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Molecules, Volume 13, Issue 4 (April 2008), Pages 716-1024

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Open AccessArticle An Efficient Synthesis of γ-Aminoacids and Attempts to Drive Its Enantioselectivity
Molecules 2008, 13(4), 716-728; doi:10.3390/molecules13040716
Received: 10 March 2008 / Revised: 26 March 2008 / Accepted: 26 March 2008 / Published: 27 March 2008
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Abstract
Addition of carboxylic acid dianions to bromoacetonitrile lead, in good yields,to the corresponding γ-cyanoacids, which on hydrogenation yielded γ-aminoacids. Thistwo step methodology improves upon previously described results. Poor e.e’s resultedfrom our attempts to drive the enantioselectivity of this transformation by chiral amideinduction. [...] Read more.
Addition of carboxylic acid dianions to bromoacetonitrile lead, in good yields,to the corresponding γ-cyanoacids, which on hydrogenation yielded γ-aminoacids. Thistwo step methodology improves upon previously described results. Poor e.e’s resultedfrom our attempts to drive the enantioselectivity of this transformation by chiral amideinduction. Full article
Open AccessArticle Three New Caffeoyl Glycosides from the Roots of Picrorhiza Scrophulariiflora
Molecules 2008, 13(4), 729-735; doi:10.3390/molecules13040729
Received: 2 February 2008 / Accepted: 24 March 2008 / Published: 27 March 2008
Cited by 9 | PDF Full-text (161 KB) | HTML Full-text | XML Full-text
Abstract
From the underground parts of Picrorhiza scrophulariiflora, three new caffeoylglycosides, scrocaffeside A-C (1-3), together with two caffeic acid derivates, 4-O-β-Dglucopyranosylcaffeic acid (4) and 4-methoxycaffeic acid (5) and a phenylethanoidglycoside, scroside D (6), were isolated. Their structures were elucidated on the basis ofchemical [...] Read more.
From the underground parts of Picrorhiza scrophulariiflora, three new caffeoylglycosides, scrocaffeside A-C (1-3), together with two caffeic acid derivates, 4-O-β-Dglucopyranosylcaffeic acid (4) and 4-methoxycaffeic acid (5) and a phenylethanoidglycoside, scroside D (6), were isolated. Their structures were elucidated on the basis ofchemical and spectroscopic evidence and comparisons with literature data of relatedcompounds. Full article
Open AccessArticle Comparative Studies on Conventional and Microwave Synthesis of Some Benzimidazole, Benzothiazole and Indole Derivatives and Testing on Inhibition of Hyaluronidase
Molecules 2008, 13(4), 736-748; doi:10.3390/molecules13040736
Received: 12 February 2008 / Revised: 20 March 2008 / Accepted: 20 March 2008 / Published: 27 March 2008
Cited by 41 | PDF Full-text (178 KB) | HTML Full-text | XML Full-text
Abstract
We have synthesized twelve 2-substituted benzimidazole, benzothiazole andindole derivatives using on both microwave irradiation and conventional heating methods.The microwave method was observed to be more beneficial as it provides an increase ofyield from 3% to 113% and a 95 to 98 % [...] Read more.
We have synthesized twelve 2-substituted benzimidazole, benzothiazole andindole derivatives using on both microwave irradiation and conventional heating methods.The microwave method was observed to be more beneficial as it provides an increase ofyield from 3% to 113% and a 95 to 98 % reduction in time. All compounds were tested bya stains-all assay at pH 7 and by a Morgan-Elson assay at pH 3.5 for hyaluronidaseinhibitory activity at a concentration of 100 μM. The most potent compound was 2-(4-hydroxyphenyl)-3-phenylindole (12) with an IC50 value of 107 μM at both pH 7 and 3.5. Full article
Open AccessArticle Antioxidant Activity of Diphenylpropionamide Derivatives: Synthesis, Biological Evaluation and Computational Analysis
Molecules 2008, 13(4), 749-761; doi:10.3390/molecules13040749
Received: 14 February 2008 / Revised: 4 March 2008 / Accepted: 25 March 2008 / Published: 28 March 2008
Cited by 3 | PDF Full-text (211 KB) | HTML Full-text | XML Full-text
Abstract
We report the synthesis, antioxidant and antiproliferative activity and a QSARanalysis of synthetic diphenylpropionamide derivatives. Synthesis of these compounds wasachieved by direct condensation of 2,2- and 3,3-diphenylpropionic acid and appropriateamines using 1-propylphoshonic acid cyclic anhydride (PPAA) as catalyst. Compoundstructures were elucidated by [...] Read more.
We report the synthesis, antioxidant and antiproliferative activity and a QSARanalysis of synthetic diphenylpropionamide derivatives. Synthesis of these compounds wasachieved by direct condensation of 2,2- and 3,3-diphenylpropionic acid and appropriateamines using 1-propylphoshonic acid cyclic anhydride (PPAA) as catalyst. Compoundstructures were elucidated by NMR analysis and their melting points were measured. Thein vitro antioxidant activity of these compounds was tested by evaluating the amount ofscavenged ABTS radical and estimating ROS and NO production in LPS stimulatedJ774.A1 macrophages. All compounds were tested for their effect on viability of cells andresults demonstrated that they are not toxic towards the cell lines used. The cytotoxicactivity of all compounds was evaluated by a Brine Shrimp Test. Full article
Open AccessCommunication Novel Unsaturated Sucrose Ethers and Their Application as Monomers
Molecules 2008, 13(4), 762-770; doi:10.3390/molecules13040762
Received: 5 March 2008 / Revised: 26 March 2008 / Accepted: 26 March 2008 / Published: 28 March 2008
Cited by 10 | PDF Full-text (141 KB) | HTML Full-text | XML Full-text
Abstract
Novel unsaturated ethers were synthesised in good yields starting from sucrose,using a two-step mild and efficient procedure based on the Gassman method, whichconsists in forming a vinyl group by the elimination of ethanol from mixed acetals withtrimethylsilyl trifluoromethanesulfonate in the presence of [...] Read more.
Novel unsaturated ethers were synthesised in good yields starting from sucrose,using a two-step mild and efficient procedure based on the Gassman method, whichconsists in forming a vinyl group by the elimination of ethanol from mixed acetals withtrimethylsilyl trifluoromethanesulfonate in the presence of alkyl amines. Mixed acetals arereadily obtained from the corresponding alcohols and ethyl vinyl ether, using an acidiccatalyst. Conventional etherification involving a primary halide was also examined. Themonomers thus obtained were successfully polymerised by a free radical mechanism,yielding unbranched linear and soluble polymers with pending sucrose moieties, and someof their physical properties were determined. Full article
Open AccessArticle Marine Bifunctional Sphingolipids from the Sponge Oceanapia ramsayi
Molecules 2008, 13(4), 772-778; doi:10.3390/molecules13040772
Received: 6 February 2008 / Revised: 31 March 2008 / Accepted: 31 March 2008 / Published: 1 April 2008
Cited by 3 | PDF Full-text (160 KB) | HTML Full-text | XML Full-text
Abstract
During the course of our continuing studies on marine natural lipid products,two known sphingolipids have been isolated for the first time from a specimen of themarine sponge Oceanapia ramsayi collected at Itampolo on the west coast of Madagascarin the Indian Ocean. The [...] Read more.
During the course of our continuing studies on marine natural lipid products,two known sphingolipids have been isolated for the first time from a specimen of themarine sponge Oceanapia ramsayi collected at Itampolo on the west coast of Madagascarin the Indian Ocean. The structures were elucidated using NMR data and by comparisonwith literature data. The occurrence of these sphingolipids within other Oceanapia spp. isdiscussed. Full article
Open AccessArticle A Microwave-Assisted and Heteropolyacids-Catalysed Cyclocondensation Reaction for the Synthesis of 4(3H)-Quinazolinones
Molecules 2008, 13(4), 779-789; doi:10.3390/molecules13040779
Received: 6 February 2008 / Revised: 28 March 2008 / Accepted: 28 March 2008 / Published: 3 April 2008
Cited by 28 | PDF Full-text (160 KB) | HTML Full-text | XML Full-text
Abstract
We have investigated a microwave–assisted synthesis of 4(3H)–quinazolinonesby condensation of anthranilic acid, orthoesters (or formic acid) and substituted anilines,using Keggin-type heteropolyacids (H3PW12O40·13H2O, H4SiW12O40·13H2O,H4SiMo12 [...] Read more.
We have investigated a microwave–assisted synthesis of 4(3H)–quinazolinonesby condensation of anthranilic acid, orthoesters (or formic acid) and substituted anilines,using Keggin-type heteropolyacids (H3PW12O40·13H2O, H4SiW12O40·13H2O,H4SiMo12O40·13H2O or H3PMo12O40·13H2O) as catalysts. We found that the the use of H3PW12O40·13H2O acid coupled to microwave irradiation allows a solvent-free, rapid (~ 13min) and high-yielding reaction. Full article
Open AccessCommunication Antimicrobial Activity of Three Baccharis Species Used in the Traditional Medicine of Northern Chile
Molecules 2008, 13(4), 790-794; doi:10.3390/molecules13040790
Received: 31 January 2008 / Revised: 31 March 2008 / Accepted: 31 March 2008 / Published: 6 April 2008
Cited by 18 | PDF Full-text (41 KB) | HTML Full-text | XML Full-text
Abstract
The antimicrobial activities of aqueous ethanol and chloroform extracts of threeBaccharis species currently used in Northern Chile folk medicine for the treatment ofseveral infectious and inflammatory disorders were tested against Gram-positive andnegative bacteria and fungal spp. using the agar-disc diffusion assay. The [...] Read more.
The antimicrobial activities of aqueous ethanol and chloroform extracts of threeBaccharis species currently used in Northern Chile folk medicine for the treatment ofseveral infectious and inflammatory disorders were tested against Gram-positive andnegative bacteria and fungal spp. using the agar-disc diffusion assay. The results indicatedthat the activity was more pronounced against Gram-positive than against Gram-negativebacteria and yeast. No significant differences on the antibacterial activity were observed inthe aqueous ethanol versus chloroform extracts. None of the plant extracts evaluatedexhibited any activity against ten fungi tested. Full article
Open AccessArticle Contribution to the Analysis of the Essential Oil of Helichrysum italicum (Roth) G. Don. – Determination of Ester Bonded Acids and Phenols
Molecules 2008, 13(4), 795-803; doi:10.3390/molecules13040795
Received: 6 March 2008 / Revised: 3 April 2007 / Accepted: 3 April 2008 / Published: 7 April 2008
Cited by 11 | PDF Full-text (172 KB) | HTML Full-text | XML Full-text
Abstract
The essential oil of Helichrysum italicum (Roth) G. Don (everlasting orImmortelle essential oil) was isolated by hydrodistillation and analysed by GC and GCMS.Forty four compounds were identified. The main components were α-pinene(12.8%), 2-methyl-cyclohexyl pentanoate (11.1 %), neryl acetate (10.4%), 1,7-di-epi-α-cedrene (6.8%) and [...] Read more.
The essential oil of Helichrysum italicum (Roth) G. Don (everlasting orImmortelle essential oil) was isolated by hydrodistillation and analysed by GC and GCMS.Forty four compounds were identified. The main components were α-pinene(12.8%), 2-methyl-cyclohexyl pentanoate (11.1 %), neryl acetate (10.4%), 1,7-di-epi-α-cedrene (6.8%) and other compounds. The oil was fractionated and ester-containingfraction was hydrolysed with KOH/H2SO4. The liberated volatiles were analysed by GCand GC-MS: three phenols and twenty seven volatile carboxylic acids were identified[70% low fatty acids (C2-C5), 15% C10-C12 acids and 15% other acids]. The main acidswere acetic acid (24.3%) propanoic acid (17.2%), 2-methylpropanoic acid (11.4%),dodecanoic acid (8.7%), 2-methylbutanoic acid (8.3%), (Z)-2-methylbutenoic acid(5.1%) and decanoic acid (4.6%). With respect to the identified bonded carboxylic acids,the minimal number of esters in the oil was twenty seven, but their overall quantity wasprobably larger due to different possible combinations of alcohols with acids to formesters. On the other hand, only six main esters were identified in the oil beforefractionation and hydrolysis. Full article
Open AccessArticle Preparation of Zinc (II) and Cadmium (II) Complexes of the Tetradentate Schiff Base Ligand 2-((E)-(2-(2-(pyridine-2-yl)- ethylthio)ethylimino)methyl)-4-bromophenol (PytBrsalH)
Molecules 2008, 13(4), 804-811; doi:10.3390/molecules13040804
Received: 21 February 2008 / Revised: 2 April 2008 / Accepted: 6 April 2008 / Published: 8 April 2008
Cited by 21 | PDF Full-text (306 KB) | HTML Full-text | XML Full-text
Abstract
We describe the synthesis and characterization of two new zinc (II) andcadmium (II) complexes of the tetradentate dissymmetric Schiff base ligand 2-((E)-(2-(2-(pyridine-2-yl)ethylthio)ethylimino)methyl)-4-bromophenol (PytBrsalH), prepared from 1-(2-pyridyl)-3-thia-5-aminopentane (pyta) and 5-bromosalicylaldehyde. The complexeswere synthesized by treating an ethanolic solution of the ligand with equimolar [...] Read more.
We describe the synthesis and characterization of two new zinc (II) andcadmium (II) complexes of the tetradentate dissymmetric Schiff base ligand 2-((E)-(2-(2-(pyridine-2-yl)ethylthio)ethylimino)methyl)-4-bromophenol (PytBrsalH), prepared from 1-(2-pyridyl)-3-thia-5-aminopentane (pyta) and 5-bromosalicylaldehyde. The complexeswere synthesized by treating an ethanolic solution of the ligand with equimolar amounts ofappropriate metal salts in 1 M methanolic solution of NaOH or alternatively, by a moredirect route in which the two reactants are added to a solution of the ligand immediatelyafter formation of the latter and prior to any isolation. The complexes were characterizedby elemental analysis, FTIR, 1H-NMR, electronic spectra and molar conductivity.According to obtained data, the probable coordination geometries of zinc and cadmium inthese complexes with mixed N, S and O donor atoms are tetrahedral- and octahedral-like,respectively. Both complexes were found to be 1:1 electrolyte systems in acetonitrile. Full article
Open AccessArticle Variability of Two Essential Oils of Kundmannia sicula (L.) DC., A Traditional Algerian Medicinal Plant
Molecules 2008, 13(4), 812-817; doi:10.3390/molecules13040812
Received: 29 January 2008 / Revised: 27 March 2008 / Accepted: 27 March 2008 / Published: 8 April 2008
Cited by 10 | PDF Full-text (45 KB) | HTML Full-text | XML Full-text
Abstract
The essential oils of the aerial parts of Kundmannia sicula (L.) DC collectedfrom two Algerian localities, El Kala (near the coast) and Béjaia (from a meadow about 10km from the coast), were analysed by GC and GC-MS. Although both samples showedsimilar overall [...] Read more.
The essential oils of the aerial parts of Kundmannia sicula (L.) DC collectedfrom two Algerian localities, El Kala (near the coast) and Béjaia (from a meadow about 10km from the coast), were analysed by GC and GC-MS. Although both samples showedsimilar overall chemical compositions, the major components of the Béjaia sample wereidentified as being spathulenol (14.8%), caryophyllene oxide (12.2%), salvial-4(14)en-1-one (10.1%), 1,5-epoxysalvial-4(14)ene (5.2%) and germacrene D (3.2%), while in the ElKala sample the main compounds were found to be salvial-4(14)en-1-one (16.4%), 1,5-epoxysalvial-4(14)ene (6.5%), chrysanthenyl acetate (5.2%) and α-amorphene (2.9%). Full article
Open AccessArticle Synthesis of New N-Arylpyrimidin-2-amine Derivatives Using a Palladium Catalyst
Molecules 2008, 13(4), 818-830; doi:10.3390/molecules13040818
Received: 26 March 2008 / Revised: 8 April 2008 / Accepted: 8 April 2007 / Published: 9 April 2008
Cited by 6 | PDF Full-text (128 KB) | HTML Full-text | XML Full-text
Abstract
New N-aryl-4-(pyridin-3-yl)pyrimidin-2-amine derivatives were synthesizedfrom the corresponding amines, applying optimized Buchwald-Hartwig aminationconditions using dichlorobis(triphenylphosphine)Pd(II), xantphos and sodium tertbutoxidein refluxing toluene under a nitrogen atmosphere. The target N-aryl derivativeswere obtained in moderate to good yields ranging from 27% to 82%. The proceduredescribed could [...] Read more.
New N-aryl-4-(pyridin-3-yl)pyrimidin-2-amine derivatives were synthesizedfrom the corresponding amines, applying optimized Buchwald-Hartwig aminationconditions using dichlorobis(triphenylphosphine)Pd(II), xantphos and sodium tertbutoxidein refluxing toluene under a nitrogen atmosphere. The target N-aryl derivativeswere obtained in moderate to good yields ranging from 27% to 82%. The proceduredescribed could be widely employed for the preparation of new heterocyclic compounds.The structures of the new compounds were confirmed by FT-NMR, FT-IR and elementalanalysis. Full article
Open AccessArticle Simple and Efficient Microwave Assisted N-Alkylation of Isatin
Molecules 2008, 13(4), 831-840; doi:10.3390/molecules13040831
Received: 11 March 2008 / Revised: 9 April 2008 / Accepted: 9 April 2008 / Published: 10 April 2008
Cited by 33 | PDF Full-text (112 KB) | HTML Full-text | XML Full-text
Abstract
We present herein the results of microwave promoted N-alkylations of isatin (1)with different alkyl, benzyl and functionalized alkyl halides. Reactions were carried outunder different conditions, always employing methodologies compatible with MW assistedchemistry. Generation of isatin anion employing diverse bases and solvents or [...] Read more.
We present herein the results of microwave promoted N-alkylations of isatin (1)with different alkyl, benzyl and functionalized alkyl halides. Reactions were carried outunder different conditions, always employing methodologies compatible with MW assistedchemistry. Generation of isatin anion employing diverse bases and solvents or using thepreformed isatin sodium salt was tested. The best results were achieved using K2CO3 orCs2CO3 and a few drops of N,N-dimethylformamide or N-methyl-2-pyrrolidinone. Thesereactions present noteworthy advantages over those carried out employing conventionalheating. Full article
Open AccessArticle Synthesis and Total 1H- and 13C-NMR Assignment of Cephem Derivatives for Use in ADEPT Approaches
Molecules 2008, 13(4), 841-854; doi:10.3390/molecules13040841
Received: 12 March 2008 / Revised: 6 April 2008 / Accepted: 7 April 2007 / Published: 10 April 2008
Cited by 2 | PDF Full-text (130 KB) | HTML Full-text | XML Full-text
Abstract
We report the synthesis and total NMR characterization of 5-thia-1-azabicyclo-[4.2.0]oct-2-ene-2-carboxylic acid-3-[[[(4’’-nitrophenoxy)carbonyl]oxy]-methyl]-8-oxo-7-[(2-thienyloxoacetyl)amino]-diphenylmethyl ester-5-dioxide (5), a new cephalosporinderivative. This compound can be used as the carrier of a wide range of drugs containingan amino group. The preparation of the intermediate product, 5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid-3-[methyl 4-(6-methoxyquinolin-8-ylamino)pentylcarbamate]-8-oxo-7-[(2-thienyloxoacetyl)amino]-diphenylmethyl [...] Read more.
We report the synthesis and total NMR characterization of 5-thia-1-azabicyclo-[4.2.0]oct-2-ene-2-carboxylic acid-3-[[[(4’’-nitrophenoxy)carbonyl]oxy]-methyl]-8-oxo-7-[(2-thienyloxoacetyl)amino]-diphenylmethyl ester-5-dioxide (5), a new cephalosporinderivative. This compound can be used as the carrier of a wide range of drugs containingan amino group. The preparation of the intermediate product, 5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid-3-[methyl 4-(6-methoxyquinolin-8-ylamino)pentylcarbamate]-8-oxo-7-[(2-thienyloxoacetyl)amino]-diphenylmethyl ester-5-dioxide (6), as well as the synthesis of the antimalarial primaquine prodrug 5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid-3-[methyl 4-(6-methoxyquinolin-8-ylamino)pentylcarbamate]-8-oxo-7-[(2-thienyloxoacetyl)amino]- 5-dioxide (7) are alsodescribed, together with their total 1H- and 13C-NMR assignments. Full article
(This article belongs to the Special Issue Prodrugs)
Open AccessArticle Blue Organic Light-emitting Supramolecular Microfibers: The Self-assembly of a 1,2,4-Triazolo[1,5-a]pyrimidine Derivative
Molecules 2008, 13(4), 855-863; doi:10.3390/molecules13040855
Received: 6 March 2008 / Revised: 7 April 2008 / Accepted: 12 April 2008 / Published: 12 April 2008
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Abstract The design and synthesis of 5,7-dimethyl-1,2,4-triazolo[1,5-a]pyrimidine-2-thioaceto-(2-fluorobenzyl) hydrazone (TPTH), which self-assembled into supramolecularmicrofibers with blue organic light-emitting properties, is reported. This is the firstoccurrence of the molecular self-assembly of 1,2,4-triazolo[1,5-a]pyrimidine derivatives. Full article
Open AccessArticle Effects of Leucine-enkephalin on Catalase Activity and Hydrogen Peroxide Levels in the Haemolymph of the Pacific Oyster (Crassostrea gigas)
Molecules 2008, 13(4), 864-870; doi:10.3390/molecules13040864
Received: 21 March 2008 / Revised: 6 April 2008 / Accepted: 7 April 2008 / Published: 15 April 2008
Cited by 4 | PDF Full-text (169 KB) | HTML Full-text | XML Full-text
Abstract
The nervous and immune systems of invertebrates can exchange informationthrough neuropeptides. Furthermore, some opioid peptides can function as endogenousimmune system messengers and participate in the regulation of the immune responses. Thepresent study was designed to investigate the effects of leucine-enkephalin (L-ENK) on [...] Read more.
The nervous and immune systems of invertebrates can exchange informationthrough neuropeptides. Furthermore, some opioid peptides can function as endogenousimmune system messengers and participate in the regulation of the immune responses. Thepresent study was designed to investigate the effects of leucine-enkephalin (L-ENK) on theactivity of catalase (CAT) and hydrogen peroxide (H2O2) content in the haemolymph ofthe Pacific Oyster (Crassostrea gigas). The CAT activity and H2O2 content wereinvestigated after the haemolymph of the species was exposed to 1, 5, and 50 μg/mL of LENK.The results indicate that the intracellular and extracellular CAT activity wasincreased with increasing concentration of L-ENK, while the intracellular and extracellularH2O2 content was decreased with increasing concentration of L-ENK. L-ENK mayregulate the intracellular and extracellular CAT activity and H2O2 content via binding withopioid neuropeptide receptors on immunocytes of the oysters. The data strongly suggestsan involvement of opioid peptides in the regulation of the antioxidant defence systems ofCrassostrea gigas. Full article
Open AccessArticle Development of an Enzyme-linked Immuno-Sorbent Assay (ELISA) Method for Carbofuran Residues
Molecules 2008, 13(4), 871-881; doi:10.3390/molecules13040871
Received: 27 March 2008 / Revised: 14 April 2008 / Accepted: 14 April 2008 / Published: 17 April 2008
Cited by 9 | PDF Full-text (141 KB) | HTML Full-text | XML Full-text
Abstract
The haptens 4-[[(2,3-dihydro-2,2-dimethyl-7-benzofuranyloxy)carbonyl]-amino]butanoic acid (BFNB) and 6-[((2,3-dihydro-2,2-dimethyl-7-benzofuranyloxy)-carbonylamino]hexanoic acid (BFNH) were synthesized and then used to develop a rapid,specific and sensitive ELISA method to determine residues of the pesticide carbofuran in avariety of matrices. A hybridoma cell line (5D3) producing anti-carbofuran monoclonalantibodies (MAbs) [...] Read more.
The haptens 4-[[(2,3-dihydro-2,2-dimethyl-7-benzofuranyloxy)carbonyl]-amino]butanoic acid (BFNB) and 6-[((2,3-dihydro-2,2-dimethyl-7-benzofuranyloxy)-carbonylamino]hexanoic acid (BFNH) were synthesized and then used to develop a rapid,specific and sensitive ELISA method to determine residues of the pesticide carbofuran in avariety of matrices. A hybridoma cell line (5D3) producing anti-carbofuran monoclonalantibodies (MAbs) was also established. Based on the MAbs in combination with theheterologous hapten BFNH coupled to either horseradish peroxidase (HRP) or ovalbumin(OVA), four ELISAs (formats I-IV) for the quantification of carbofuran were developedand compared. Among them, the optimized format II (the conjugate-coated directcompetitive ELISA) showed the best characteristics, with an IC50 value of 18.49 ng/mL, alimit of detection of 0.11 ng/mL and the shortest assay time (1 h). This ELISA method wasthen applied to the determinations of carbofuran in environmental water, soil and foodsamples. The relative standard deviations (R.S.D.s) ranged from 1.8% to 21.3% and themean recoveries were 104.6%, 108.3%, 106.3% and 100.1% for water, soil, lettuce andcabbage, respectively. Thus, the ELISA method of format II exhibited the potential todevelop commercial ELISA kits for a rapid detection of carbofuran for human health andenvironmental safety. Full article
Open AccessArticle A Structure-Activity Study of Antibacterial Diterpenoids
Molecules 2008, 13(4), 882-891; doi:10.3390/molecules13040822
Received: 28 March 2008 / Revised: 16 April 2008 / Accepted: 17 April 2008 / Published: 17 April 2008
Cited by 51 | PDF Full-text (573 KB) | HTML Full-text | XML Full-text
Abstract
An analysis of the antibacterial activities of 15 terpenoids, eleven of which werepreviously described by us and four were extracted from the literature, suggested twostructural requirements for activity of these and related compounds: a hydrophobic moiety,consisting of a substituted decalin skeleton, and [...] Read more.
An analysis of the antibacterial activities of 15 terpenoids, eleven of which werepreviously described by us and four were extracted from the literature, suggested twostructural requirements for activity of these and related compounds: a hydrophobic moiety,consisting of a substituted decalin skeleton, and a hydrophilic region possessing onehydrogen-bond-donor group. These structural requirements are responsible for an optimalinsertion of these and related compounds into cell membranes, as suggested by the resultsof docking some of these compounds into a model phospholipid bilayer. Full article
Open AccessArticle Cytoprotective Efficacy of Amifostine Against Radiation- Induced Rectal Toxicity: Objective and Subjective Grading Scales for Radiomucositis
Molecules 2008, 13(4), 892-903; doi:10.3390/molecules13040892
Received: 1 February 2008 / Revised: 16 April 2008 / Accepted: 16 April 2007 / Published: 18 April 2008
Cited by 5 | PDF Full-text (103 KB) | HTML Full-text | XML Full-text
Abstract
Curative radiation therapy of pelvic malignancies, frequently results in doselimitingtoxicities such as serous, mucoid, or more rarely, bloody diarrhea. Several studieshave evaluated the cytoprotective effects of amifostine in preventing rectal mucositisassociated with radiation treatment. We searched Medline for published comparativestudies that evaluated [...] Read more.
Curative radiation therapy of pelvic malignancies, frequently results in doselimitingtoxicities such as serous, mucoid, or more rarely, bloody diarrhea. Several studieshave evaluated the cytoprotective effects of amifostine in preventing rectal mucositisassociated with radiation treatment. We searched Medline for published comparativestudies that evaluated the use of amifostine to reduce radiation-induced toxicity associatedwith pelvic irradiation. In ten studies there was an evidence-based cytoprotection (P less than 0.05)by amifostine. Although results are variable, current evidence suggests that amifostine mayhave a radioprotective effect in the rectal mucosa, particularly when administeredintrarectally. Significant improvements were seen in both symptomatic and objective(rectosigmoidoscopy) end points. There is a need to conduct well-designed clinical trialswith sufficient numbers of participants to confirm these findings together with a costbenefitstudy. Objective measurements using rectosigmoidoscopy are superior tosubjective measures such as WHO or RTOG/EORTC toxicity grading scales. Full article
(This article belongs to the Special Issue Prodrugs)
Open AccessArticle Antimicrobial and Antioxidative Activities of Bioactive Constituents from Hydnophytum formicarum Jack.
Molecules 2008, 13(4), 904-921; doi:10.3390/molecules13040904
Received: 1 April 2008 / Revised: 17 April 2008 / Accepted: 17 April 2008 / Published: 18 April 2008
Cited by 57 | PDF Full-text (201 KB) | HTML Full-text | XML Full-text
Abstract
Hydnophytum formicarum Jack. (Rubiaceae) is a medicinal plant whose tuberspossesses cardiovascular, anti-inflammatory and antiparasitic effects and have been usedfor the treatment of hepatitis, rheumatism and diarrhea. Herein we report the isolation of itsactive constituents and the testing of their antimicrobial activity against [...] Read more.
Hydnophytum formicarum Jack. (Rubiaceae) is a medicinal plant whose tuberspossesses cardiovascular, anti-inflammatory and antiparasitic effects and have been usedfor the treatment of hepatitis, rheumatism and diarrhea. Herein we report the isolation of itsactive constituents and the testing of their antimicrobial activity against 27 strains ofmicroorganisms using an agar dilution method and of their antioxidative activity using theDPPH and SOD assays. The results show that the crude hexane, dichloromethane, ethylacetate and methanol extracts exert such activities. Particularly, the crude ethyl acetateextract exhibits antigrowth activity against many Gram-positive and Gram-negativebacteria with MIC 256 μg/mL. Shewanella putrefaciens ATCC 8671 is completelyinhibited at a lower MIC (128 μg/mL). Interestingly, Corynebacterium diphtheriae NCTC10356 is inhibited by all the tested extracts. Significantly, the ethyl acetate extract is alsothe most potent antioxidant, showing 83.31% radical scavenging activity with IC50 8.40μg/mL in the DPPH assay. The other extracts display weak to moderate antioxidativeMolecules 2008, 13905activities, ranging from 28.60-56.80% radical scavenging. The SOD assay shows thatmethanol extract exhibits the highest activity (74.19% inhibition of superoxide radical).The dichloromethane and ethyl acetate extracts display comparable SOD activity. Thepromising bioactivities of the crude ethyl acetate extract guided the first isolation ofbioactive flavonoid and phenolic compounds: isoliquiritigenin (2), protocatechualdehyde(3), butin (4) and butein (5) from this species. Their structures have been fully establishedby 1D and 2D NMR. In addition, stigmasterol was isolated from the crude hexane anddichloromethane extracts. The antimicrobial and cytotoxic activities of compounds 3-5were evaluated. The tested compounds were inactive against HuCCA-1 and KB cell lines,showing ED50> 10 μg/mL. Protocatechualdehyde (3) completely inhibits the growth ofPlesiomonas shigelloides with MIC ≤60 μg/mL. As a result, we propose that Hydnophytumformicarum Jack. can serve as a new source enriched with potent antioxidative andantimicrobial agents. Full article
Open AccessArticle Selective Dendritic Fluorescent Sensors for Zn(II)
Molecules 2008, 13(4), 922-930; doi:10.3390/molecules13040922
Received: 6 April 2008 / Revised: 17 April 2008 / Accepted: 18 April 2008 / Published: 19 April 2008
Cited by 11 | PDF Full-text (127 KB) | HTML Full-text | XML Full-text
Abstract
A series of dendritic 8-hydroxyquinoline (8-HQ) and 5-dialkyl(aryl)aminomethyl-8-HQ derivatives were synthesized and their fluoroionophoric properties towardrepresentative alkali, alkaline earth, group IIIA and transition metal ions wereinvestigated. Among the selected ions, Zn(II) enhanced the fluorescence of N-di-(methoxycarbonylethyl)aminoethyl-3-[4-(8-hydroxyquinolin-5-ylmethyl)piperazin-1-yl]-propanoic amide] (7) by 31-fold, while Al(III) [...] Read more.
A series of dendritic 8-hydroxyquinoline (8-HQ) and 5-dialkyl(aryl)aminomethyl-8-HQ derivatives were synthesized and their fluoroionophoric properties towardrepresentative alkali, alkaline earth, group IIIA and transition metal ions wereinvestigated. Among the selected ions, Zn(II) enhanced the fluorescence of N-di-(methoxycarbonylethyl)aminoethyl-3-[4-(8-hydroxyquinolin-5-ylmethyl)piperazin-1-yl]-propanoic amide] (7) by 31-fold, while Al(III) caused enhancement to some extent. Theabsence of any significant fluorescence enhancement by the other ions examined renders 7a highly useful Zn(II)-selective fluorescent sensor. Full article
Open AccessArticle New Monoterpenoid Coumarins from Clausena anisum-olens
Molecules 2008, 13(4), 931-937; doi:10.3390/molecules13040931
Received: 19 January 2008 / Revised: 17 April 2008 / Accepted: 17 April 2008 / Published: 19 April 2008
Cited by 14 | PDF Full-text (100 KB) | HTML Full-text | XML Full-text
Abstract Two new monoterpenoid coumarins: anisucumarin A (1) and B (2), a pair ofepimers, were isolated from Clausena anisum-olens. Their structures were establishedbased on extensive spectroscopic analyses. Full article
Open AccessCommunication Acid-catalyzed Epimerization of Kobophenol A to Carasinol B
Molecules 2008, 13(4), 938-942; doi:10.3390/molecules13040938
Received: 13 March 2008 / Revised: 4 April 2008 / Accepted: 4 April 2008 / Published: 19 April 2008
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Abstract The conversion from kobophenol A into carasinol B, two main chemicalconstituents of Caragana sinica, was confirmed by in vitro acid-catalyzed epimerization.The result provides important information about the biotransformation of kobophenol A inplants and its metabolism in rats. Full article
(This article belongs to the Special Issue Heterocycles)
Open AccessCommunication Efficient and Eco-Friendly Preparation of 4-Methyl-5-formyl-thiazole
Molecules 2008, 13(4), 943-947; doi:10.3390/molecules13040943
Received: 6 April 2008 / Revised: 17 April 2008 / Accepted: 17 April 2008 / Published: 21 April 2008
Cited by 7 | PDF Full-text (123 KB) | HTML Full-text | XML Full-text
Abstract 4-Methyl-5-formylthiazole, an intermediate for synthesizing cefditoren pivoxil,was prepared in good yield by Pd/BaSO4 catalyzed hydrogenation of 4-methylthiazole-5-carboxylic acid chloride. Detailed reaction conditions have been studied. Full article
Open AccessArticle CuO and Ag2O/CuO Catalyzed Oxidation of Aldehydes to the Corresponding Carboxylic Acids by Molecular Oxygen
Molecules 2008, 13(4), 948-957; doi:10.3390/molecules13040948
Received: 6 April 2008 / Revised: 17 April 2008 / Accepted: 17 April 2008 / Published: 21 April 2008
Cited by 17 | PDF Full-text (686 KB) | HTML Full-text | XML Full-text
Abstract
Furfural was oxidized to furoic acid by molecular oxygen under catalysis by 150nm-sized Ag2O/CuO (92%) or simply CuO (86.6%). When 30 nm-size catalyst was used,the main product was a furfural Diels-Alder adduct. Detailed reaction conditions andregeneration of catalysts were investigated. [...] Read more.
Furfural was oxidized to furoic acid by molecular oxygen under catalysis by 150nm-sized Ag2O/CuO (92%) or simply CuO (86.6%). When 30 nm-size catalyst was used,the main product was a furfural Diels-Alder adduct. Detailed reaction conditions andregeneration of catalysts were investigated. Under optimal conditions, a series of aromaticand aliphatic aldehydes were oxidized to the corresponding acids in good yields. Full article
Open AccessArticle Synthesis and Biological Activity of Peptide Derivatives of Iodoquinazolinones/Nitroimidazoles
Molecules 2008, 13(4), 958-976; doi:10.3390/molecules13040958
Received: 3 April 2008 / Revised: 18 April 2008 / Accepted: 19 April 2008 / Published: 24 April 2008
Cited by 21 | PDF Full-text (268 KB) | HTML Full-text | XML Full-text
Abstract
Two substituted quinazolinyl/imidazolyl-salicylic acids 5, 6 were synthesized bythe reaction of 6-iodo-2-methylbenzoxazin-4-one/5-nitroimidazole with 5-aminosalicylicacid (5-ASA). Coupling of compounds 5 and 6 with different amino acid esterhydrochlorides, dipeptide and tripeptide methyl esters yielded novelquinazolino/imidazolopeptide derivatives 5a-f and 6a-g. The chemical structures of allnewly [...] Read more.
Two substituted quinazolinyl/imidazolyl-salicylic acids 5, 6 were synthesized bythe reaction of 6-iodo-2-methylbenzoxazin-4-one/5-nitroimidazole with 5-aminosalicylicacid (5-ASA). Coupling of compounds 5 and 6 with different amino acid esterhydrochlorides, dipeptide and tripeptide methyl esters yielded novelquinazolino/imidazolopeptide derivatives 5a-f and 6a-g. The chemical structures of allnewly synthesized compounds were confirmed by means of FT-IR, 1H- and 13C-NMR, MSand elemental analysis. Selected peptide ester derivatives were further hydrolyzed by usinglithium hydroxide (LiOH) to afford the corresponding acid derivatives 5ba-da and 6ea-ga.All peptide derivatives were assayed for antimicrobial and anthelmintic activities againsteight pathogenic microbes and three earthworm species. Among the tested compounds, 5e,5d, 6e and their hydrolyzed analogs 5da and 6ea exhibited higher antimicrobial activityagainst Pseudomonas aeruginosa, Klebsiella pneumoniae and Candida albicans, and 5a,6g and 6ga displayed better antifungal activity against the dermatophytes Trichophytonmentagrophytes and Microsporum audouinii. Moreover, 6f and its hydrolyzed derivative6fa showed good anthelmintic activity against Megascoplex konkanensis, Pontoscotexcorethruses and Eudrilus eugeniea at dose of 2 mg mL–1. Full article
Open AccessArticle Microwave-Enhanced Sulphated Zirconia and SZ/MCM-41 Catalyzed Regioselective Synthesis of β-Amino Alcohols Under Solvent-Free Conditions
Molecules 2008, 13(4), 977-985; doi:10.3390/molecules13040977
Received: 8 April 2008 / Revised: 24 April 2007 / Accepted: 24 April 2008 / Published: 26 April 2008
Cited by 11 | PDF Full-text (284 KB) | HTML Full-text | XML Full-text
Abstract
A solvent-free approach for the regioselective synthesis of β-amino alcohols inshorter reaction times and higher yields, compared to conventional heating is described. Itinvolves microwave (MW) exposure of undiluted reactants in the presence of sulphatedzirconia (SZ) or sulphated zirconia over MCM-41 (SZM) as [...] Read more.
A solvent-free approach for the regioselective synthesis of β-amino alcohols inshorter reaction times and higher yields, compared to conventional heating is described. Itinvolves microwave (MW) exposure of undiluted reactants in the presence of sulphatedzirconia (SZ) or sulphated zirconia over MCM-41 (SZM) as catalyst. Both acid materialscan be easily recovered and reused. Full article
Open AccessArticle Fluorinated Analogs of Malachite Green: Synthesis and Toxicity
Molecules 2008, 13(4), 986-994; doi:10.3390/molecules13040986
Received: 21 March 2008 / Revised: 22 April 2008 / Accepted: 22 April 2008 / Published: 27 April 2008
Cited by 7 | PDF Full-text (285 KB) | HTML Full-text | XML Full-text
Abstract
A series of fluorinated analogs of malachite green (MG) have been synthesizedand their toxicity to Saccharomyces cerevisiae and a human ovarian epithelial cell lineexamined. The toxicity profiles were found to be different for these two species. Twoanalogs, one with 2,4-difluoro substitution and [...] Read more.
A series of fluorinated analogs of malachite green (MG) have been synthesizedand their toxicity to Saccharomyces cerevisiae and a human ovarian epithelial cell lineexamined. The toxicity profiles were found to be different for these two species. Twoanalogs, one with 2,4-difluoro substitution and the other with 2-fluoro substitution seem tobe the most promising analogs because they showed the lowest toxicity to the human cells. Full article
Open AccessArticle Novel Spiroannulated 3-Benzofuranones. Synthesis and Inhibition of the Human Peptidyl Prolyl cis/trans Isomerase Pin1
Molecules 2008, 13(4), 995-1003; doi:10.3390/molecules13040995
Received: 3 April 2008 / Revised: 22 April 2007 / Accepted: 23 April 2008 / Published: 29 April 2008
Cited by 15 | PDF Full-text (59 KB) | HTML Full-text | XML Full-text
Abstract
The novel 3H-spiro[1-benzofuran-2-cyclopentan]-3-one skeleton has been madeaccessible by different routes. One- and two-step protocols lead to tricyclic and tetracyclicbenzofuranones 2 and 3, respectively. A four-step synthesis to spirocompound 4 isdescribed. The novel spirocyclic benzofuranones display modest to no inhibition of thehuman peptidyl [...] Read more.
The novel 3H-spiro[1-benzofuran-2-cyclopentan]-3-one skeleton has been madeaccessible by different routes. One- and two-step protocols lead to tricyclic and tetracyclicbenzofuranones 2 and 3, respectively. A four-step synthesis to spirocompound 4 isdescribed. The novel spirocyclic benzofuranones display modest to no inhibition of thehuman peptidyl prolyl cis/trans isomerase Pin1. Full article
(This article belongs to the Special Issue Spiro Compounds)
Open AccessArticle Spectral Data of Two New Asymmetric Sesquiterpene Alcohols: (14R)-β-Oplopenol and (14S)-β-Oplopenol
Molecules 2008, 13(4), 1004-1010; doi:10.3390/molecules13041004
Received: 31 March 2008 / Revised: 28 April 2008 / Accepted: 28 April 2008 / Published: 29 April 2008
Cited by 1 | PDF Full-text (104 KB) | HTML Full-text | XML Full-text
Abstract The epimeric sesquiterpene alcohols (14R)-β-oplopenol and (14S)-β-oplopenolwere obtained by LiAlH4 reduction of β-oplopenone. The complete 1H- and 13C-NMRassignments of these two new sesquiterpene alcohols have been made using 1D and 2DNMR techniques, including COSY, NOESY, HSQC, HMBC experiments. Full article
Open AccessArticle Synthesis and Biological Activity of Some New Pyrazoline and Pyrrolo[3,4-c]pyrazole-4,6-dione Derivatives: Reaction of Nitrilimines with Some Dipolarophiles
Molecules 2008, 13(4), 1011-1024; doi:10.3390/molecules13041011
Received: 8 April 2008 / Revised: 22 April 2008 / Accepted: 22 April 2008 / Published: 29 April 2008
Cited by 20 | PDF Full-text (160 KB) | HTML Full-text | XML Full-text
Abstract Several 1,3-diaryl-5-(cyano-, aminocarbonyl- and ethoxycarbonyl-)-2-pyrazoline, pyrrolo[3,4-c]pyrazole-4,6-dione and 1,3,4,5-tetraaryl-2-pyrazoline derivativeswere prepared by the reaction of nitrilimine with different dipolarophilic reagents. The newcompounds were characterized using IR, 1H-NMR, 13C-NMR and mass spectra. Biologicalscreening of some compounds is reported. Full article

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Open AccessCorrection Correction to Oz, H.S.; Ebersole, Jeffrey L. Application of Prodrugs to Inflammatory Diseases of the Gut. Molecules 2008, 13, 452-474
Molecules 2008, 13(4), 771; doi:10.3390/molecules13040771
Received: 31 March 2008 / Accepted: 1 April 2008 / Published: 1 April 2008
Cited by 2 | PDF Full-text (17 KB) | HTML Full-text | XML Full-text

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