambucus williamsii
by Bomi Hwang, Juneyoung Lee, Qing-He Liu, Eun-Rhan Woo and Dong Gun Lee
Molecules 2010, 15(5), 3507-3516; https://doi.org/10.3390/molecules15053507 - 14 May 2010
Cited by 57 | Viewed by 10795
Abstract
In this study, we investigated the antifungal activity and mechanism of action of (+)-pinoresinol, a biphenolic compound isolated from the herb Sambucus williamsii,used in traditional medicine. (+)-Pinoresinol displays potent antifungal properties without hemolytic effects on human erythrocytes. To understand the antifungal mechanism [...] Read more.
In this study, we investigated the antifungal activity and mechanism of action of (+)-pinoresinol, a biphenolic compound isolated from the herb Sambucus williamsii,used in traditional medicine. (+)-Pinoresinol displays potent antifungal properties without hemolytic effects on human erythrocytes. To understand the antifungal mechanism of (+)-pinoresinol, we conducted fluorescence experiments on the human pathogen Candida albicans. Fluorescence analysis using 1,6-diphenyl-1,3,5-hexatriene (DPH) indicated that the (+)-pinoresinol caused damage to the fungal plasma membrane. This result was confirmed by using rhodamine-labeled giant unilamellar vesicle (GUV) experiments. Therefore, the present study indicates that (+)-pinoresinol possesses fungicidal activities and therapeutic potential as an antifungal agent for the treatment of fungal infectious diseases in humans. Full article
(This article belongs to the Special Issue Anti-Infective Agents)
►▼ Show Figures

Figure 1

7642 KiB  
Review
Supramolecular Coordination Assemblies Constructed From Multifunctional Azole-Containing Carboxylic Acids
by Yuheng Deng, Hao Liu, Bo Yu and Min Yao
Molecules 2010, 15(5), 3478-3506; https://doi.org/10.3390/molecules15053478 - 12 May 2010
Cited by 25 | Viewed by 10927
Abstract
This paper provides a brief review of recent progress in the field of metal coordination polymers assembled from azole-containing carboxylic acids and gives a diagrammatic summary of the diversity of topological structures in the resulting infinite metal-organic coordination networks (MOCNs). Azole-containing carboxylic acids [...] Read more.
This paper provides a brief review of recent progress in the field of metal coordination polymers assembled from azole-containing carboxylic acids and gives a diagrammatic summary of the diversity of topological structures in the resulting infinite metal-organic coordination networks (MOCNs). Azole-containing carboxylic acids are a favorable kind of multifunctional ligand to construct various metal complexes with isolated complexes and one, two and three dimensional structures, whose isolated complexes are not the focus of this review. An insight into the topology patterns of the infinite coordination polymers is provided. Analyzed topologies are compared with documented topologies and catalogued by the nature of nodes and connectivity pattern. New topologies which are not available from current topology databases are described and demonstrated graphically. Full article
(This article belongs to the Special Issue Supramolecular Assembly)
►▼ Show Figures

Graphical abstract

195 KiB  
Article
Thionation of Some α,β-Unsaturated Steroidal Ketones
by Natalija M. Krstić, Mira S. Bjelaković, Milan M. Dabović and Vladimir D. Pavlović
Molecules 2010, 15(5), 3462-3477; https://doi.org/10.3390/molecules15053462 - 12 May 2010
Cited by 19 | Viewed by 9092
Abstract
The reactions of selected α,β-unsaturated steroidal ketones with Lawesson’s reagent (LR) in CH2Cl2 and toluene under the standard reaction conditions and with a combination of phosphorus pentasulfide with hexamethyldisiloxane (P4S10/HMDO) in 1,2-dichlorobenzene (ODCB) under microwave irradiation [...] Read more.
The reactions of selected α,β-unsaturated steroidal ketones with Lawesson’s reagent (LR) in CH2Cl2 and toluene under the standard reaction conditions and with a combination of phosphorus pentasulfide with hexamethyldisiloxane (P4S10/HMDO) in 1,2-dichlorobenzene (ODCB) under microwave irradiation were investigated and for this purpose several cholestane, androstane and pregnane carbonyl derivatives were chosen. Depending on the reagent and the solvent, 19 new sulfur containing compounds, including dithiones 4c and 4d, α,β-unsaturated 3-thiones 3a-e, dimer-sulfides 2a-e, 1,2,4-trithiolanes 5a-e and phosphonotrithioates 6b-e were synthesized. All newly prepared compounds were characterized by IR, 1H- and 13C-NMR spectroscopy and elemental analysis. Full article
►▼ Show Figures

Figure 1

1270 KiB  
Article
Carbon-Carbon Cross Coupling Reactions in Ionic Liquids Catalysed by Palladium Metal Nanoparticles
by Martin H. G. Prechtl, Jackson D. Scholten and Jairton Dupont
Molecules 2010, 15(5), 3441-3461; https://doi.org/10.3390/molecules15053441 - 12 May 2010
Cited by 148 | Viewed by 15660
Abstract
A brief summary of selected pioneering and mechanistic contributions in the field of carbon-carbon cross-coupling reactions with palladium nanoparticles (Pd-NPs) in ionic liquids (ILs) is presented. Five exemplary model systems using the Pd-NPs/ILs approach are presented: Heck, Suzuki, Stille, Sonogashira and Ullmann reactions [...] Read more.
A brief summary of selected pioneering and mechanistic contributions in the field of carbon-carbon cross-coupling reactions with palladium nanoparticles (Pd-NPs) in ionic liquids (ILs) is presented. Five exemplary model systems using the Pd-NPs/ILs approach are presented: Heck, Suzuki, Stille, Sonogashira and Ullmann reactions which all have in common the use of ionic liquids as reaction media and the use of palladium nanoparticles as reservoir for the catalytically active palladium species. Full article
(This article belongs to the Special Issue Nano-catalysts and Nano-technologies for Green Organic Synthesis)
►▼ Show Figures

Graphical abstract

453 KiB  
Article
Chiral Pt/ZrO2 Catalysts. Enantioselective Hydrogenation of 1-phenyl-1,2-propanedione
by Claudia Urbina, Cristian Campos, Gina Pecchi, Carmen Claver and Patricio Reyes
Molecules 2010, 15(5), 3428-3440; https://doi.org/10.3390/molecules15053428 - 12 May 2010
Cited by 5 | Viewed by 9294
Abstract
The enantioselective hydrogenation of 1-phenyl-1,2-propanedioneover Pt colloids stabilized with (R,S)-4,5-dihydro-4,5-diphenyl-2-(6-cyanopyridinyl)imidazoline (CI) supported on a meso-structured ZrO2 under a pressure of 40 bar of H2 at 298 K has been investigated. The metal loading in all catalysts was 1 [...] Read more.
The enantioselective hydrogenation of 1-phenyl-1,2-propanedioneover Pt colloids stabilized with (R,S)-4,5-dihydro-4,5-diphenyl-2-(6-cyanopyridinyl)imidazoline (CI) supported on a meso-structured ZrO2 under a pressure of 40 bar of H2 at 298 K has been investigated. The metal loading in all catalysts was 1 wt%. The effect of the amount of chiral modifier on the metal particle size and on the catalytic behavior was analyzed. It was found that as the CI/Pt molar ratio increases from 2.5 to 3.5 the Pt crystal size decreases from 3.0 to 1.8 nm. All catalysts were very active in the studied reaction, with the most active one being the catalyst with smaller Pt particles, whereas the selectivity is higher in those catalysts with larger chiral modified Pt metal particles. Full article
(This article belongs to the Special Issue Heterogeneous Catalysis)
►▼ Show Figures

Figure 1

115 KiB  
Communication
Characterization of the Volatile Substances and Aroma Components from Traditional Soypaste
by Yan Zhang, Xin Li, Chih-Kang Lo and Shun-Tang Guo
Molecules 2010, 15(5), 3421-3427; https://doi.org/10.3390/molecules15053421 - 11 May 2010
Cited by 44 | Viewed by 9606
Abstract
In this study, the flavor substances of soypaste were extracted by a simultaneous distillation method and identified by GC-MS. The characteristic aroma components of soypaste were determined by the GC-O technique and the FD value of the characteristic aroma components was determined by [...] Read more.
In this study, the flavor substances of soypaste were extracted by a simultaneous distillation method and identified by GC-MS. The characteristic aroma components of soypaste were determined by the GC-O technique and the FD value of the characteristic aroma components was determined by AEDA method. It could be inferred that the aroma of the soypaste should be attributed to the presence of heterocyclic compounds and organic acids, with the heterocyclic compounds playing a prominent role. Full article
►▼ Show Figures

Figure 1

1070 KiB  
Article
Standardization of Cassia spectabilis with Respect to Authenticity, Assay and Chemical Constituent Analysis
by Angeline Torey, Sreenivasan Sasidharan, Chen Yeng and Lachimanan Yoga Latha
Molecules 2010, 15(5), 3411-3420; https://doi.org/10.3390/molecules15053411 - 10 May 2010
Cited by 25 | Viewed by 8125
Abstract
Quality control standardizations of the various medicinal plants used in traditional medicine is becoming more important today in view of the commercialization of formulations based on these plants. An attempt at standardization of Cassia spectabilis leaf has been carried out with respect to [...] Read more.
Quality control standardizations of the various medicinal plants used in traditional medicine is becoming more important today in view of the commercialization of formulations based on these plants. An attempt at standardization of Cassia spectabilis leaf has been carried out with respect to authenticity, assay and chemical constituent analysis. The authentication involved many parameters, including gross morphology, microscopy of the leaves and functional group analysis by Fourier Transform Infrared (FTIR) spectroscopy. The assay part of standardization involved determination of the minimum inhibitory concentration (MIC) of the extract which could help assess the chemical effects and establish curative values. The MIC of the C. spectabilis leaf extracts was investigated using the Broth Dilution Method. The extracts showed a MIC value of 6.25 mg/mL, independent of the extraction time. The chemical constituent aspect of standardization involves quantification of the main chemical components in C. spectabilis. The GCMS method used for quantification of 2,4-(1H,3H)-pyrimidinedione in the extract was rapid, accurate, precise, linear (R2 = 0.8685), rugged and robust. Hence this method was suitable for quantification of this component in C. spectabilis. The standardization of C. spectabilis is needed to facilitate marketing of medicinal plants, with a view to promoting the export of valuable Malaysian Traditional Medicinal plants such as C. spectabilis. Full article
►▼ Show Figures

Figure 1

227 KiB  
Review
The Hydroarylation Reaction—Scope and Limitations
by Jan C. Namyslo, Jörg Storsberg, Jens Klinge, Christian Gärtner, Min-Liang Yao, Nuket Ocal and Dieter Eckhard Kaufmann
Molecules 2010, 15(5), 3402-3410; https://doi.org/10.3390/molecules15053402 - 10 May 2010
Cited by 39 | Viewed by 14333
Abstract
The synthetic potential of stereoselective, palladium-catalyzed hydro(het)arylation reactions of bi-, tri- and tetracyclic (hetero)alkenes in the presence of phospines and arsines as highly efficient ligands was studied. The mechanism of this reductive Heck reaction becomes more complex in the case of benzonorbornenes. Hydroarylation [...] Read more.
The synthetic potential of stereoselective, palladium-catalyzed hydro(het)arylation reactions of bi-, tri- and tetracyclic (hetero)alkenes in the presence of phospines and arsines as highly efficient ligands was studied. The mechanism of this reductive Heck reaction becomes more complex in the case of benzonorbornenes. Hydroarylation of diazabicyclo-[2.2.1]heptenes provides a stereoselective access to aryldiaminocyclopentanes. Electron-deficient arylpalladium complexes shift the reaction towards the product of a formal 1,2-hydrazidoarylation reaction of 1,3-cyclopentadiene by a stereoselective C-N cleavage. Due to steric reasons, rigid bicyclo[2.2.2]octenes react slower in hydroarylation reactions than the corresponding bicyclo[2.2.1]heptenes. The more flexible bicyclo[4.2.2]decene system already tends to undergo domino-Heck reactions, even under reductive conditions. When a tetracyclic cis-allylcyclopropane is carbopalladated in the presence of formates, the neighboring cyclopropane ring is attacked in the first reported example of a π,σ domino-Heck reaction. Full article
(This article belongs to the Special Issue Heck Coupling)
►▼ Show Figures

Figure 1

239 KiB  
Article
Relaxant Effect of the Ethanol Extract of Helichrysum plicatum (Asteraceae) on Isolated Rat Ileum Contractions
by Dubravka Bigovic, Suzana Brankovic, Dusanka Kitic, Mirjana Radenkovic, Teodora Jankovic, Katarina Savikin and Slavoljub Zivanovic
Molecules 2010, 15(5), 3391-3401; https://doi.org/10.3390/molecules15053391 - 10 May 2010
Cited by 29 | Viewed by 11575
Abstract
Helichrysum plicatum (Turkish Helichrysum) has been used in folk medicine for the treatment of gastric and hepatic disorders. The aim of the present study was to examine the relaxant activity of an extract of H. plicatum flowers on isolated rat ileum. Segments of [...] Read more.
Helichrysum plicatum (Turkish Helichrysum) has been used in folk medicine for the treatment of gastric and hepatic disorders. The aim of the present study was to examine the relaxant activity of an extract of H. plicatum flowers on isolated rat ileum. Segments of ileum of rats were suspended in an organ bath. Cumulative concentrations of H. plicatum ethanol extract induced a relaxant effect on spontaneous rat ileum contractions. H. plicatum extract caused a mean contractile response of 81.68 ± 6.17% (at a dose of 0.01 mg/mL) and 30.08 ± 9.07% (at a dose of 1 mg/mL). A similar effect was observed with papaverine (0.01–3 μg/mL). H. plicatum extract (0.01–1 mg/mL) relaxed high K+ (80 mM) precontractions, an effect similar to that caused by papaverine (0.01–3 μg/mL). The plant extract (0.03–0.3 mg/mL) also induced a significant depression of the cumulative concentration response curve for acetylcholine (5–1500 nM) (p < 0.01). Atropine (140 nM) abolished the acetylcholine effect. The extract (0.03–0.3 mg/mL) reduced the histamine (1–300 nM) and BaCl2 (3–900 μM) induced contractions (p < 0.01). Our results showed the relaxant effect of the ethanol extract of Helichrysum plicatum flowers on the isolated rat intestine Extract of H. plicatum can inhibit the spontaneous ileum contractions and contractions induced by acetylcholine, histamine, barium and potassium ions. Full article
►▼ Show Figures

Figure 1

378 KiB  
Article
In Vitro and in Vivo Effects of Laurus nobilis L. Leaf Extracts
by Biljana Kaurinovic, Mira Popovic and Sanja Vlaisavljevic
Molecules 2010, 15(5), 3378-3390; https://doi.org/10.3390/molecules15053378 - 7 May 2010
Cited by 46 | Viewed by 11253
Abstract
The in vitro and in vivo antioxidant activities of different extracts of laurel leaves were studied. Free radical scavenging capacity (RSC) was evaluated measuring the scavenging activity on the DPPH, NO, O2·- and OH radicals. The effects on lipid peroxidation (LP) [...] Read more.
The in vitro and in vivo antioxidant activities of different extracts of laurel leaves were studied. Free radical scavenging capacity (RSC) was evaluated measuring the scavenging activity on the DPPH, NO, O2·- and OH radicals. The effects on lipid peroxidation (LP) were also evaluated. Experimental results indicate that ethyl acetate extract of leaves has exhibited the largest RSC capacity in neutralization of DPPH, NO, O2·- and OH radicals. The same result was obtained in investigation of extracts impact on LP. The in vivo effects were evaluated on some antioxidant systems (activities of GSHPx, LPx, Px, CAT and XOD, and GSH content) in the mice liver and blood-hemolysate after treatment with the examined laurel extracts, or in combination with carbon tetrachloride (CCl4). On the basis of the results obtained it can be concluded that the examined extracts exhibited a certain protective effect, which is more pronounced on the liver than on blood-hemolysate parameters. The results obtained indicate toxicity of CCl4, probably due to the radicals involved in its metabolism. Combined treatments with CCl4 and the examined extracts showed both positive and negative synergism. Based on the experimental results, the strongest protective effect was shown by the EtOAc extract. Full article
413 KiB  
Article
Probing the Dynamics of Solvation and Structure of the OH- Ion in Aqueous Solution from Picosecond Transient Absorption Measurements
by Olivier Poizat and Guy Buntinx
Molecules 2010, 15(5), 3366-3377; https://doi.org/10.3390/molecules15053366 - 7 May 2010
Cited by 4 | Viewed by 8152
Abstract
The reaction of intracomplex proton transfer (44BPY-....HO-H) ® 44BPYH. + OH- that follows the photoreduction of 4,4’-bipyridine (44BPY) into its anion radical 44BPY- in the presence of 1,4-diazabicyclo[2.2.2]octane (DABCO) is investigated in acetonitrile-water mixtures by using picosecond transient [...] Read more.
The reaction of intracomplex proton transfer (44BPY-....HO-H) ® 44BPYH. + OH- that follows the photoreduction of 4,4’-bipyridine (44BPY) into its anion radical 44BPY- in the presence of 1,4-diazabicyclo[2.2.2]octane (DABCO) is investigated in acetonitrile-water mixtures by using picosecond transient absorption. The dependence of the appearance kinetics of the 44BPYH. radical on the water content reveals a highly diffusional proton transfer process that is controlled by the dynamics of solvation of the released hydroxide ion. The results are interpreted on the basis of a two-step mechanism where an intermediate solvation complex (44BPYH.)OH-(H2O)3 is formed first before evolving toward a final four-water hydration structure OH-(H2O)4. Full article
(This article belongs to the Special Issue Photochemistry in Organic Synthesis)
►▼ Show Figures

Graphical abstract

213 KiB  
Article
A LC-MS-Based Method for Quantification of Biomarkers from Serum of Allergic Rats
by Yu Jing Bai, Xiao Yan Gao, Jian Qiu Lu and Hong Gui Zhang
Molecules 2010, 15(5), 3356-3365; https://doi.org/10.3390/molecules15053356 - 7 May 2010
Cited by 6 | Viewed by 11375
Abstract
Allergies are highly complex disorders with clinical manifestations ranging from mild oral, gastrointestinal, recurrent wheezing, and cutaneous symptoms to life-threatening systemic conditions. The levels of arachidonic acid, eicosanoids, histamine, organic acids and valine are considered to have a variety of physiological functions in [...] Read more.
Allergies are highly complex disorders with clinical manifestations ranging from mild oral, gastrointestinal, recurrent wheezing, and cutaneous symptoms to life-threatening systemic conditions. The levels of arachidonic acid, eicosanoids, histamine, organic acids and valine are considered to have a variety of physiological functions in connection with allergies. In this research, we have developed a RP-LC/MS method to separate and quantitate six different potential endogenous biomarkers, including leukotrieneB4 (LTB4), prostaglandinD2 (PGD2), arachidonic acid (AA), histamine (HI), lactic acid (LA) and valine (VAL), from serum of rats with ovalbumin (OVA)-induced allergy and normal rats, and the discrepancies between the model group and the control group were compared. The separation was performed on a Prevail C18 column (250 mm × 4.6 mm, 5 μm) with a gradient elution of acetonitrile with 0.1% formic acid (v/v) and 10 mM ammonium formate (adjusted to pH 4.0 with formic acid) at a flow rate of 0.5 mL min−1 The method was validated and shown to be sensitive, accurate (recovery values 76.16–92.57%) and precise (RSD < 10% for all compounds) with a linear range over several orders of magnitude. The method was successfully applied to rat serum and shown to be indicative of the endogenous levels of biomarkers within the rat body. The analysis of the biomarkers can provide insight into the allergic mechanisms associated with related diseases. Full article
►▼ Show Figures

Graphical abstract

450 KiB  
Article
The Cinnamon-Derived Dietary Factor Cinnamic Aldehyde Activates the Nrf2-Dependent Antioxidant Response in Human Epithelial Colon Cells
by Georg Thomas Wondrak, Nicole F. Villeneuve, Sarah D. Lamore, Alexandra S. Bause, Tao Jiang and Donna D. Zhang
Molecules 2010, 15(5), 3338-3355; https://doi.org/10.3390/molecules15053338 - 7 May 2010
Cited by 134 | Viewed by 23603
Abstract
Colorectal cancer (CRC) is a major cause of tumor-related morbidity and mortality worldwide. Recent research suggests that pharmacological intervention using dietary factors that activate the redox sensitive Nrf2/Keap1-ARE signaling pathway may represent a promising strategy for chemoprevention of human cancer including CRC. In [...] Read more.
Colorectal cancer (CRC) is a major cause of tumor-related morbidity and mortality worldwide. Recent research suggests that pharmacological intervention using dietary factors that activate the redox sensitive Nrf2/Keap1-ARE signaling pathway may represent a promising strategy for chemoprevention of human cancer including CRC. In our search for dietary Nrf2 activators with potential chemopreventive activity targeting CRC, we have focused our studies on trans-cinnamic aldehyde (cinnamaldeyde, CA), the key flavor compound in cinnamon essential oil. Here we demonstrate that CA and an ethanolic extract (CE) prepared from Cinnamomum cassia bark, standardized for CA content by GC-MS analysis, display equipotent activity as inducers of Nrf2 transcriptional activity. In human colon cancer cells (HCT116, HT29) and non-immortalized primary fetal colon cells (FHC), CA- and CE-treatment upregulated cellular protein levels of Nrf2 and established Nrf2 targets involved in the antioxidant response including heme oxygenase 1 (HO-1) and γ-glutamyl-cysteine synthetase (γ-GCS, catalytic subunit). CA- and CE-pretreatment strongly upregulated cellular glutathione levels and protected HCT116 cells against hydrogen peroxide-induced genotoxicity and arsenic-induced oxidative insult. Taken together our data demonstrate that the cinnamon-derived food factor CA is a potent activator of the Nrf2-orchestrated antioxidant response in cultured human epithelial colon cells. CA may therefore represent an underappreciated chemopreventive dietary factor targeting colorectal carcinogenesis. Full article
(This article belongs to the Special Issue Antioxidants)
►▼ Show Figures

Graphical abstract

159 KiB  
Article
Synthesis and Chemical Characterisation of New Bis-Thieno [2,3-b]thiophene Derivatives
by Yahia Nasser Mabkhoot
Molecules 2010, 15(5), 3329-3337; https://doi.org/10.3390/molecules15053329 - 7 May 2010
Cited by 19 | Viewed by 7074
Abstract
Using 3-methyl-4-phenylthieno[2,3-b]thiophene-2,5-dicarbohydrazide as synthon a series of new bis-heterocycles incorporating the thieno[2,3-b]thiophene nucleus was prepared and characterized. Full article
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-57
Previous Issue
Next Issue
Back to TopTop