Next Issue
Previous Issue

E-Mail Alert

Add your e-mail address to receive forthcoming issues of this journal:

Journal Browser

Journal Browser

Table of Contents

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

  • Issues are regarded as officially published after their release is announced to the table of contents alert mailing list.
  • You may sign up for e-mail alerts to receive table of contents of newly released issues.
  • PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Readerexternal link to open them.
View options order results:
result details:
Displaying articles 1-32
Export citation of selected articles as:
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; https://doi.org/10.3390/molecules13041011
Received: 8 April 2008 / Revised: 22 April 2008 / Accepted: 22 April 2008 / Published: 29 April 2008
Cited by 29 | 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
Figures

Figure 1

Open AccessArticle Spectral Data of Two New Asymmetric Sesquiterpene Alcohols: (14R)-β-Oplopenol and (14S)-β-Oplopenol
Molecules 2008, 13(4), 1004-1010; https://doi.org/10.3390/molecules13041004
Received: 31 March 2008 / Revised: 28 April 2008 / Accepted: 28 April 2008 / Published: 29 April 2008
Cited by 2 | 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
Figures

Figure 1

Open AccessArticle Novel Spiroannulated 3-Benzofuranones. Synthesis and Inhibition of the Human Peptidyl Prolyl cis/trans Isomerase Pin1
Molecules 2008, 13(4), 995-1003; https://doi.org/10.3390/molecules13040995
Received: 3 April 2008 / Revised: 22 April 2007 / Accepted: 23 April 2008 / Published: 29 April 2008
Cited by 17 | 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 prolyl
[...] 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)
Figures

Figure 1

Open AccessArticle Fluorinated Analogs of Malachite Green: Synthesis and Toxicity
Molecules 2008, 13(4), 986-994; https://doi.org/10.3390/molecules13040986
Received: 21 March 2008 / Revised: 22 April 2008 / Accepted: 22 April 2008 / Published: 27 April 2008
Cited by 15 | 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 the
[...] 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
Figures

Figure 1

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; https://doi.org/10.3390/molecules13040977
Received: 8 April 2008 / Revised: 24 April 2007 / Accepted: 24 April 2008 / Published: 26 April 2008
Cited by 12 | 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 catalyst.
[...] 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
Figures

Figure 1

Open AccessArticle Synthesis and Biological Activity of Peptide Derivatives of Iodoquinazolinones/Nitroimidazoles
Molecules 2008, 13(4), 958-976; https://doi.org/10.3390/molecules13040958
Received: 3 April 2008 / Revised: 18 April 2008 / Accepted: 19 April 2008 / Published: 24 April 2008
Cited by 27 | 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 synthesized
[...] 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
Figures

Figure 1

Open AccessArticle CuO and Ag2O/CuO Catalyzed Oxidation of Aldehydes to the Corresponding Carboxylic Acids by Molecular Oxygen
Molecules 2008, 13(4), 948-957; https://doi.org/10.3390/molecules13040948
Received: 6 April 2008 / Revised: 17 April 2008 / Accepted: 17 April 2008 / Published: 21 April 2008
Cited by 28 | 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. Under
[...] 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
Figures

Figure 1

Open AccessCommunication Efficient and Eco-Friendly Preparation of 4-Methyl-5-formyl-thiazole
Molecules 2008, 13(4), 943-947; https://doi.org/10.3390/molecules13040943
Received: 6 April 2008 / Revised: 17 April 2008 / Accepted: 17 April 2008 / Published: 21 April 2008
Cited by 9 | 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
Figures

Figure 1

Open AccessCommunication Acid-catalyzed Epimerization of Kobophenol A to Carasinol B
Molecules 2008, 13(4), 938-942; https://doi.org/10.3390/molecules13040938
Received: 13 March 2008 / Revised: 4 April 2008 / Accepted: 4 April 2008 / Published: 19 April 2008
Cited by 5 | PDF Full-text (177 KB) | HTML Full-text | XML Full-text
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)
Figures

Figure 1

Open AccessArticle New Monoterpenoid Coumarins from Clausena anisum-olens
Molecules 2008, 13(4), 931-937; https://doi.org/10.3390/molecules13040931
Received: 19 January 2008 / Revised: 17 April 2008 / Accepted: 17 April 2008 / Published: 19 April 2008
Cited by 20 | 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
Figures

Figure 1

Open AccessArticle Selective Dendritic Fluorescent Sensors for Zn(II)
Molecules 2008, 13(4), 922-930; https://doi.org/10.3390/molecules13040922
Received: 6 April 2008 / Revised: 17 April 2008 / Accepted: 18 April 2008 / Published: 19 April 2008
Cited by 12 | 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) caused
[...] 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
Figures

Figure 1

Open AccessArticle Antimicrobial and Antioxidative Activities of Bioactive Constituents from Hydnophytum formicarum Jack.
Molecules 2008, 13(4), 904-921; https://doi.org/10.3390/molecules13040904
Received: 1 April 2008 / Revised: 17 April 2008 / Accepted: 17 April 2008 / Published: 18 April 2008
Cited by 82 | 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 27
[...] 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
Figures

Figure 1

Open AccessArticle Cytoprotective Efficacy of Amifostine Against Radiation- Induced Rectal Toxicity: Objective and Subjective Grading Scales for Radiomucositis
Molecules 2008, 13(4), 892-903; https://doi.org/10.3390/molecules13040892
Received: 1 February 2008 / Revised: 16 April 2008 / Accepted: 16 April 2007 / Published: 18 April 2008
Cited by 7 | 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 the
[...] 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)
Figures

Figure 1

Open AccessArticle A Structure-Activity Study of Antibacterial Diterpenoids
Molecules 2008, 13(4), 882-891; https://doi.org/10.3390/molecules13040822
Received: 28 March 2008 / Revised: 16 April 2008 / Accepted: 17 April 2008 / Published: 17 April 2008
Cited by 68 | 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 a
[...] 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
Figures

Figure 1

Open AccessArticle Development of an Enzyme-linked Immuno-Sorbent Assay (ELISA) Method for Carbofuran Residues
Molecules 2008, 13(4), 871-881; https://doi.org/10.3390/molecules13040871
Received: 27 March 2008 / Revised: 14 April 2008 / Accepted: 14 April 2008 / Published: 17 April 2008
Cited by 15 | 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) was
[...] 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
Figures

Figure 1

Back to Top