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Molecules, Volume 18, Issue 2 (February 2013), Pages 1337-2457

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Open AccessCommunication Brazilin Inhibits Growth and Induces Apoptosis in Human Glioblastoma Cells
Molecules 2013, 18(2), 2449-2457; https://doi.org/10.3390/molecules18022449
Received: 26 November 2012 / Revised: 31 January 2013 / Accepted: 6 February 2013 / Published: 21 February 2013
Cited by 20 | PDF Full-text (276 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Brazilin, isolated from the methanol extract of the heart wood of Caesalpinia sappan, sensitizes cancer cells to apoptosis. Glioblastoma multiforme (GBM), which accounts for most cases of central nervous system malignancy, has a very poor prognosis and lacks effective therapeutic interventions. We,
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Brazilin, isolated from the methanol extract of the heart wood of Caesalpinia sappan, sensitizes cancer cells to apoptosis. Glioblastoma multiforme (GBM), which accounts for most cases of central nervous system malignancy, has a very poor prognosis and lacks effective therapeutic interventions. We, therefore, investigated the effects of different concentrations of and different periods of exposure to brazilin on cell proliferation and apoptosis in the glioma U87 cell line. Cell proliferation was investigated by MTT assays and growth curve analysis, apoptosis was assessed by FACS analysis and western blot studies. Brazilin showed dose-dependent inhibition of cell proliferation and induction of apoptosis in glioma cells. It also increased the ratio of cleaved poly-(ADP)-ribose polymerase and decreased the expression of caspase-3 and caspase-7. Full article
(This article belongs to the Section Medicinal Chemistry)
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Open AccessArticle The Tandem Ring Opening/Ring Closing Metathesis Route to Oxaspirocycles: An Approach to Phelligridin G
Molecules 2013, 18(2), 2438-2448; https://doi.org/10.3390/molecules18022438
Received: 4 December 2012 / Revised: 31 January 2013 / Accepted: 7 February 2013 / Published: 21 February 2013
Cited by 10 | PDF Full-text (310 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Phelligridin G is an unusual natural product that contains an embedded spiro-fused furanone core. We have investigated two furan-based synthetic approaches towards the spirocyclic core structure of this natural product from readily available 2-phenylfurans. Although initial studies involving an oxidative cyclization were unsuccessful,
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Phelligridin G is an unusual natural product that contains an embedded spiro-fused furanone core. We have investigated two furan-based synthetic approaches towards the spirocyclic core structure of this natural product from readily available 2-phenylfurans. Although initial studies involving an oxidative cyclization were unsuccessful, we were ultimately able to access this key system through a sequential intermolecular furan Diels-Alder reaction followed by a metathesis-based reorganization. A related approach led to an expanded C ring to form spiro-fused pyran spirocycles. Full article
(This article belongs to the Special Issue Spiro Compounds)
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Open AccessArticle Sonolytic and Silent Polymerization of Methacrlyic Acid Butyl Ester Catalyzed by a New Onium Salt with bis-Active Sites in a Biphasic System — A Comparative Investigation
Molecules 2013, 18(2), 2419-2437; https://doi.org/10.3390/molecules18022419
Received: 22 November 2012 / Revised: 9 January 2013 / Accepted: 28 January 2013 / Published: 21 February 2013
Cited by 8 | PDF Full-text (256 KB) | HTML Full-text | XML Full-text
Abstract
Currently, ingenious new analytical and process experimental techniques which are environmentally benign techniques, viz., ultrasound irradiation, have become immensely popular in promoting various reactions. In this work, a novel soluble multi-site phase transfer catalyst (PTC) viz., 1,4-bis-(propylmethyleneammounium chloride)benzene (BPMACB) was synthesized
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Currently, ingenious new analytical and process experimental techniques which are environmentally benign techniques, viz., ultrasound irradiation, have become immensely popular in promoting various reactions. In this work, a novel soluble multi-site phase transfer catalyst (PTC) viz., 1,4-bis-(propylmethyleneammounium chloride)benzene (BPMACB) was synthesized and its catalytic efficiency was assessed by observing the kinetics of sonolytic polymerization of methacrylic acid butyl ester (MABE) using potassium persulphate (PPS) as an initiator. The ultrasound–multi-site phase transfer catalysis (US-MPTC)-assisted polymerization reaction was compared with the silent (non-ultrasonic) polymerization reaction. The effects of the catalyst and various reaction parameters on the catalytic performance were in detail investigated by following the kinetics of polymerization of MABE in an ethyl acetate-water biphasic system. From the detailed kinetic investigation we propose a plausible mechanism. Further the kinetic results demonstrate clearly that ultrasound-assisted phase-transfer catalysis significantly increased the reaction rate when compared to silent reactions. Notably, this environmentally benign and cost-effective process has great potential to be applied in various polymer industries. Full article
(This article belongs to the Special Issue Phase Transfer Catalysis)
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Open AccessArticle 7-Methoxytacrine-Adamantylamine Heterodimers as Cholinesterase Inhibitors in Alzheimer’s Disease Treatment — Synthesis, Biological Evaluation and Molecular Modeling Studies
Molecules 2013, 18(2), 2397-2418; https://doi.org/10.3390/molecules18022397
Received: 14 January 2013 / Revised: 24 January 2013 / Accepted: 4 February 2013 / Published: 20 February 2013
Cited by 36 | PDF Full-text (510 KB) | HTML Full-text | XML Full-text
Abstract
A structural series of 7-MEOTA-adamantylamine thioureas was designed, synthesized and evaluated as inhibitors of human acetylcholinesterase (hAChE) and human butyrylcholinesterase (hBChE). The compounds were prepared based on the multi-target-directed ligand strategy with different linker lengths (n = 2–8) joining the well-known NMDA antagonist
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A structural series of 7-MEOTA-adamantylamine thioureas was designed, synthesized and evaluated as inhibitors of human acetylcholinesterase (hAChE) and human butyrylcholinesterase (hBChE). The compounds were prepared based on the multi-target-directed ligand strategy with different linker lengths (n = 2–8) joining the well-known NMDA antagonist adamantine and the hAChE inhibitor 7-methoxytacrine (7-MEOTA). Based on in silico studies, these inhibitors proved dual binding site character capable of simultaneous interaction with the peripheral anionic site (PAS) of hAChE and the catalytic active site (CAS). Clearly, these structural derivatives exhibited very good inhibitory activity towards hBChE resulting in more selective inhibitors of this enzyme. The most potent cholinesterase inhibitor was found to be thiourea analogue 14 (with an IC50 value of 0.47 µM for hAChE and an IC50 value of 0.11 µM for hBChE, respectively). Molecule 14 is a suitable novel lead compound for further evaluation proving that the strategy of dual binding site inhibitors might be a promising direction for development of novel AD drugs. Full article
(This article belongs to the Section Medicinal Chemistry)
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Open AccessArticle Synthesis and Crystal Structures of N-Substituted Pyrazolines
Molecules 2013, 18(2), 2386-2396; https://doi.org/10.3390/molecules18022386
Received: 12 December 2012 / Revised: 2 February 2013 / Accepted: 7 February 2013 / Published: 20 February 2013
Cited by 3 | PDF Full-text (821 KB) | HTML Full-text | XML Full-text
Abstract
Four pyrazole compounds, 3-(4-fluorophenyl)-5-phenyl-4,5-dihydro-1H-pyrazole-1-carbaldehyde (1), 5-(4-bromophenyl)-3-(4-fluorophenyl)-4,5-dihydro-1H-pyrazole-1-carbaldehyde (2), 1-[5-(4-chlorophenyl)-3-(4-fluorophenyl)-4,5-dihydro-1H-pyrazol-1-yl]ethanone (3) and 1-[3-(4-fluorophenyl)-5-phenyl-4,5-dihydro-1H-pyrazol-1-yl]propan-1-one (4), have been prepared by condensing chalcones with hydrazine hydrate in the presence of aliphatic acids,
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Four pyrazole compounds, 3-(4-fluorophenyl)-5-phenyl-4,5-dihydro-1H-pyrazole-1-carbaldehyde (1), 5-(4-bromophenyl)-3-(4-fluorophenyl)-4,5-dihydro-1H-pyrazole-1-carbaldehyde (2), 1-[5-(4-chlorophenyl)-3-(4-fluorophenyl)-4,5-dihydro-1H-pyrazol-1-yl]ethanone (3) and 1-[3-(4-fluorophenyl)-5-phenyl-4,5-dihydro-1H-pyrazol-1-yl]propan-1-one (4), have been prepared by condensing chalcones with hydrazine hydrate in the presence of aliphatic acids, namely formic acid, acetic acid and propionic acid. The structures were characterized by X-ray single crystal structure determination. The dihedral angles formed between the pyrazole and the fluoro-substituted rings are 4.64(7)° in 1, 5.3(4)° in 2 and 4.89(6)° in 3. In 4, the corresponding angles for molecules A and molecules B are 10.53(10)° and 9.78(10)°, respectively. Full article
(This article belongs to the Section Organic Chemistry)
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Open AccessArticle Free Radical Scavenging Activity of Kielmeyera variabilis (Clusiaceae)
Molecules 2013, 18(2), 2376-2385; https://doi.org/10.3390/molecules18022376
Received: 7 January 2013 / Revised: 1 February 2013 / Accepted: 1 February 2013 / Published: 19 February 2013
Cited by 14 | PDF Full-text (237 KB) | HTML Full-text | XML Full-text
Abstract
As part of our ongoing research on antioxidant agents from Brazilian flora, we screened the free radical scavenging activity of two extracts and eight fractions of Kielmeyera variabilis (Clusiaceae) using DPPH· (2,2-diphenyl-1-picrylhydrazyl-hydrate) and ABTS·+ [2,2'-azinobis(3-ethylenebenzothiazoline-6-sulfonic acid)] colorimetric assays. The ethyl
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As part of our ongoing research on antioxidant agents from Brazilian flora, we screened the free radical scavenging activity of two extracts and eight fractions of Kielmeyera variabilis (Clusiaceae) using DPPH· (2,2-diphenyl-1-picrylhydrazyl-hydrate) and ABTS·+ [2,2'-azinobis(3-ethylenebenzothiazoline-6-sulfonic acid)] colorimetric assays. The ethyl acetate and n-butanol fractions of the leaves of K. variabilis displayed the strongest activity (IC50 of 3.5 ± 0.3 and 4.4 ± 0.2 μg mL−1 for DPPH· and 6.6 ± 0.4 and 3.1 ± 0.1 μg mL−1 for ABTS·+, respectively). Chromatographic fractionation of the most potent fractions led to identification of three flavonols with previously described antioxidant activity, quercitrin (1), quercetin-3-O-b-glucoside (3), and quercetin-3-O-b-galactoside (4), and of one biflavone, podocarpusflavone A (2). This is the first time that the presence of these flavonoids in Kielmeyera variabilis has been reported. Full article
(This article belongs to the Section Natural Products Chemistry)
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Open AccessReview Techniques for Analysis of Plant Phenolic Compounds
Molecules 2013, 18(2), 2328-2375; https://doi.org/10.3390/molecules18022328
Received: 25 October 2012 / Revised: 10 January 2013 / Accepted: 31 January 2013 / Published: 19 February 2013
Cited by 245 | PDF Full-text (600 KB) | HTML Full-text | XML Full-text
Abstract
Phenolic compounds are well-known phytochemicals found in all plants. They consist of simple phenols, benzoic and cinnamic acid, coumarins, tannins, lignins, lignans and flavonoids. Substantial developments in research focused on the extraction, identification and quantification of phenolic compounds as medicinal and/or dietary molecules
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Phenolic compounds are well-known phytochemicals found in all plants. They consist of simple phenols, benzoic and cinnamic acid, coumarins, tannins, lignins, lignans and flavonoids. Substantial developments in research focused on the extraction, identification and quantification of phenolic compounds as medicinal and/or dietary molecules have occurred over the last 25 years. Organic solvent extraction is the main method used to extract phenolics. Chemical procedures are used to detect the presence of total phenolics, while spectrophotometric and chromatographic techniques are utilized to identify and quantify individual phenolic compounds. This review addresses the application of different methodologies utilized in the analysis of phenolic compounds in plant-based products, including recent technical developments in the quantification of phenolics. Full article
(This article belongs to the Special Issue Methods in Polyphenol Analysis)
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Open AccessReview 3-Substituted Prolines: From Synthesis to Structural Applications, from Peptides to Foldamers
Molecules 2013, 18(2), 2307-2327; https://doi.org/10.3390/molecules18022307
Received: 1 February 2013 / Revised: 5 February 2013 / Accepted: 6 February 2013 / Published: 19 February 2013
Cited by 23 | PDF Full-text (1038 KB) | HTML Full-text | XML Full-text
Abstract
Among the twenty natural proteinogenic amino acids, proline is unique as its secondary amine forms a tertiary amide when incorporated into biopolymers, thus preventing hydrogen bond formation. Despite the lack of hydrogen bonds and thanks to conformational restriction of flexibility linked to the
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Among the twenty natural proteinogenic amino acids, proline is unique as its secondary amine forms a tertiary amide when incorporated into biopolymers, thus preventing hydrogen bond formation. Despite the lack of hydrogen bonds and thanks to conformational restriction of flexibility linked to the pyrrolidine ring, proline is able to stabilize peptide secondary structures such as b-turns or polyproline helices. These unique conformational properties have aroused a great interest in the development of proline analogues. Among them, proline chimeras are tools combining the proline restriction of flexibility together with the information brought by natural amino acids side chains. This review will focus on the chemical syntheses of 3-substituted proline chimeras of potential use for peptide syntheses and as potential use as tools for SAR studies of biologically active peptides and the development of secondary structure mimetics. Their influence on peptide structure will be briefly described. Full article
(This article belongs to the Special Issue Chemical Protein and Peptide Synthesis)
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Open AccessArticle Neglschisandrins E–F: Two New Lignans and Related Cytotoxic Lignans from Schisandra neglecta
Molecules 2013, 18(2), 2297-2306; https://doi.org/10.3390/molecules18022297
Received: 13 December 2012 / Revised: 30 January 2013 / Accepted: 31 January 2013 / Published: 19 February 2013
Cited by 8 | PDF Full-text (364 KB) | HTML Full-text | XML Full-text
Abstract
Phytochemical investigation of an ethanolic extract of stems of Schisandra neglecta led to the isolation and identification of two new dibenzocyclooctadiene lignans, designated neglschisandrins E (1) and F (2), and thirteen known lignans. All structures and stereochemistries were determined
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Phytochemical investigation of an ethanolic extract of stems of Schisandra neglecta led to the isolation and identification of two new dibenzocyclooctadiene lignans, designated neglschisandrins E (1) and F (2), and thirteen known lignans. All structures and stereochemistries were determined by spectroscopic methods, including 2D-NMR techniques. The isolates were evaluated for in vitro cytotoxic activity. Among them, compounds 26 exhibited moderate to weak cytotoxicity against the human colorectal carcinoma HCT-8 cell line with EC50 values of 7.33~19.8 μg/mL. In addition, compounds 24 also exhibited marginal cytotoxicity against the human lung carcinoma A549 cell line with EC50 values of 11.8~15.0 μg/mL. Full article
(This article belongs to the Section Natural Products Chemistry)
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Open AccessArticle Enthalpy/Entropy Contributions to Conformational KIEs: Theoretical Predictions and Comparison with Experiment
Molecules 2013, 18(2), 2281-2296; https://doi.org/10.3390/molecules18022281
Received: 4 December 2012 / Revised: 22 January 2013 / Accepted: 1 February 2013 / Published: 18 February 2013
Cited by 2 | PDF Full-text (530 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Previous theoretical studies of Mislow’s doubly-bridged biphenyl ketone 1 and dihydrodimethylphenanthrene 2 have determined significant entropic contributions to their normal (1) and inverse (2) conformational kinetic isotope effects (CKIEs). To broaden our investigation, we have used density functional methods
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Previous theoretical studies of Mislow’s doubly-bridged biphenyl ketone 1 and dihydrodimethylphenanthrene 2 have determined significant entropic contributions to their normal (1) and inverse (2) conformational kinetic isotope effects (CKIEs). To broaden our investigation, we have used density functional methods to characterize the potential energy surfaces and vibrational frequencies for ground and transition structures of additional systems with measured CKIEs, including [2.2]-metaparacyclophane-d (3), 1,1'-binaphthyl (4), 2,2'-dibromo-[1,1'-biphenyl]-4,4'-dicarboxylic acid (5), and the 2-(N,N,N-trimethyl)-2'-(N,N-dimethyl)-diaminobiphenyl cation (6). We have also computed CKIEs in a number of systems whose experimental CKIEs are unknown. These include analogs of 1 in which the C=O groups have been replaced with CH2 (7), O (8), and S (9) atoms and ring-expanded variants of 2 containing CH2 (10), O (11), S (12), or C=O (13) groups. Vibrational entropy contributes to the CKIEs in all of these systems with the exception of cyclophane 3, whose isotope effect is predicted to be purely enthalpic in origin and whose Bigeleisen-Mayer ZPE term is equivalent to ΔΔ H. There is variable correspondence between these terms in the other molecules studied, thus identifying additional examples of systems in which the Bigeleisen-Mayer formalism does not correlate with ΔHS dissections. Full article
(This article belongs to the Special Issue Isotope Effects)
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Open AccessArticle Quenching of Tryptophan Fluorescence in the Presence of 2,4-DNP, 2,6-DNP, 2,4-DNA and DNOC and Their Mechanism of Toxicity
Molecules 2013, 18(2), 2266-2280; https://doi.org/10.3390/molecules18022266
Received: 4 January 2013 / Revised: 6 February 2013 / Accepted: 13 February 2013 / Published: 18 February 2013
Cited by 8 | PDF Full-text (493 KB) | HTML Full-text | XML Full-text
Abstract
Although they are widely used as insecticides, acaricides and fungicides in the agriculture or as raw materials in the dye industry, dinitrophenols (DNPs) are extremely noxious, death cases having been registered. These compounds produce cataracts, lower leucocyte levels, disturb the general metabolism and
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Although they are widely used as insecticides, acaricides and fungicides in the agriculture or as raw materials in the dye industry, dinitrophenols (DNPs) are extremely noxious, death cases having been registered. These compounds produce cataracts, lower leucocyte levels, disturb the general metabolism and can cause cancer. It is also assumed that DNPs hinder the proton translocation through the mitochondrial inner membrane and therefore inhibit oxidative phosphorylation. Their fluorescence quenching properties can help understand and explain their toxicity. Fluorescence quenching of tryptophan was tested using different dinitrophenols such as 2,4-dinitrophenol (2,4-DNP), 4,6-dinitro-orthocresol (DNOC), 2-[(2,4-dinitrophenyl)amino]acetic acid (GlyDNP), 2-(1-methyl-heptyl)-4.6-dinitrophenyl crotonate (Karathan), 2-amino-5-[(1-((carboxymethyl)amino)-3-((2,4-dinitrophenyl)thio)-1-oxopropan-2-yl)amino]-5-oxopentanoic acid (SDN GSH), 2,4-dinitroanisole (2,4-DNA) and 2,4-dinitrobenzoic acid (2,4-DNB). 2,4-DNP and DNOC showed the highest tryptophan fluorescence quenching constant values, these being also the most toxic compounds. The electronic chemical potential value of the most stable complex of 2,4-DNP-with tryptophan is higher than the values of the electronic chemical potentials of complexes corresponding to the derivatives. Full article
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Open AccessArticle Characterization of Proanthocyanidins in Stems of Polygonum multiflorum Thunb as Strong Starch Hydrolase Inhibitors
Molecules 2013, 18(2), 2255-2265; https://doi.org/10.3390/molecules18022255
Received: 10 December 2012 / Revised: 5 February 2013 / Accepted: 5 February 2013 / Published: 18 February 2013
Cited by 12 | PDF Full-text (385 KB) | HTML Full-text | XML Full-text
Abstract
Characterzation of polyphenolic compounds in the stems of P. multiflorum was conducted using HPLC, high resolution LC-MS and LC-MSn. Proanthocyanidins in particular were isolated in 4.8% yield using solvent extraction followed by Sephadex LH-20 fractionation. HPLC analysis using a diol column
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Characterzation of polyphenolic compounds in the stems of P. multiflorum was conducted using HPLC, high resolution LC-MS and LC-MSn. Proanthocyanidins in particular were isolated in 4.8% yield using solvent extraction followed by Sephadex LH-20 fractionation. HPLC analysis using a diol column revealed oligomers (from dimer to nonamer) as minor components, with (epi)catechin monomeric units predominating, and oligomers with higher degree of polymerization being dominant. Thiolysis treatment of the proanthocyanidins using mercaptoacetic acid produced thioether derivatives of (epi)catechin as the major product and a mean value of the degree of polymerization of 32.6 was estimated from the ratio of terminal and extension units of the (epi)catechin. The isolated proanthocyanidins were shown to strongly inhibit α-amylase with an acarbose equivalence (AE) value of 1,954.7 µmol AE/g and inhibit α-glucosidase with an AE value of 211.1 µmol AE/g. Full article
(This article belongs to the Section Natural Products Chemistry)
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Open AccessArticle Growth of Fullerene Fragments Using the Diels-Alder Cycloaddition Reaction: First Step towards a C60 Synthesis by Dimerization
Molecules 2013, 18(2), 2243-2254; https://doi.org/10.3390/molecules18022243
Received: 25 December 2012 / Revised: 20 January 2013 / Accepted: 5 February 2013 / Published: 13 February 2013
Cited by 4 | PDF Full-text (576 KB)
Abstract
Density Functional Theory has been used to model the Diels-Alder reactions of the fullerene fragments triindenetriphenilene and pentacyclopentacorannulene with ethylene and 1,3-butadiene. The purpose is to prove the feasibility of using Diels-Alder cycloaddition reactions to grow fullerene fragments step by step, and to
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Density Functional Theory has been used to model the Diels-Alder reactions of the fullerene fragments triindenetriphenilene and pentacyclopentacorannulene with ethylene and 1,3-butadiene. The purpose is to prove the feasibility of using Diels-Alder cycloaddition reactions to grow fullerene fragments step by step, and to dimerize fullerene fragments, as a way to obtain C60. The dienophile character of the fullerene fragments is dominant, and the reaction of butadiene with pentacyclopentacorannulene is favored. Full article
(This article belongs to the Special Issue Diels-Alder Reaction)
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Open AccessArticle New Spiral γ-Lactone Enantiomers from the Plant Endophytic Fungus Pestalotiopsis foedan
Molecules 2013, 18(2), 2236-2242; https://doi.org/10.3390/molecules18022236
Received: 27 December 2012 / Revised: 20 January 2013 / Accepted: 22 January 2013 / Published: 11 February 2013
Cited by 7 | PDF Full-text (285 KB) | Supplementary Files
Abstract
(−)-(4S, 8S)-Foedanolide (1a) and (+)-(4R, 8R)-foedanolide (1b), a pair of new spiro-γ-lactone enantiomers, were isolated from the fermentation broth of the plant endophytic fungus Pestalotiopsis foedan by HPLC using a chiral
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(−)-(4S, 8S)-Foedanolide (1a) and (+)-(4R, 8R)-foedanolide (1b), a pair of new spiro-γ-lactone enantiomers, were isolated from the fermentation broth of the plant endophytic fungus Pestalotiopsis foedan by HPLC using a chiral column, achieving over 7% ee. Their structures and absolute configurations were determined on the basis of extensive analysis of NMR spectra combined with computational methods via calculation of the electronic circular dichroism (ECD) and optical rotation (OR). Compounds 1a and 1b showed moderate activities against HeLa, A-549, U-251, HepG2 and MCF-7 tumor cell lines. Full article
(This article belongs to the Section Natural Products Chemistry)
Open AccessArticle Preparation of an Immunoaffinity Column with Amino-Silica Gel Microparticles and Its Application in Sample Cleanup for Aflatoxin Detection in Agri-Products
Molecules 2013, 18(2), 2222-2235; https://doi.org/10.3390/molecules18022222
Received: 13 December 2012 / Revised: 24 January 2013 / Accepted: 28 January 2013 / Published: 11 February 2013
Cited by 19 | PDF Full-text (451 KB)
Abstract
This study established an immunoaffinity column for selective extraction of aflatoxins in agri-products. Specifically, the immunoaffinity column was developed by covalently coupling monoclonal antibody 1C11 against aflatoxins to amino-silica gel microparticles and then packing these into a cartridge. The extraction conditions were thoroughly
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This study established an immunoaffinity column for selective extraction of aflatoxins in agri-products. Specifically, the immunoaffinity column was developed by covalently coupling monoclonal antibody 1C11 against aflatoxins to amino-silica gel microparticles and then packing these into a cartridge. The extraction conditions were thoroughly optimized in terms of loading, washing and eluting solutions. Under the optimal conditions, the immunoaffinity column had a capacity of 200 ng of aflatoxins. The detection limits (S/N = 3) for aflatoxin G1, B1, G2 and B2 were 0.03, 0.07, 0.05 and 0.09 μg·kg−1, and the corresponding quantification limits (S/N = 10) were 0.10, 0.25, 0.18 and 0.30 μg·kg−1, respectively. The recoveries of aflatoxins in samples were 90.1%–104.4% and RSDs were <4.4%. The developed method was further applied to the determination of aflatoxins in peanut, vegetable oil and tea samples, and the results indicated that peanut (26.9%), vegetable oils (28.0%) and tea (5.3%) samples were contaminated with aflatoxins, with levels ranging from 0.49 to 20.79 μg·kg−1. Full article
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