Molecules

164 KiB

Open AccessArticle

Design, Synthesis, and Antitumor Activities of Some Novel Substituted 1,2,3-Benzotriazines

by Jin-Ling Lv, Rui Wang, Dan Liu, Gang Guo, Yong-Kui Jing and Lin-Xiang Zhao

Molecules 2008, 13(6), 1427-1440; https://doi.org/10.3390/molecules13061427 - 24 Jun 2008

Cited by 15 | Viewed by 9781

A series of novel substituted 1,2,3-benzotriazines based on the structures of vatalanib succinate (PTK787) and vandetanib (ZD6474) were designed and synthesized. The antiproliferative effects of these compounds were tested on microvascular endothelial cells (MVECs) using the MTT assay. Introduction of a methoxy and [...] Read more.

A series of novel substituted 1,2,3-benzotriazines based on the structures of vatalanib succinate (PTK787) and vandetanib (ZD6474) were designed and synthesized. The antiproliferative effects of these compounds were tested on microvascular endothelial cells (MVECs) using the MTT assay. Introduction of a methoxy and a 3-chloropropoxy group into the 1,2,3-benzotriazines increased the antiproliferative effects. 4-(3-Chloro-4- fluoroanilino)-7-(3-chloropropoxy)-6-methoxy-1,2,3-benzotriazine (8m) was the most effective compound. It was 4-10 fold more potent than PTK787 in inhibiting the growth of T47D breast cancer cells, DU145 and PC-3 prostate cancer cells, LL/2 murine Lewis lung cancer cells and B16F0 melanoma cells. Full article

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487 KiB

Open AccessArticle

Pre-fractionated Microbial Samples – The Second Generation Natural Products Library at Wyeth

by Melissa M. Wagenaar

Molecules 2008, 13(6), 1406-1426; https://doi.org/10.3390/molecules13061406 - 20 Jun 2008

Cited by 54 | Viewed by 11183

Abstract

From the beginning of the antibiotic era in the 1940s to the present, Wyeth has sustained an active research program in the area of natural products discovery. This program has continually evolved through the years in order to best align with the “current” [...] Read more.

From the beginning of the antibiotic era in the 1940s to the present, Wyeth has sustained an active research program in the area of natural products discovery. This program has continually evolved through the years in order to best align with the “current” drug discovery paradigm in the pharmaceutical industry. The introduction of highthroughput screening and the miniaturization of assays have created a need to optimize natural product samples to better suit these new technologies. Furthermore, natural product programs are faced with an ever shortening time period from hit detection to lead characterization. To address these issues, Wyeth has created a pre-fractionated natural products library using reversed-phase HPLC to complement their existing library of crude extracts. The details of the pre-fractionated library and a cost-benefit analysis will be presented in this review. Full article

(This article belongs to the Special Issue Natural Product Pre-fractionation)

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151 KiB

Open AccessCommunication

Two New Flavonol Glycosides from Sarcopyramis bodinieri var. delicate

by Xiu Min Wang, Chun Peng Wan, Shou Ran Zhou and Yan Qiu

Molecules 2008, 13(6), 1399-1405; https://doi.org/10.3390/molecules13061399 - 19 Jun 2008

Cited by 16 | Viewed by 10572

Abstract

Detailed chemical investigation of the herb Sarcopyramis bodinieri var. delicate resulted in the isolation of two new flavonol glycosides, namely, isorhamnetin-3-O-(6′′-OE- feruloyl)-β-D-glucopyranoside (1) and isorhamnetin-3-O-(6′′-O-E-feruloyl)-β-Dgalactopyranoside (2). In addition, four known compounds, quercetin-3-O-(6′′-acetyl)-β-Dglucopyranoside (3), isorhamnetin-3-O-(6′′-acetyl)-β-D-glucopyranoside (4), quercetin-3- O-(6′′-O-E-p-coumaroyl)-β-D-glucopyranoside (5), and isorhamnetin-3-O-(6′′-O-E-pcoumaroyl)- β-D-glucopyranoside (6) were [...] Read more.

Detailed chemical investigation of the herb Sarcopyramis bodinieri var. delicate resulted in the isolation of two new flavonol glycosides, namely, isorhamnetin-3-O-(6′′-OE- feruloyl)-β-D-glucopyranoside (1) and isorhamnetin-3-O-(6′′-O-E-feruloyl)-β-Dgalactopyranoside (2). In addition, four known compounds, quercetin-3-O-(6′′-acetyl)-β-Dglucopyranoside (3), isorhamnetin-3-O-(6′′-acetyl)-β-D-glucopyranoside (4), quercetin-3- O-(6′′-O-E-p-coumaroyl)-β-D-glucopyranoside (5), and isorhamnetin-3-O-(6′′-O-E-pcoumaroyl)- β-D-glucopyranoside (6) were obtained. The structures of the new isolates were determined by extensive spectroscopic analysis. Full article

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412 KiB

Open AccessReview

Tomato Derived Polysaccharides for Biotechnological Applications: Chemical and Biological Approaches

by Giuseppina Tommonaro, Annarita Poli, Salvatore De Rosa and Barbara Nicolaus

Molecules 2008, 13(6), 1384-1398; https://doi.org/10.3390/molecules13061384 - 19 Jun 2008

Cited by 25 | Viewed by 13531

Abstract

Recent studies concerning the isolation and purification of exopolysaccharides from suspension-cultured tomato (Lycopersicon esculentum L. var. San Marzano) cells and the description of a simple, rapid and low environmental impact method with for obtaining polysaccharides from solid tomato-processing industry wastes are reported. [...] Read more.

Recent studies concerning the isolation and purification of exopolysaccharides from suspension-cultured tomato (Lycopersicon esculentum L. var. San Marzano) cells and the description of a simple, rapid and low environmental impact method with for obtaining polysaccharides from solid tomato-processing industry wastes are reported. Their chemical composition, rheological properties and partial primary structure were determined on the basis of spectroscopic analyses (UV, IR, GC-MS, ¹H-, ¹³C-NMR). Moreover, the anticytotoxic activities of exopolysaccharides obtained from cultured tomato cells were tested in a brine shrimp bioassay and the preparation of biodegradable film by chemical processing of polysaccharides from solid tomato industry waste was also reported. Full article

(This article belongs to the Special Issue Polysaccharides: Organic Chemistry, Bioactivity and Analysis, including Those from Medicinal Plants and Fungi)

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283 KiB

Open AccessArticle

Fractionated Marine Invertebrate Extract Libraries for Drug Discovery

by Tim S. Bugni, Mary Kay Harper, Malcolm W.B. McCulloch, Jason Reppart and Chris M. Ireland

Molecules 2008, 13(6), 1372-1383; https://doi.org/10.3390/molecules13061372 - 19 Jun 2008

Cited by 47 | Viewed by 10787

Abstract

The high-throughput screening and drug discovery paradigm has necessitated a change in preparation of natural product samples for screening programs. In an attempt to improve the quality of marine natural products samples for screening, several fractionation strategies were investigated. The final method used [...] Read more.

The high-throughput screening and drug discovery paradigm has necessitated a change in preparation of natural product samples for screening programs. In an attempt to improve the quality of marine natural products samples for screening, several fractionation strategies were investigated. The final method used HP20SS as a solid support to effectively desalt extracts and fractionate the organic components. Additionally, methods to integrate an automated LCMS fractionation approach to shorten discovery time lines have been implemented. Full article

(This article belongs to the Special Issue Natural Product Pre-fractionation)

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295 KiB

Open AccessArticle

Camptothecinoids from the seeds of Taiwanese Nothapodytes foetida

by Shou-Fang Wu, Pei-Wen Hsieh, Chin-Chung Wu, Chia-Lin Lee, Shu-Li Chen, Chi-Yu Lu, Tian-Shung Wu, Fang-Rong Chang and Yang-Chang Wu

Molecules 2008, 13(6), 1361-1371; https://doi.org/10.3390/molecules13061361 - 16 Jun 2008

Cited by 32 | Viewed by 12608

Abstract

Two new alkaloids, 9-methoxy-18,19-dehydrocamptothecin (1) and 5- hydroxymappicine-20-O-β-glucopyranoside (2a/2b as a racemic mixture), together with nine known compounds: camptothecin (3), 9-methoxy-camptothecin (4), 5-hydroxycamptothecin (5a/5b racemic mixture), 5-hydroxy-9-methoxycamptothecin (6a/6b racemic mixture), diosmetin (7), apigenin (8), apigenin-7-O-glucopyranoside (9), rosin (cinnamyl- O-β-D-glucopyranoside) (10) and amarantholidoside IV [...] Read more.

Two new alkaloids, 9-methoxy-18,19-dehydrocamptothecin (1) and 5- hydroxymappicine-20-O-β-glucopyranoside (2a/2b as a racemic mixture), together with nine known compounds: camptothecin (3), 9-methoxy-camptothecin (4), 5-hydroxycamptothecin (5a/5b racemic mixture), 5-hydroxy-9-methoxycamptothecin (6a/6b racemic mixture), diosmetin (7), apigenin (8), apigenin-7-O-glucopyranoside (9), rosin (cinnamyl- O-β-D-glucopyranoside) (10) and amarantholidoside IV (11) were isolated from the immature seeds of Nothapodytes foetida (Wight) Sleumer. The structures were elucidated by spectroscopic analyses. In the present research, compounds 1, 3, 4, 5a/5b and 6a/6b, also showed in vitro cytotoxicity against six cancer cell lines (HepG2, Hep3B, MDA-MB- 231, MCF-7, A549, and Ca9-22). Among them, compound 1 exhibited significant cytotoxicity against these cancer cell lines, with IC₅₀ of 0.24-6.57 μM. Furthermore, HPLC profiles were developed for qualitative and quantitative analysis of these active constituents in different parts of this plant, including mature and immature seeds, leaves, stems and roots. The results revealed that compounds 3 and 4 have the highest concentrations, which are found in the roots part of the plant. Full article

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119 KiB

Open AccessArticle

Syntheses of Diheterocyclic Compounds Based on 2-Thioacetohydrazide-5,7-dimethyl-1,2,4-triazolo[1,5-a]- pyrimidine

by Zu-Ming Liu, Qiong Chen, Chao-Nan Chen, Hai-Yang Tu and Guang-Fu Yang

Molecules 2008, 13(6), 1353-1360; https://doi.org/10.3390/molecules13061353 - 13 Jun 2008

Cited by 3 | Viewed by 8654

Abstract

The syntheses of some diheterocyclic compounds from 2-thioacetohydrazide- 5,7-dimethyl-1,2,4-triazolo[1,5-a]pyrimidine (1) are described. Compound 1 can be converted into triazoles, 1,3,4-oxadiazoles, and 1,3,4-thiadiazoles. The structures of the intermediates and the target compounds were confirmed by ¹H-NMR, MS and elemental analyses. Full article

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96 KiB

Open AccessArticle

Ring Contracting Sulfur Extrusion from Oxidized Phenothiazine Ring Systems

by Steven C. Farmer and Seth H. Berg

Molecules 2008, 13(6), 1345-1352; https://doi.org/10.3390/molecules13061345 - 12 Jun 2008

Cited by 11 | Viewed by 9371

Abstract

Lithium, used in conjunction with sodium metal, produces a high yield of carbazole when reacted with phenothiazine-5-oxide or phenothiazine-5,5-dioxide. A high yield of 9-ethylcarbazole is also produced when these reagents react with 10-ethylphenothiazine, 10-ethylphenothiazine-5-oxide, and 10-ethylphenothiazine-5,5-dioxide. Degassed Raney nickel produces carbazole in high [...] Read more.

Lithium, used in conjunction with sodium metal, produces a high yield of carbazole when reacted with phenothiazine-5-oxide or phenothiazine-5,5-dioxide. A high yield of 9-ethylcarbazole is also produced when these reagents react with 10-ethylphenothiazine, 10-ethylphenothiazine-5-oxide, and 10-ethylphenothiazine-5,5-dioxide. Degassed Raney nickel produces carbazole in high yield when reacted with phenothiazine and phenothiazine-5-oxide. A moderate yield of 9-ethylcarbazole is produced when n-butyllithium is reacted with 10-ethylphenothiazine-5-oxide. Full article

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240 KiB

Open AccessArticle

Characterization of Aroma Active Compounds in Fruit Juice and Peel Oil of Jinchen Sweet Orange Fruit (Citrus sinensis (L.) Osbeck) by GC-MS and GC-O

by Yu Qiao, Bi Jun Xie, Yan Zhang, Yun Zhang, Gang Fan, Xiao Lin Yao and Si Yi Pan

Molecules 2008, 13(6), 1333-1344; https://doi.org/10.3390/molecules13061333 - 12 Jun 2008

Cited by 176 | Viewed by 25822

Abstract

Gas chromatography-mass spectrometry (GC-MS) and gas chromatographyolfactometry (GC-O) were used to determine the aromatic composition and aroma active compounds of fruit juice and peel oil of Jinchen sweet orange fruit. Totals of 49 and 32 compounds were identified in fruit juice and peel [...] Read more.

Gas chromatography-mass spectrometry (GC-MS) and gas chromatographyolfactometry (GC-O) were used to determine the aromatic composition and aroma active compounds of fruit juice and peel oil of Jinchen sweet orange fruit. Totals of 49 and 32 compounds were identified in fruit juice and peel oil, respectively. GC-O was performed to study the aromatic profile of Jinchen fruit juice and peel oil. A total of 41 components appeared to contribute to the aroma of fruit juice and peel oil. Twelve components were the odorants perceived in both samples. The aromatic compositions of fruit juice were more complex than that of peel oil. Ethyl butanoate, β-myrcene, octanal, linalool, α-pinene, and decanal were found to be responsible for the aromatic notes in fruit juice and peel oil. Nineteen components have been perceived only in the juice and ten compounds were described as aromatic components of only the peel oil by the panelists. These differences lead to the different overall aroma between fruit juice and peel oil. Full article

147 KiB

Open AccessArticle

Do Cultivar, Geographical Location and Crop Season Influence Phenolic Profile of Walnut Leaves?

by Joana S. Amaral, Patrícia Valentão, Paula B. Andrade, Rui C. Martins and Rosa M. Seabra

Molecules 2008, 13(6), 1321-1332; https://doi.org/10.3390/molecules13061321 - 12 Jun 2008

Cited by 35 | Viewed by 12164

Abstract

Walnut leaves from nine different cultivars (Arco, Franquette, Hartley, Lara, Marbot, Mayette, Meylannaise, Parisienne and Rego) were studied for their phenolic compounds. Samples were harvested along three consecutive years, at two different geographical locations, in order to evaluate if significant differences in the [...] Read more.

Walnut leaves from nine different cultivars (Arco, Franquette, Hartley, Lara, Marbot, Mayette, Meylannaise, Parisienne and Rego) were studied for their phenolic compounds. Samples were harvested along three consecutive years, at two different geographical locations, in order to evaluate if significant differences in the phenolics composition can be related with genetic, climatic or geographical factors. Nine compounds (3-caffeoylquinic, 3-p-coumaroylquinic and 4-p-coumaroylquinic acids, quercetin 3- galactoside, quercetin 3-arabinoside, quercetin 3-xyloside, quercetin 3-rhamnoside, a quercetin 3-pentoside derivative and a kaempferol 3-pentoside derivative) were quantified using an HPLC-DAD methodology. The qualitative profiles were identical for all samples, but differences were observed in terms of individual compounds’ contents. Multivariate statistical analysis was carried out, showing that significant differences exist among production years, which can be related to climatic reasons. Full article

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63 KiB

Open AccessArticle

Efficient and Simple Synthesis of 6-Aryl-1,4-dimethyl-9H-carbazoles

by Anna Caruso, Anne Sophie Voisin-Chiret, Jean-Charles Lancelot, Maria Stefania Sinicropi, Antonio Garofalo and Sylvain Rault

Molecules 2008, 13(6), 1312-1320; https://doi.org/10.3390/molecules13061312 - 11 Jun 2008

Cited by 40 | Viewed by 10921

Abstract

A synthetic method for the preparation of 6-aryl-1,4-dimethyl-9H-carbazoles involving a palladium catalyzed coupling reaction of 1,4-dimethyl-9H-carbazole-6-boronic acids and (hetero)aryl halides is described. Full article

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139 KiB

Open AccessCommunication

Unusual Regioselectivity in the Opening of Epoxides by Carboxylic Acid Enediolates

by Luis R. Domingo, Salvador Gil, Margarita Parra and José Segura

Molecules 2008, 13(6), 1303-1311; https://doi.org/10.3390/molecules13061303 - 9 Jun 2008

Cited by 5 | Viewed by 11359

Abstract

Addition of carboxylic acid dianions appears to be a potential alternative to the use of aluminium enolates for nucleophilic ring opening of epoxides. These conditions require the use of a sub-stoichiometric amount of amine (10% mol) for dianion generation and the previous activation [...] Read more.

Addition of carboxylic acid dianions appears to be a potential alternative to the use of aluminium enolates for nucleophilic ring opening of epoxides. These conditions require the use of a sub-stoichiometric amount of amine (10% mol) for dianion generation and the previous activation of the epoxide with LiCl. Yields are good, with high regioselectivity, but the use of styrene oxide led, unexpectedly, to a mixture resulting from the attack on both the primary and secondary carbon atoms. Generally, a low diastereoselectivity is seen on attack at the primary center, however only one diastereoisomer was obtained from attack to the secondary carbon of the styrene oxide. Full article

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168 KiB

Open AccessReview

Stable Spirocyclic Meisenheimer Complexes

by Rabih O. Al-Kaysi, Iluminada Gallardo and Gonzalo Guirado

Molecules 2008, 13(6), 1282-1302; https://doi.org/10.3390/molecules13061282 - 9 Jun 2008

Cited by 36 | Viewed by 19403

Abstract

Meisenheimer complexes are important intermediates in Nucleophilic Aromatic Substitution Reactions (S_NAr). They are formed by the addition of electron rich species to polynitro aromatic compounds or aromatic compounds with strong electron withdrawing groups. It is possible to distinguish two types of [...] Read more.

Meisenheimer complexes are important intermediates in Nucleophilic Aromatic Substitution Reactions (S_NAr). They are formed by the addition of electron rich species to polynitro aromatic compounds or aromatic compounds with strong electron withdrawing groups. It is possible to distinguish two types of Meisenheimer or σ-complexes, the σ^Hcomplex or σ^X-complex (also named ipso), depending on the aromatic ring position attacked by the nucleophile (a non-substituted or substituted one, respectively). Special examples of σ^X- or ipso-complexes are formed through intermediate spiro adducts, via intramolecular SNAr. Some of these spirocyclic Meisenheimer complexes, a type of σ^Xcomplex, are exceptionally stable in solution and/or as solids. They can be isolated and characterized using X-ray, and various spectroscopic techniques such as NMR, UV-Vis, IR, and fluorescence. A few of these stable spirocyclic Meisenheimer complexes are zwitterionic and exhibit interesting photophysical and redox properties. We will review recent advances, synthesis and potential applications of these stable spirocyclic Meisenheimer complexes. Full article

(This article belongs to the Special Issue Spiro Compounds)

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133 KiB

Open AccessCommunication

A New Sesquiterpenoid Hydroquinone from the Marine Sponge Dysidea arenaria

by Yan Qiu and Xiu Min Wang

Molecules 2008, 13(6), 1275-1281; https://doi.org/10.3390/molecules13061275 - 6 Jun 2008

Cited by 31 | Viewed by 9179

Abstract

Detailed chemical investigation of the South China sponge Dysidea arenaria resulted in the isolation of a new sesquiterpenoid hydroquinone, 19-hydroxypolyfibrospongol B (1), along with five known compounds: polyfibrospongol B (2), isosemnonorthoquinone (3), ilimaquinone (4), smenospongine (5) and smenotronic acid (6). The structures were [...] Read more.

Detailed chemical investigation of the South China sponge Dysidea arenaria resulted in the isolation of a new sesquiterpenoid hydroquinone, 19-hydroxypolyfibrospongol B (1), along with five known compounds: polyfibrospongol B (2), isosemnonorthoquinone (3), ilimaquinone (4), smenospongine (5) and smenotronic acid (6). The structures were determined by extensive spectroscopic analysis. The in vitro anti- HIV activity on HIV-1 RT was evaluated. Compounds 3 -6 displayed moderate inhibitory activity, with IC₅₀values of 239.7, 16.4, 176.1, and 130.4 μM, respectively, while 1 and 2 were found to be inactive against the same biological target. Full article

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147 KiB

Open AccessArticle

Preparation of Chitosan from Brine Shrimp (Artemia urmiana) Cyst Shells and Effects of Different Chemical Processing Sequences on the Physicochemical and Functional Properties of the Product

by Hossein Tajik, Mehran Moradi, Seyed Mehdi Razavi Rohani, Amir Mehdi Erfani and Farnood Shokouhi Sabet Jalali

Molecules 2008, 13(6), 1263-1274; https://doi.org/10.3390/molecules13061263 - 6 Jun 2008

Cited by 83 | Viewed by 18967

Abstract

Chitosan (CS) was prepared from Artemia urmiana cyst shells using the same chemical process as described for the other crustacean species, with minor adjustments in the treatment conditions. The influence of modifications of the CS production process on the physiochemical and functional properties [...] Read more.

Chitosan (CS) was prepared from Artemia urmiana cyst shells using the same chemical process as described for the other crustacean species, with minor adjustments in the treatment conditions. The influence of modifications of the CS production process on the physiochemical and functional properties of the CS obtained was examined. The study results indicate that Artemia urmiana cyst shells are a rich source of chitin as 29.3-34.5% of the shell’s dry weight consisted of this material. Compared to crab CS (selected as an example of CS from a different crustacean source) Artemia CS exhibited a medium molecular weight (4.5-5.7 ×10⁵ Da), lower degree of deacetylation (67-74%) and lower viscosity (29-91 centiposes). The physicochemical characteristics (e.g., ash, nitrogen and molecular weight) and functional properties (e.g., water binding capacity and antibacterial activity) of the prepared Artemia CSs were enhanced, compared to control and commercial samples, by varying the processing step sequence. Full article

(This article belongs to the Special Issue Polysaccharides: Organic Chemistry, Bioactivity and Analysis, including Those from Medicinal Plants and Fungi)

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316 KiB

Open AccessArticle

Diterpenes from the Brown Alga Dictyota crenulata

by Joel Campos De-Paula, Ludmila Bomeny Bueno, Diana Negrão Cavalcanti, Yocie Yoneshigue-Valentin and Valéria Laneuville Teixeira

Molecules 2008, 13(6), 1253-1262; https://doi.org/10.3390/molecules13061253 - 4 Jun 2008

Cited by 22 | Viewed by 10145

Abstract

The crude extract of the Brazilian brown alga Dictyota crenulata was analyzed by NMR spectroscopy and HRGC-MS techniques. Seven diterpenes were identified: pachydictyol A, dictyodial, 4β-hydroxydictyodial A, 4β-acetoxydictyodial A, isopachydictyol A, dictyol C and dictyotadiol. Xeniane diterpenes have previously been found in D. [...] Read more.

The crude extract of the Brazilian brown alga Dictyota crenulata was analyzed by NMR spectroscopy and HRGC-MS techniques. Seven diterpenes were identified: pachydictyol A, dictyodial, 4β-hydroxydictyodial A, 4β-acetoxydictyodial A, isopachydictyol A, dictyol C and dictyotadiol. Xeniane diterpenes have previously been found in D. crenulata from the Pacific Ocean. The results characterize D. crenulata as a species that provides prenylated guaiane (group I) and xeniane diterpenes (group III), thus making it a new source of potential antiviral products. Full article

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178 KiB

Open AccessArticle

Density Functional Theory Study of the Trans-Trans-Cis (TTC)→Trans-Trans-Trans (TTT) Isomerization of a Photochromic Spiropyran Merocyanine

by Grazia Cottone, Rosina Noto and Gianfranco La Manna

Molecules 2008, 13(6), 1246-1252; https://doi.org/10.3390/molecules13061246 - 3 Jun 2008

Cited by 17 | Viewed by 12991

Abstract

Density Functional Theory (DFT) calculations have been performed on the TTC→TTT isomerization reaction of the open forms of the 1',3'-dihydro-8-bromo-6-nitro- 1',3',3'-trimethylspiro[2H-1-benzopyran-2,2'-(2H)indole (8-Br-6-nitro-BIPS) system. The calculations were carried out in vacuo and in methylene chloride solution at different temperatures. Results are compared with the [...] Read more.

Density Functional Theory (DFT) calculations have been performed on the TTC→TTT isomerization reaction of the open forms of the 1',3'-dihydro-8-bromo-6-nitro- 1',3',3'-trimethylspiro[2H-1-benzopyran-2,2'-(2H)indole (8-Br-6-nitro-BIPS) system. The calculations were carried out in vacuo and in methylene chloride solution at different temperatures. Results are compared with the available experimental values of free energy difference and activation energy in solution. Full article

(This article belongs to the Special Issue Spiro Compounds)

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176 KiB

Open AccessArticle

Anthocyanin Characterization of Pilot Plant Water Extracts of Delonix regia Flowers

by Felix Adje, Yves F. Lozano, Emmanuelle Meudec, Paul Lozano, Augustin Adima, Georges Agbo N’zi and Emile M. Gaydou

Molecules 2008, 13(6), 1238-1245; https://doi.org/10.3390/molecules13061238 - 1 Jun 2008

Cited by 24 | Viewed by 19334

Abstract

Following the development of new applications of pilot plant scale extraction and formulation processes for natural active bioproducts obtained from various underutilized tropical plants and herbs, we have manufactured water-extracts from Delonix regia flowers, grown in Ivory Coast. These extracts, which contain polyphenols, [...] Read more.

Following the development of new applications of pilot plant scale extraction and formulation processes for natural active bioproducts obtained from various underutilized tropical plants and herbs, we have manufactured water-extracts from Delonix regia flowers, grown in Ivory Coast. These extracts, which contain polyphenols, are traditionally home made and used as healthy bioproducts. They are reddish-coloured due to the presence of anthocyanins. The three major anthocyanins in these extracts have been characterized. The molecular structures were confirmed by LC-SM analysis. Amongst them, two are described for the first time in Delonix regia. Full article

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52 KiB

Open AccessArticle

Conversion of Oximes to Carbonyl Compounds by Triscetylpyridinium Tetrakis(oxodiperoxotungsto) Phosphate (PCWP)-mediated Oxidation with Hydrogen Peroxide

by Francesco P. Ballistreri, Ugo Chiacchio, Antonio Rescifina, Gaetano Tomaselli and Rosa M. Toscano

Molecules 2008, 13(6), 1230-1237; https://doi.org/10.3390/molecules13061230 - 1 Jun 2008

Cited by 18 | Viewed by 9316

Abstract

Aromatic and aliphatic oximes have been deoximated in chloroform-water to the corresponding aldehydes with dilute hydrogen peroxide and triscetylpyridinium tetrakis (oxodiperoxotungsto) phosphate as catalyst. The presence of dipolarophiles in the reaction mixtures allows a competitive reaction that converts oximes into isoxazole and isoxazoline [...] Read more.

Aromatic and aliphatic oximes have been deoximated in chloroform-water to the corresponding aldehydes with dilute hydrogen peroxide and triscetylpyridinium tetrakis (oxodiperoxotungsto) phosphate as catalyst. The presence of dipolarophiles in the reaction mixtures allows a competitive reaction that converts oximes into isoxazole and isoxazoline derivatives via the intermediate formation of nitrile oxide species. Full article

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130 KiB

Open AccessArticle

Identification of Minor Secondary Metabolites from the Latex of Croton lechleri (Muell-Arg) and Evaluation of Their Antioxidant Activity

by Simona De Marino, Fulvio Gala, Franco Zollo, Sara Vitalini, Gelsomina Fico, Francesco Visioli and Maria Iorizzi

Molecules 2008, 13(6), 1219-1229; https://doi.org/10.3390/molecules13061219 - 1 Jun 2008

Cited by 62 | Viewed by 19349

Abstract

Dragon’s blood (Sangre de drago), a viscous red sap derived from Croton lechleri Muell-Arg (Euphorbiaceae), is extensively used by indigenous cultures of the Amazonian basin for its wound healing properties. The aim of this study was to identify the minor secondary metabolites and [...] Read more.

Dragon’s blood (Sangre de drago), a viscous red sap derived from Croton lechleri Muell-Arg (Euphorbiaceae), is extensively used by indigenous cultures of the Amazonian basin for its wound healing properties. The aim of this study was to identify the minor secondary metabolites and test the antioxidant activity of this sustance. A bioguided fractionation of the n-hexane, chloroform, n-butanol, and aqueous extracts led to the isolation of 15 compounds: three megastigmanes, four flavan-3-ols, three phenylpropanoids, three lignans, a clerodane, and the alkaloid taspine. In addition to these known molecules, six compounds were isolated and identified for the first time in the latex: blumenol B, blumenol C, 4,5-dihydroblumenol A, erythro-guaiacyl-glyceryl-β-O-4’- dihydroconiferyl ether, 2-[4-(3-hydroxypropyl)-2-methoxyphenoxy]-propane-1,3-diol and floribundic acid glucoside. Combinations of spectroscopic methods (¹H-, ¹³C- NMR and 2D-NMR experiments), ESI-MS, and literature comparisons were used for compound identification. In vitro antioxidant activities were assessed by DPPH, total antioxidant capacity and lipid peroxidation assays. Flavan-3-ols derivatives (as major phenolic compounds in the latex) exhibited the highest antioxidant activity. Full article

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Molecules, Volume 13, Issue 6 (June 2008) – 20 articles , Pages 1219-1440

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