Molecules

273 KiB

Open AccessReview

Synthetic Approaches and Biological Activities of 4-Hydroxycoumarin Derivatives

by Jae-Chul Jung and Oee-Sook Park

Molecules 2009, 14(11), 4790-4803; https://doi.org/10.3390/molecules14114790 - 23 Nov 2009

Cited by 119 | Viewed by 14289

The main purpose of this review is to summarize recent chemical syntheses and structural modifications of 4-hydroxycoumarin and its derivatives, of interest due to their characteristic conjugated molecular architecture and biological activities. Full article

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185 KiB

Open AccessArticle

Silica Sulfuric Acid Promotes Aza-Michael Addition Reactions under Solvent-Free Condition as a Heterogeneous and Reusable Catalyst

by Yan Wang, Yan-Qin Yuan and Sheng-Rong Guo

Molecules 2009, 14(11), 4779-4789; https://doi.org/10.3390/molecules14114779 - 23 Nov 2009

Cited by 47 | Viewed by 10111

Abstract

A highly efficient, inexpensive, recyclable, convenient, and green protocol for chemoselective aza-Michael addition reactions of amines/thiols to α,β-unsaturated compounds using silica sulfuric acid (SSA or SiO₂-SO₃H) was developed. This method is simple, convenient and the title [...] Read more.

A highly efficient, inexpensive, recyclable, convenient, and green protocol for chemoselective aza-Michael addition reactions of amines/thiols to α,β-unsaturated compounds using silica sulfuric acid (SSA or SiO₂-SO₃H) was developed. This method is simple, convenient and the title compounds are produced in good to excellent yields. Full article

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564 KiB

Open AccessArticle

Spectroscopic Analyses of the Biofuels-Critical Phytochemical Coniferyl Alcohol and Its Enzyme-Catalyzed Oxidation Products

by Komandoor Elayavalli Achyuthan, Paul David Adams, Blake Alexander Simmons and Anup Kumar Singh

Molecules 2009, 14(11), 4758-4778; https://doi.org/10.3390/molecules14114758 - 23 Nov 2009

Cited by 3 | Viewed by 12051

Abstract

Lignin composition (monolignol types of coniferyl, sinapyl or p-coumaryl alcohol) is causally related to biomass recalcitrance. We describe multiwavelength (220, 228, 240, 250, 260, 290, 295, 300, 310 or 320 nm) absorption spectroscopy of coniferyl alcohol and its laccase- or peroxidase-catalyzed products [...] Read more.

Lignin composition (monolignol types of coniferyl, sinapyl or p-coumaryl alcohol) is causally related to biomass recalcitrance. We describe multiwavelength (220, 228, 240, 250, 260, 290, 295, 300, 310 or 320 nm) absorption spectroscopy of coniferyl alcohol and its laccase- or peroxidase-catalyzed products during real time kinetic, pseudokinetic and endpoint analyses, in optical turn on or turn off modes, under acidic or basic conditions. Reactions in microwell plates and 100 μL volumes demonstrated assay miniaturization and high throughput screening capabilities. Bathochromic and hypsochromic shifts along with hyperchromicity or hypochromicity accompanied enzymatic oxidations by laccase or peroxidase. The limits of detection and quantitation of coniferyl alcohol averaged 2.4 and 7.1 μM respectively, with linear trend lines over 3 to 4 orders of magnitude. Coniferyl alcohol oxidation was evident within 10 minutes or with 0.01 μg/mL laccase and 2 minutes or 0.001 μg/mL peroxidase. Detection limit improved to 1.0 μM coniferyl alcohol with Km of 978.7 ± 150.7 μM when examined at 260 nm following 30 minutes oxidation with 1.0 μg/mL laccase. Our assays utilized the intrinsic spectroscopic properties of coniferyl alcohol or its oxidation products for enabling detection, without requiring chemical synthesis or modification of the substrate or product(s). These studies facilitate lignin compositional analyses and augment pretreatment strategies for reducing biomass recalcitrance. Full article

(This article belongs to the Special Issue High-throughput Screening)

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403 KiB

Open AccessReview

Kinetic Resolution: A Powerful Tool for the Synthesis of Planar-Chiral Ferrocenes

by Andrea-Nekane R. Alba and Ramon Rios

Molecules 2009, 14(11), 4747-4757; https://doi.org/10.3390/molecules14114747 - 20 Nov 2009

Cited by 44 | Viewed by 10006

Abstract

Since the serendipitous discovery of ferrocene by Pauson and Kealy in 1951, it has become one of the most important structures in Organic Chemistry. Lately, kinetic resolution has emerged as a useful tool for the synthesis of planar chiral ferrocenes. This review aims [...] Read more.

Since the serendipitous discovery of ferrocene by Pauson and Kealy in 1951, it has become one of the most important structures in Organic Chemistry. Lately, kinetic resolution has emerged as a useful tool for the synthesis of planar chiral ferrocenes. This review aims to cover and discuss the development of this topic. Full article

(This article belongs to the Special Issue Ferrocenes)

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319 KiB

Open AccessArticle

Preparation of Superhydrophobic Polymeric Film on Aluminum Plates by Electrochemical Polymerization

by Fang Wang, Heyi Luo, Qian Wang, Jinggang Wang and Juan Xu

Molecules 2009, 14(11), 4737-4746; https://doi.org/10.3390/molecules14114737 - 19 Nov 2009

Cited by 29 | Viewed by 10518

Abstract

6-(N-Allyl-1,1,2,2-tetrahydroperfluorododecyl)amino-1,3,5-triazine-2,4-dithiol monosodium (ATP) was used to prepare polymeric thin films on pure aluminum plates to achieve a superhydrophobic surface. The electrochemical polymerization process of ATP on aluminum plates in NaNO₂ aqueous solution and the formation of poly(6-(N-allyl-1,1,2,2-tetrahydroperfluorododecyl)amino-1,3,5-triazine-2,4-dithiol) (PATP) [...] Read more.

6-(N-Allyl-1,1,2,2-tetrahydroperfluorododecyl)amino-1,3,5-triazine-2,4-dithiol monosodium (ATP) was used to prepare polymeric thin films on pure aluminum plates to achieve a superhydrophobic surface. The electrochemical polymerization process of ATP on aluminum plates in NaNO₂ aqueous solution and the formation of poly(6-(N-allyl-1,1,2,2-tetrahydroperfluorododecyl)amino-1,3,5-triazine-2,4-dithiol) (PATP) thin film were studied by means of optical ellipsometry and film weight. The chemical structure of the polymeric film is investigated using FT-IR spectra and X-ray photoelectron spectroscopy (XPS). Contact angle goniometry was applied to measure the contact angles with distilled water drops at ambient temperature. The experimental results indicate that the polymeric film formed on pure aluminum plates exhibits superhydrophobic properties with a distilled water contact angle of 153°. The electrochemical polymerization process is time-saving, inexpensive, environmentally friendly and fairly convenient to carry out. It is expected that this technique will advance the production of superhydrophobic materials with new applications on a large scale. Moreover, this kind of polymeric thin film can be used as a dielectric material due to its insulating features. Full article

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123 KiB

Open AccessArticle

Chemical Composition and Phytotoxic Effects of Essential Oils of Salvia hierosolymitana Boiss. and Salvia multicaulis Vahl. var. simplicifolia Boiss. Growing Wild in Lebanon

by Emilia Mancini, Nelly Apostolides Arnold, Laura De Martino, Vincenzo De Feo, Carmen Formisano, Daniela Rigano and Felice Senatore

Molecules 2009, 14(11), 4725-4736; https://doi.org/10.3390/molecules14114725 - 19 Nov 2009

Cited by 52 | Viewed by 11588

Abstract

The chemical composition of the essential oils of S. hierosolymitana Boiss. and S. multicaulis Vahl. var. simplicifolia Boiss. collected in Lebanon was studied by means of GC and GC-MS analysis. In all 115 compounds were identified: 82 for S hierosolymitana and 72 for [...] Read more.

The chemical composition of the essential oils of S. hierosolymitana Boiss. and S. multicaulis Vahl. var. simplicifolia Boiss. collected in Lebanon was studied by means of GC and GC-MS analysis. In all 115 compounds were identified: 82 for S hierosolymitana and 72 for S. multicaulis var. simplicifolia. The presence of carbonylic compounds (17%) characterizes the oil from S. hierosolymitana,while S. multicaulis var. simplicifolia oil is rich of monoterpenes (34.5%) and sesquiterpenes (46.9%). The effects of the essential oils on germination and initial radical elongation of Raphanus sativus L. (radish) and Lepidium sativum L. (garden cress) were studied, indicating in a different activity against radical elongation of the species tested. Full article

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Open AccessArticle

Njaoaminiums A, B, and C: Cyclic 3-Alkylpyridinium Salts from the Marine Sponge Reniera sp.

by Remi Laville, Grégory Genta-Jouve, Carlos Urda, Rogelio Fernández, Olivier P. Thomas, Fernando Reyes and Philippe Amade

Molecules 2009, 14(11), 4716-4724; https://doi.org/10.3390/molecules14114716 - 19 Nov 2009

Cited by 12 | Viewed by 10979

Abstract

Three novel cyclic 3-alkylpyridinium salts, named njaoaminiums A, B, and C (1-3), were isolated from the marine sponge Reniera sp., collected off the coasts of Pemba Island, Tanzania. The structural determination of the compounds was based on 1D and 2D NMR studies [...] Read more.

Three novel cyclic 3-alkylpyridinium salts, named njaoaminiums A, B, and C (1-3), were isolated from the marine sponge Reniera sp., collected off the coasts of Pemba Island, Tanzania. The structural determination of the compounds was based on 1D and 2D NMR studies and mass spectral determinations. Njaoaminiums B (2) and C (3) are the first examples of cyclic 3-alkylpyridinium salts bearing a methyl substituent on the alkyl chains. These compounds are assumed to be biosynthetic precursors of the njaoamines, previously isolated from the same sponge. The absolute configurations of the methyls of 2 and 3 were assigned by comparison between experimental and TDDFT calculated circular dichroism spectra on the most stable conformer. Compound 2 showed weak cytotoxicity against the three human tumor cell lines MDA-MB-231, A549, and HT29. Full article

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Open AccessArticle

Chemosystematic Value of the Essential Oil Composition of Thuja species Cultivated in Poland—Antimicrobial Activity

by Dimitroula Tsiri, Konstantia Graikou, Loretta Pobłocka-Olech, Miroslawa Krauze-Baranowska, Caroline Spyropoulos and Ioanna Chinou

Molecules 2009, 14(11), 4707-4715; https://doi.org/10.3390/molecules14114707 - 19 Nov 2009

Cited by 66 | Viewed by 11458

Abstract

In the framework of the correlation between chemotaxonomy and chemical analysis studies, the chemical composition of the essential oils of four varieties of Thuja species cultivated in Poland − T. occidentalis ‘globosa’, T. occidentalis ‘aurea’, T. plicata and T. plicata ‘gracialis’ [...] Read more.

In the framework of the correlation between chemotaxonomy and chemical analysis studies, the chemical composition of the essential oils of four varieties of Thuja species cultivated in Poland − T. occidentalis ‘globosa’, T. occidentalis ‘aurea’, T. plicata and T. plicata ‘gracialis’ − were investigated by GC and GC-MS. Thirty-one compounds were identified from T. occidentalis ‘globosa’, representing 96.92% of the total oil; twenty-seven from T. occidentalis ‘aurea’ (94.34%); thirty-one from T. plicata (94.75%); and thirty compounds from T. plicata ‘gracialis’ (96.36%). The main constituents in all samples were the monoterpene ketones α- and β-thujone, fenchone and sabinene, as well as the diterpenes beyerene and rimuene.The chemosystematic value of the total ketone content of all samples (which varied from 54.30–69.18%) has been discussed and investigated. The constituents, beyerene and the mixture of α- and β-thujone, were isolated from the oils and tested against six Gram-positive and -negative bacteria and three pathogenic fungi. The oils of the two T. plicata species exhibited significant antimicrobial activity, while the mixture of α- and β-thujone showed very strong activity as well. Full article

(This article belongs to the Special Issue Molecular Diversity Feature Papers)

58 KiB

Open AccessCorrection

Omran, O.-A. The Reaction of Diethyl Bromomalonate with p-tert-butylthiacalix[4]arene: An Approach to Asymmetrical Derivatives Molecules 2009, 14, 1755-1761

by Omran Abdellah Omran

Molecules 2009, 14(11), 4689; https://doi.org/10.3390/molecules14114689 - 19 Nov 2009

Viewed by 6309

Abstract

We found following errors in our paper published in Molecules recently [1]. [...] Full article

1064 KiB

Open AccessReview

Steroidal Triterpenes: Design of Substrate-Based Inhibitors of Ergosterol and Sitosterol Synthesis

by Jialin Liu and William David Nes

Molecules 2009, 14(11), 4690-4706; https://doi.org/10.3390/molecules14114690 - 18 Nov 2009

Cited by 24 | Viewed by 19538

Abstract

This article reviews the design and study, in our own laboratory and others, of new steroidal triterpenes with a modified lanosterol or cycloartenol frame. These compounds, along with a number of known analogs with the cholestane skeleton, have been evaluated as reversible or [...] Read more.

This article reviews the design and study, in our own laboratory and others, of new steroidal triterpenes with a modified lanosterol or cycloartenol frame. These compounds, along with a number of known analogs with the cholestane skeleton, have been evaluated as reversible or irreversible inhibitors of sterol C24-methyltransferase (SMT) from plants, fungi and protozoa. The SMT catalyzes the C24-methylation reaction involved with the introduction of the C24-methyl group of ergosterol and the C24-ethyl group of sitosterol, cholesterol surrogates that function as essential membrane inserts in many photosynthetic and non-photosynthetic eukaryotic organisms. Sterol side chains constructed with a nitrogen, sulfur, bromine or fluorine atom, altered to possess a methylene cyclopropane group, or elongated to include terminal double or triple bonds are shown to exhibit different in vitro activities toward the SMT which are mirrored in the inhibition potencies detected in the growth response of treated cultured human and plant cells or microbes. Several of the substrate-based analogs surveyed here appear to be taxaspecific compounds acting as mechanism-based inactivators of the SMT, a crucial enzyme not synthesized by animals. Possible mechanisms for the inactivation process and generation of novel products catalyzed by the variant SMTs are discussed. Full article

(This article belongs to the Special Issue Triterpenes and Triterpenoids 2013)

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Graphical abstract

764 KiB

Open AccessArticle

Cellulose/Gold Nanocrystal Hybrids via an Ionic Liquid/Aqueous Precipitation Route

by Zhonghao Li and Andreas Taubert

Molecules 2009, 14(11), 4682-4688; https://doi.org/10.3390/molecules14114682 - 18 Nov 2009

Cited by 20 | Viewed by 9562

Abstract

Injection of a mixture of HAuCl₄ and cellulose dissolved in the ionic liquid (IL) 1-butyl-3-methylimidazolium chloride [Bmim]Cl into aqueous NaBH4 leads to colloidal gold nanoparticle/cellulose hybrid precipitates. This process is a model example for a very simple and generic approach towards (noble) [...] Read more.

Injection of a mixture of HAuCl₄ and cellulose dissolved in the ionic liquid (IL) 1-butyl-3-methylimidazolium chloride [Bmim]Cl into aqueous NaBH4 leads to colloidal gold nanoparticle/cellulose hybrid precipitates. This process is a model example for a very simple and generic approach towards (noble) metal/cellulose hybrids, which could find applications in sensing, sterile filtration, or as biomaterials. Full article

(This article belongs to the Collection Ionic Liquids)

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384 KiB

Open AccessArticle

New Lipophilic Piceatannol Derivatives Exhibiting Antioxidant Activity Prepared by Aromatic Hydroxylation with 2-Iodoxybenzoic Acid (IBX)

by Roberta Bernini, Maurizio Barontini and Carmela Spatafora

Molecules 2009, 14(11), 4669-4681; https://doi.org/10.3390/molecules14114669 - 17 Nov 2009

Cited by 22 | Viewed by 10771

Abstract

Piceatannol (E-3,5,3’,4’-tetrahydroxystilbene) is a phytoalexin synthesized in grapes in response to stress conditions. It exhibits strong antioxidant and antileukaemic activities due to the presence of the catechol moiety. To modify some physical properties like solubility, and miscibility in non-aqueous media some [...] Read more.

Piceatannol (E-3,5,3’,4’-tetrahydroxystilbene) is a phytoalexin synthesized in grapes in response to stress conditions. It exhibits strong antioxidant and antileukaemic activities due to the presence of the catechol moiety. To modify some physical properties like solubility, and miscibility in non-aqueous media some new previously unreported piceatannol derivatives having lipophilic chains on the A-ring were prepared in good yields by a simple and efficient procedure. The key step was a chemo- and regioselective aromatic hydroxylation with 2-iodoxybenzoic acid (IBX). The new compounds showed antioxidant activity and seemed promising for possible applications as multifunctional emulsifiers in food, cosmetic and pharmaceutical fields. Full article

(This article belongs to the Special Issue Organic Iodine Chemistry)

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572 KiB

Open AccessArticle

Synthesis of Pregnane Derivatives, Their Cytotoxicity on LNCap and PC-3 Cells, and Screening on 5α-Reductase Inhibitory Activity

by Sujeong Kim and Eunsook Ma

Molecules 2009, 14(11), 4655-4668; https://doi.org/10.3390/molecules14114655 - 17 Nov 2009

Cited by 21 | Viewed by 8739

Abstract

A series of epoxy- and/or 20-oxime pregnanes were synthesized from commercially available pregnenolone. Compounds 1, 3, 7, 8 and 11-13 were evaluated for cytotoxicity activity towards LNCaP (androgen-dependent) and PC-3 (androgenindependent) prostate cancer cells. Compound 13 showed the highest activity on both LNCaP [...] Read more.

A series of epoxy- and/or 20-oxime pregnanes were synthesized from commercially available pregnenolone. Compounds 1, 3, 7, 8 and 11-13 were evaluated for cytotoxicity activity towards LNCaP (androgen-dependent) and PC-3 (androgenindependent) prostate cancer cells. Compound 13 showed the highest activity on both LNCaP (IC₅₀ 15.17 μM) and PC-3 (IC₅₀11.83 μM) cell lines. Compound 11 showed weak activity on LNCaP cells (IC₅₀ 71.85 μM) and 8 showed the weak activity on PC-3 cells (IC₅₀ 68.95 μM), respectively. The 5α-reductase II (5AR2) inhibitory effects of compounds 1-3, 5 and 7-13 were investigated in a convenient screening model, in which compounds 5, 8, 11 and 12 were observed to be potential inhibitors of 5α-reductase, in particular, the 4-azasteroid 11, that also inhibited cell proliferation of androgen-dependent cells and 8, that in addition inhibited PC-3 cells more potently than LNCaP cells. Full article

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Open AccessArticle

High-Performance Liquid Chromatographic Quantification of Flavonoids in Eriocaulaceae Species and Their Antimicrobial Activity

by Marcelo Aparecido Da Silva, Claudia Andréa Lima Cardoso, Wagner Vilegas and Lourdes Campaner Dos Santos

Molecules 2009, 14(11), 4644-4654; https://doi.org/10.3390/molecules14114644 - 16 Nov 2009

Cited by 11 | Viewed by 11280

Abstract

Quantification of prepared samples by analysis using high performance liquid chromatography with DAD detection was developed to analyze rutin, 6-methoxyapigenin, and 6-methoxyapigenin-7-O-β-D-glucopyranoside isolated from methanolic extracts of different genus: Syngonanthus, Leiothix and Eriocaulon (Eriocaulaceae). The linearity, accuracy, and the inter-day [...] Read more.

Quantification of prepared samples by analysis using high performance liquid chromatography with DAD detection was developed to analyze rutin, 6-methoxyapigenin, and 6-methoxyapigenin-7-O-β-D-glucopyranoside isolated from methanolic extracts of different genus: Syngonanthus, Leiothix and Eriocaulon (Eriocaulaceae). The linearity, accuracy, and the inter-day precision of the procedure were evaluated. The calibration curves were linear. The recoveries of the flavonoids in the samples analyzed were 96.3% to 98.5%. The percentage coefficient of variation for the quantitative analysis of the flavonoids in the analyses of the samples was under 5%. The antimicrobial activity of the five methanol extracts of these Eriocaulaceae species was assayed against the microorganisms Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Salmonella setubal, Saccharomyces cerevisiae and Candida albicans. Measured MIC values ranged from 1.25 to 10.00 mg/mL. The flavonoid contents suggest that Eriocaulaceae species may be a promising source of compounds to produce natural phytomedicines. Full article

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239 KiB

Open AccessArticle

3-(2-Aminophenyl)-4-methyl-1,3-thiazole-2(3H)-thione as an Ecofriendly Sulphur Transfer Agent to Prepare Alkanethiols in High Yield and High Purity

by Mohammed Amine Mehdid, Ayada Djafri, Christian Roussel and Federico Andreoli

Molecules 2009, 14(11), 4634-4643; https://doi.org/10.3390/molecules14114634 - 12 Nov 2009

Cited by 5 | Viewed by 11771

Abstract

A new process is described for preparing very pure linear alkanethiols and linear α,ω-alkanedithiols using a sequential alkylation of the title compound, followed by a ring closure to quantitatively give the corresponding 3-methyl[1,3]thiazolo[3,2-a]-[3,1]benzimidazol-9-ium salt and the alkanethiol derivative under mild conditions. The alkanethiol [...] Read more.

A new process is described for preparing very pure linear alkanethiols and linear α,ω-alkanedithiols using a sequential alkylation of the title compound, followed by a ring closure to quantitatively give the corresponding 3-methyl[1,3]thiazolo[3,2-a]-[3,1]benzimidazol-9-ium salt and the alkanethiol derivative under mild conditions. The alkanethiol and the heteroaromatic salt are easily separated by a simple extraction process. The intermediate thiazolium quaternary salts resulting from the first reaction step can be isolated in quantitative yields, affording an odourless protected form of the thiols. Full article

(This article belongs to the Special Issue Advances in Heteroaromatic Chemistry)

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278 KiB

Open AccessCommunication

Study of the Chemical Composition of the Resinous Exudate Isolated from Heliotropium Sclerocarpum and Evaluation of the Antioxidant Properties of the Phenolic Compounds and the Resin

by Brenda Modak, Melissa Salina, Jesús Rodilla and René Torres

Molecules 2009, 14(11), 4625-4633; https://doi.org/10.3390/molecules14114625 - 12 Nov 2009

Cited by 23 | Viewed by 11229

Abstract

Heliotropium sclerocarpum Phil. (Heliotropiaceae) is a resinous bush that grows in the Atacama of northern Chile. The chemical composition of its resinous exudate was analyzed for the first time. One aromatic geranyl derivative: filifolinol (1), one flavanone: naringenin (2) and a [...] Read more.

Heliotropium sclerocarpum Phil. (Heliotropiaceae) is a resinous bush that grows in the Atacama of northern Chile. The chemical composition of its resinous exudate was analyzed for the first time. One aromatic geranyl derivative: filifolinol (1), one flavanone: naringenin (2) and a new type of 3-oxo-2-arylbenzofuran derivative 3 were isolated and their structures were determined. The antioxidant activity of the phenolic compounds and resin was evaluated using the bleaching of DPPH radical method and expressed as fast reacting equivalents (FRE) and total reacting equivalents (TRE). Full article

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145 KiB

Open AccessArticle

Chemical Composition and Antimicrobial Activity of the Essential Oils from Two Species of Thymus Growing Wild in Southern Italy

by Laura De Martino, Maurizio Bruno, Carmen Formisano, Vincenzo De Feo, Francesco Napolitano, Sergio Rosselli and Felice Senatore

Molecules 2009, 14(11), 4614-4624; https://doi.org/10.3390/molecules14114614 - 12 Nov 2009

Cited by 60 | Viewed by 11351

Abstract

The volatile constituents of the aerial parts of two samples of Thymus longicaulis C. Presl, collected in Campania and in Sicily, and two samples of Thymus pulegioides L. from the same regions, were extracted by hydrodistillation and analyzed. Considering the four oils together, [...] Read more.

The volatile constituents of the aerial parts of two samples of Thymus longicaulis C. Presl, collected in Campania and in Sicily, and two samples of Thymus pulegioides L. from the same regions, were extracted by hydrodistillation and analyzed. Considering the four oils together, seventy-eight different compounds were identified: 57 for Thymus longicaulis from Sicily (91.1% of the total oil), 40 for Thymus longicaulis from Campania (91.5% of the oil), 39 for Thymus pulegioides from Sicily (92.5% of the oil) and 29 for Thymus pulegioides from Campania (90.1% of the oil). The composition of the oils is different, although the most abundant components are identical in T. pulegioides. The essential oils showed antibacterial activity against eight selected microorganisms. Full article

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Open AccessArticle

Headspace Volatile Composition of the Flowers of Caralluma europaea N.E.Br. (Apocynaceae)

by Carmen Formisano, Felice Senatore, Giovanna Della Porta, Mariarosa Scognamiglio, Maurizio Bruno, Antonella Maggio, Sergio Rosselli, Pietro Zito and Maurizio Sajeva

Molecules 2009, 14(11), 4597-4613; https://doi.org/10.3390/molecules14114597 - 11 Nov 2009

Cited by 31 | Viewed by 11434

Abstract

The volatile constituents of the flowers of Caralluma europaea (Guss.) N.E.Br (Apocynaceae) from Lampedusa Island were analyzed by a headspace GC method. The analyses allowed the identification and quantification of 41 compounds. The main components were, among the monoterpenoids, terpinolene (23.3%), α-terpinene (19.1%) [...] Read more.

The volatile constituents of the flowers of Caralluma europaea (Guss.) N.E.Br (Apocynaceae) from Lampedusa Island were analyzed by a headspace GC method. The analyses allowed the identification and quantification of 41 compounds. The main components were, among the monoterpenoids, terpinolene (23.3%), α-terpinene (19.1%) and linalool (18.4%), whereas, among the carbonylic compounds the major constituents were heptanal (2.0%), octanoic acid (2.4%) and hexanoic acid (1.7%). The presence of a nitrogen containing compound, indole (0.8%) and of a sulphur containing compound, dimethylsulphide (t), noteworthy. The compounds found in the flowers of C. europaea have been compared with data available in the literature as regard to their odor, presence in other sapromyiophilous taxa, possible role as semiochemicals, and presence in decaying organic matter. 89.3% of total constituents have been described in other sapromyiophilous taxa. Some of the compounds are present in several types of decaying organic matter (excrements, decomposing bodies, and spoiled fish, etc). Several volatiles found in C. europaea flowers are used as semiochemicals by Hymenoptera, Coleoptera, Diptera, Lepidoptera and other insects. Sixteen volatiles, accounting for 32.4% of the total constituents, are described as attractants of some Diptera families, with a biology linked to decaying organic matter. Our data thus confirm that C. europaea floral bouquet falls within the sapromyiophilous pollination syndrome. Full article

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Open AccessArticle

A New Norsesquiterpenoid from a Bornean Soft Coral Genus Nephthea

by Takahiro Ishii, Hiroshi Matsuura, Zhan Zhaoqi and Charles Santhanaraju Vairappan

Molecules 2009, 14(11), 4591-4596; https://doi.org/10.3390/molecules14114591 - 10 Nov 2009

Cited by 14 | Viewed by 7710

Abstract

A new germacrane-type norsesquiterpenoid, 1-acetoxy-germacra-5E,10(14)-diene-4-one (1), as well as three known compounds, were isolated from the organic extracts of a Bornean soft coral Nephthea sp. Their structures were elucidated on the basis of spectroscopic data analysis. Full article

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Open AccessReview

The Trypanocidal Activity of Naphthoquinones: A Review

by Antônio Ventura Pinto and Solange Lisboa de Castro

Molecules 2009, 14(11), 4570-4590; https://doi.org/10.3390/molecules14114570 - 10 Nov 2009

Cited by 191 | Viewed by 17303

Abstract

Naphthoquinones are compounds present in several families of higher plants. Their molecular structures confer redox properties, and they are involved in multiple biological oxidative processes. In folk medicine, especially among Indian populations, plants containing naphthoquinones have been employed for the treatment of various [...] Read more.

Naphthoquinones are compounds present in several families of higher plants. Their molecular structures confer redox properties, and they are involved in multiple biological oxidative processes. In folk medicine, especially among Indian populations, plants containing naphthoquinones have been employed for the treatment of various diseases. The biological redox cycle of quinones can be initiated by one electron reduction leading to the formation of semiquinones, unstable intermediates that react rapidly with molecular oxygen, generating free radicals. Alternatively, the reduction by two electrons, mediated by DT-diphorase, leads to the formation of hydroquinone. Lapachol, α-lapachone and β-lapachone, which are isolated from the heartwood of trees of the Bignoniaceae family, are examples of bioactive naphthoquinones. In this review, we will discuss studies investigating the activity of these natural products and their derivatives in the context of the search for alternative drugs for Chagas disease, caused by Trypanosoma cruzi, a neglected illness that is endemic in Latin America. Full article

(This article belongs to the Special Issue Neglected Diseases: Medicinal Chemistry and Natural Product Chemistry)

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406 KiB

Open AccessReview

Simple Sequence Repeat Polymorphisms (SSRPs) for Evaluation of Molecular Diversity and Germplasm Classification of Minor Crops

by Yong-Jin Park, Ju Kyong Lee and Nam-Soo Kim

Molecules 2009, 14(11), 4546-4569; https://doi.org/10.3390/molecules14114546 - 10 Nov 2009

Cited by 124 | Viewed by 15396

Abstract

Evaluation of the genetic diversity among populations is an essential prerequisite for the preservation of endangered species. Thousands of new accessions are introduced into germplasm institutes each year, thereby necessitating assessment of their molecular diversity before elimination of the redundant genotypes. Of the [...] Read more.

Evaluation of the genetic diversity among populations is an essential prerequisite for the preservation of endangered species. Thousands of new accessions are introduced into germplasm institutes each year, thereby necessitating assessment of their molecular diversity before elimination of the redundant genotypes. Of the protocols that facilitate the assessment of molecular diversity, SSRPs (simple sequence repeat polymorphisms) or microsatellite variation is the preferred system since it detects a large number of DNA polymorphisms with relatively simple technical complexity. The paucity of information on DNA sequences has limited their widespread utilization in the assessment of genetic diversity of minor or neglected crop species. However, recent advancements in DNA sequencing and PCR technologies in conjunction with sophisticated computer software have facilitated the development of SSRP markers in minor crops. This review examines the development and molecular nature of SSR markers, and their utilization in many aspects of plant genetics and ecology. Full article

(This article belongs to the Special Issue Molecular Diversity Feature Papers)

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390 KiB

Open AccessReview

Bystander or No Bystander for Gene Directed Enzyme Prodrug Therapy

by Gabi U. Dachs, Michelle A. Hunt, Sophie Syddall, Dean C. Singleton and Adam V. Patterson

Molecules 2009, 14(11), 4517-4545; https://doi.org/10.3390/molecules14114517 - 10 Nov 2009

Cited by 96 | Viewed by 16032

Abstract

Gene directed enzyme prodrug therapy (GDEPT) of cancer aims to improve the selectivity of chemotherapy by gene transfer, thus enabling target cells to convert nontoxic prodrugs to cytotoxic drugs. A zone of cell kill around gene-modified cells due to transfer of toxic metabolites, [...] Read more.

Gene directed enzyme prodrug therapy (GDEPT) of cancer aims to improve the selectivity of chemotherapy by gene transfer, thus enabling target cells to convert nontoxic prodrugs to cytotoxic drugs. A zone of cell kill around gene-modified cells due to transfer of toxic metabolites, known as the bystander effect, leads to tumour regression. Here we discuss the implications of either striving for a strong bystander effect to overcome poor gene transfer, or avoiding the bystander effect to reduce potential systemic effects, with the aid of three successful GDEPT systems. This review concentrates on bystander effects and drug development with regard to these enzyme prodrug combinations, namely herpes simplex virus thymidine kinase (HSV-TK) with ganciclovir (GCV), cytosine deaminase (CD) from bacteria or yeast with 5-fluorocytodine (5-FC), and bacterial nitroreductase (NfsB) with 5-(azaridin-1-yl)-2,4-dinitrobenzamide (CB1954), and their respective derivatives. Full article

(This article belongs to the Special Issue Prodrugs)

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354 KiB

Open AccessArticle

Antioxidant Effects of Some Drugs on Immobilization Stress Combined with Cold Restraint Stress

by Mira Popovic, Snezana Janicijevic-Hudomal, Biljana Kaurinovic, Julijana Rasic, Svetlana Trivic and Matilda Vojnović

Molecules 2009, 14(11), 4505-4516; https://doi.org/10.3390/molecules14114505 - 10 Nov 2009

Cited by 22 | Viewed by 9762

Abstract

The aim of this work was to investigate the effect on antioxidant potential of some commonly used drugs (morphine, tramadol, bromocriptine, haloperidol and azithromycin) on immobilization stress (IS) combined with cold restraint stress (CRS) in the rat. After the drug treatment the animals [...] Read more.

The aim of this work was to investigate the effect on antioxidant potential of some commonly used drugs (morphine, tramadol, bromocriptine, haloperidol and azithromycin) on immobilization stress (IS) combined with cold restraint stress (CRS) in the rat. After the drug treatment the animals were kept immobilized in the cold chamber at 4±0.3ºC for 3 hours and then decapitaed and the livers were extracted. The following parameters were determined in the liver homogenate: content of reduced glutathione, activities of catalase, xanthine oxidase, glutathione reductase, glutathione peroxidase, peroxidase, and lipid peroxidation intensity. A battery of biochemical assays was used and the resulting data were statistically analyzed. Combined stress exhibited a prooxidative action (increased catalase activity, lowered content of reduced glutathione). Significantly enhanced catalase activity that was observed in all groups compared to the control indicates that the primary reactive oxygen species (ROS) metabolite is hydrogen peroxide, which decomposes very rapidly (very high catalase activity), thus hindering formation of OH radicals as the most toxic ROS. None of the tested drugs showed a protective effect on combined IS and CRS. The intensity of lipid peroxidation did not change either in the combined stress or under additional influence of the drugs. Probably, under our experimental conditions, the time was not sufficiently long to observe damage of lipid membrane by ROS. Full article

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Open AccessCommunication

A New Triterpene Hexaglycoside from the Bark of Kalopanax septemlobus (Thunb.) Koidz.

by Li-Shu Wang, Da-Qing Zhao, Tun-Hai Xu, Xue-Feng Zhou, Xian-Wen Yang and Yong-Hong Liu

Molecules 2009, 14(11), 4497-4504; https://doi.org/10.3390/molecules14114497 - 09 Nov 2009

Cited by 6 | Viewed by 11287

Abstract

The new triterpene glycoside 3-O-β-D-xylopyranosyl-(1→4)-β-D-xylopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosylhederagenin 28-O-β-D-gluco-pyranosyl-(1→6)-β-D-glucopyranoside, named septemoside A (1), and the known 3-O-α-L-rhamnopyranosyl-(1→2)-O-α-L-arabinopyranoside-28-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl ester of hederagenin (2), were isolated from the bark of Kalopanax septemlobus. The structure elucidation of [...] Read more.

The new triterpene glycoside 3-O-β-D-xylopyranosyl-(1→4)-β-D-xylopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosylhederagenin 28-O-β-D-gluco-pyranosyl-(1→6)-β-D-glucopyranoside, named septemoside A (1), and the known 3-O-α-L-rhamnopyranosyl-(1→2)-O-α-L-arabinopyranoside-28-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl ester of hederagenin (2), were isolated from the bark of Kalopanax septemlobus. The structure elucidation of the compounds was based on spectroscopic evidence, including HRESIMS, 1D and 2D-NMR analysis. Full article

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338 KiB

Open AccessArticle

A Selective Pharmacophore Model for β₂-Adrenoceptor Agonists

by Rui-Juan Xing, Jian Wang, Li Pan and Mao-Sheng Cheng

Molecules 2009, 14(11), 4486-4496; https://doi.org/10.3390/molecules14114486 - 06 Nov 2009

Cited by 5 | Viewed by 9421

Abstract

β₂-Adrenoceptor selectivity is an important consideration in drug design in order to minimize the possibility of side effects. A selective pharmacophore model was developed based on a series of selective β₂-adrenoceptor agonists. The best pharmacophore hypothesis consisted of five [...] Read more.

β₂-Adrenoceptor selectivity is an important consideration in drug design in order to minimize the possibility of side effects. A selective pharmacophore model was developed based on a series of selective β₂-adrenoceptor agonists. The best pharmacophore hypothesis consisted of five chemical features (one hydrogen-bond acceptor, one hydrogen-bond donor, two ring aromatic and one positive ionizable feature). The result was nearly in accordance with the reported interactions between the β₂-adrenoceptor and agonists, and it shared enough similar features with the result of field point patterns by FieldTemplater, which mainly validated the pharmacophore model. Moreover, the pharmacophore could predict the selectivity over the β₁-adrenoceptor. These results might provide guidance for the rational design of novel potent and selective β₂-adrenoceptor agonists. Full article

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272 KiB

Open AccessArticle

In Vitro Antioxidant and Xanthine Oxidase Inhibitory Activities of Methanolic Swietenia mahagoni Seed Extracts

by Geethaa Sahgal, Surash Ramanathan, Sreenivasan Sasidharan, Mohd Nizam Mordi, Sabariah Ismail and Sharif Mahsufi Mansor

Molecules 2009, 14(11), 4476-4485; https://doi.org/10.3390/molecules14114476 - 06 Nov 2009

Cited by 71 | Viewed by 13066

Abstract

This study examines the in vitro antioxidant activities of the methanol extract of Swietenia mahagoni seeds (SMCM seed extract). The extract was screened for possible antioxidant activities by free radical scavenging activity (DPPH), xanthine oxidase inhibition (XOI), hydrogen peroxide scavenging activity (HPSA) and [...] Read more.

This study examines the in vitro antioxidant activities of the methanol extract of Swietenia mahagoni seeds (SMCM seed extract). The extract was screened for possible antioxidant activities by free radical scavenging activity (DPPH), xanthine oxidase inhibition (XOI), hydrogen peroxide scavenging activity (HPSA) and ferric-reducing antioxidant power (FRAP) assays. The total phenolic and flavonoid contents were also determined. The extract exhibits antioxidant activity of 23.29% with an IC₅₀value of 2.3 mg/mL in the DPPH radical scavenging method, 47.2% in the XOI assay, 49.5% by the HPSA method, and 0.728 mmol/Fe(II)g in the FRAP method at the concentration tested. The amount of total phenolics and flavonoid contents was 70.83 mg gallic acid equivalent (GAE) and 2.5 ± 0.15 mg of catechin equivalent per gram of dry extract, respectively. High Performance Thin Layer Chromatography (HPTLC) screening indicates the presence of phenolic compounds in the SMCM seed extract. The results indicate that the extract has both high free radical scavenging and xanthine oxidase inhibition activity. The antioxidant activity of SMCM seed extract is comparable with that of other Malaysian tropical fruits and herbal plants. Full article

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381 KiB

Open AccessReview

¹³C-NMR Data of Three Important Diterpenes Isolated from Euphorbia Species

by Qi-Cheng Wu, Yu-Ping Tang, An-Wei Ding, Fen-Qiang You, Li Zhang and Jin-Ao Duan

Molecules 2009, 14(11), 4454-4475; https://doi.org/10.3390/molecules14114454 - 06 Nov 2009

Cited by 46 | Viewed by 12519

Abstract

Euphorbia species are widely distributed plants, many of which are used in folk medicine. Over the past twenty years, they have received considerable phytochemical and biological attention. Their diterpenoid constituents, especially those with abietane, tigliane, ingenane skeletons, are thought to be the main [...] Read more.

Euphorbia species are widely distributed plants, many of which are used in folk medicine. Over the past twenty years, they have received considerable phytochemical and biological attention. Their diterpenoid constituents, especially those with abietane, tigliane, ingenane skeletons, are thought to be the main toxicant and bioactive factors. In this work, the utility of ¹³C-NMR spectroscopy for the structural elucidation of these compounds is briefly discussed. Full article

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275 KiB

Open AccessArticle

The Effect of Long-Running Severe Selenium-Deficiency on the Amount of Iron and Zinc in the Organs of Rats

by Ken-ichiro Matsumoto, Sachiyo Terada, Marie Ariyoshi, Aya Okajo, Atsushi Hisamatsu, Iori Ui and Kazutoyo Endo

Molecules 2009, 14(11), 4440-4453; https://doi.org/10.3390/molecules14114440 - 05 Nov 2009

Cited by 7 | Viewed by 8375

Abstract

The amounts of selenium (Se), iron (Fe), and zinc (Zn) in the liver, kidney, and spleen as a function of age of rats measured using instrumental neutron activation analysis were compared between Se-deficient (SeD) rats and normal rats. The SeD model rats can [...] Read more.

The amounts of selenium (Se), iron (Fe), and zinc (Zn) in the liver, kidney, and spleen as a function of age of rats measured using instrumental neutron activation analysis were compared between Se-deficient (SeD) rats and normal rats. The SeD model rats can live for more than 50 weeks. The effect of Se-deficinecy in rats might be weak, compared to the marked malfunction of GSH-Px. The SeD rats can be considered as a model of nonlethal chronic oxidative stress. Fluctuations of Fe and Zn in the liver of Se-deficient rats were observed. The amount of redox-relating minerals, such as Fe and Zn, in SeD rat organs is changeable depending on the age. Full article

(This article belongs to the Special Issue Selenium and Tellurium Chemistry)

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196 KiB

Open AccessCommunication

Chemical Constituents from Clematis delavayi var. spinescens

by Yang Li, Si-Feng Wang, Yan-Li Zhao, Ke-Chun Liu, Xi-Min Wang, Yong-Ping Yang and Xiao-Li Li

Molecules 2009, 14(11), 4433-4439; https://doi.org/10.3390/molecules14114433 - 05 Nov 2009

Cited by 16 | Viewed by 10188

Abstract

A new coumarin, 7-hydroxy-4,6-dimethoxy-5-methylcoumarin (1), was isolated from the aerial parts of Clematis delavayi var. spinescens together with 17 known compounds. Their structures were identified by extensive spectral analysis, especially 2D NMR techniques. Antiangiogenic effects of all compounds were evaluated using a zebrafish [...] Read more.

A new coumarin, 7-hydroxy-4,6-dimethoxy-5-methylcoumarin (1), was isolated from the aerial parts of Clematis delavayi var. spinescens together with 17 known compounds. Their structures were identified by extensive spectral analysis, especially 2D NMR techniques. Antiangiogenic effects of all compounds were evaluated using a zebrafish model. Full article

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737 KiB

Open AccessCommunication

Depigmenting Effect of Catechins

by Kazuomi Sato and Masaru Toriyama

Molecules 2009, 14(11), 4425-4432; https://doi.org/10.3390/molecules14114425 - 04 Nov 2009

Cited by 57 | Viewed by 8984

Abstract

The aim of the present work was to clarify the anti-melanogenic mechanism of the catechin group. In this study, we used (-)-epigallocatechin-3-gallate (EGCG), (-)-epigallocatechin (EGC), (-)-catechin (C), and gallic acid (GA). The catechin group inhibited melanin synthesis in B16 melanoma cells. To elucidate [...] Read more.

The aim of the present work was to clarify the anti-melanogenic mechanism of the catechin group. In this study, we used (-)-epigallocatechin-3-gallate (EGCG), (-)-epigallocatechin (EGC), (-)-catechin (C), and gallic acid (GA). The catechin group inhibited melanin synthesis in B16 melanoma cells. To elucidate the anti-melanogenic mechanism of the catechin group, we performed Western blotting analysis for crucial melanogenic protein, namely tyrosinase. The catechin group inhibited tyrosinase expression. These results indicate that the catechin group is a candidate anti-melanogenic agent and that it might be effective in hyperpigmentation disorders. Full article

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Molecules, Volume 14, Issue 11 (November 2009) – 41 articles , Pages 4300-4803

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