Molecules

252 KiB

Open AccessCommunication

A New Poly-substituted Benzaldehyde from the Leaves of Lysimachia fordiana Oliv.

by Xin-an Huang, Ren-zhou Yang and Wen-di Deng

Molecules 2007, 12(1), 43-48; https://doi.org/10.3390/12010043 - 22 Jan 2008

Cited by 3 | Viewed by 9841

A new poly-substituted benzaldehyde, 1, and a known compound quercetin (2) were isolated from the leaves of Lysimachia fordiana Oliv. The structure of compound 1, named fordianol, was determined as 2-heptyl-3,6-dihydroxy-4- methoxybenzaldehyde on the basis of spectroscopic methods. Fordianol did not inhibit the [...] Read more.

A new poly-substituted benzaldehyde, 1, and a known compound quercetin (2) were isolated from the leaves of Lysimachia fordiana Oliv. The structure of compound 1, named fordianol, was determined as 2-heptyl-3,6-dihydroxy-4- methoxybenzaldehyde on the basis of spectroscopic methods. Fordianol did not inhibit the growth of SWO-38 (human brain neuroglioma), MCF-7 (human breast cancer) or HeLa (human cervical carcinoma) cell lines. Full article

► Show Figures

Figure 1

82 KiB

Open AccessArticle

Salicylanilide Acetates: Synthesis and Antibacterial Evaluation

by Jarmila Vinsova, Ales Imramovsky, Vladimir Buchta, Martina Ceckova, Martin Dolezal, Frantisek Staud, Josef Jampilek and Jarmila Kaustova

Molecules 2007, 12(1), 1-12; https://doi.org/10.3390/12010001 - 01 Jan 2008

Cited by 48 | Viewed by 17957

Abstract

A new series of salicylanilide acetates was synthesized and evaluated for their in vitro antifungal and antituberculotic activity. Some of the evaluated compounds possessed comparable or better antifungal activity than a fluconazole standard. All these compounds exhibited very good potential and their in [...] Read more.

A new series of salicylanilide acetates was synthesized and evaluated for their in vitro antifungal and antituberculotic activity. Some of the evaluated compounds possessed comparable or better antifungal activity than a fluconazole standard. All these compounds exhibited very good potential and their in vitro activity against drug resistant and sensitive clinical isolates of Mycobacteria were found to be equivalent or better than a standard of isoniazide, a well-known first-line drug for tuberculosis treatment. Full article

► Show Figures

Figure 1

158 KiB

Open AccessArticle

Synthesis of Functionalised Nucleosides for Incorporation into Nucleic Acid-Based Serine Protease Mimics

by Mieke A. Catry and Annemieke Madder

Molecules 2007, 12(1), 114-129; https://doi.org/10.3390/12010114 - 31 Jan 2007

Cited by 14 | Viewed by 10689

Abstract

The synthesis of nucleosides modified with an extra imidazole, carboxyl and hydroxyl group is described. These nucleosides can be incorporated into an oligonucleotide duplex, thus generating a novel type of serine protease mimic. Full article

► Show Figures

Figure 1

73 KiB

Open AccessArticle

Synthesis and Antimicrobial Activity of Some New 1,3,4-Thiadiazole and 1,2,4-Triazole Compounds Having a D,L-Methionine Moiety

by Otilia Pintilie, Lenuta Profire, Valeriu Sunel, Marcel Popa and Aurel Pui

Molecules 2007, 12(1), 103-113; https://doi.org/10.3390/12010103 - 29 Jan 2007

Cited by 83 | Viewed by 15851

Abstract

New 1,3,4-thiadiazole, 5a-e, and 1,2,4-triazolecompounds 6a-c, containing a D,L-methionine moiety were synthesized by intramolecular cyclization of 1,4-disubstituted thiosemicarbazides 4a-e in acid and alkaline media, respectively. The potential antimicrobial effects of the synthesized compounds were investigated using the Staphylococcus aureus ATCC 25923, Bacillus [...] Read more.

New 1,3,4-thiadiazole, 5a-e, and 1,2,4-triazolecompounds 6a-c, containing a D,L-methionine moiety were synthesized by intramolecular cyclization of 1,4-disubstituted thiosemicarbazides 4a-e in acid and alkaline media, respectively. The potential antimicrobial effects of the synthesized compounds were investigated using the Staphylococcus aureus ATCC 25923, Bacillus antracis ATCC 8705, Bacillus cereus ATCC 10987, Sarcina lutea ATCC 9341 and Escherichia coli ATCC 25922 strains. The newly synthesized compounds exhibited promising activities against Bacillus antracis and Bacillus cereus. Full article

► Show Figures

Figure 1

47 KiB

Open AccessArticle

Antioxidant Activity and Total Phenols in Different Extracts of Four Staphylea L. Species

by Lubica Lacikova, Jan Muselik, Irena Masterova and Daniel Grancai

Molecules 2007, 12(1), 98-102; https://doi.org/10.3390/12010098 - 29 Jan 2007

Cited by 14 | Viewed by 13841

Abstract

Staphylea L. is a deciduous ornamental shrub that possesses significant cytotoxic and antibacterial activity, although the chemical composition of its extracts and the identity of the structures responsible for these biological activities are not yet known. In this study we have determined the [...] Read more.

Staphylea L. is a deciduous ornamental shrub that possesses significant cytotoxic and antibacterial activity, although the chemical composition of its extracts and the identity of the structures responsible for these biological activities are not yet known. In this study we have determined the total phenolic content in chloroform and ethyl acetate extracts of four Staphylea species: Staphylea colchica Stev., S. elegans Zab., S. holocarpa Hemsl. and S. pinnata L.. The antioxidant potential (DPPH radical and peroxynitrite scavenging activity) of these extracts was also determined and a correlation between the phenolic content and antioxidant activities of the ethyl acetate extracts has been found. Ethyl acetate extracts were more active and one of them, obtained from S. colchica Stev., possessed the highest activity. Full article

(This article belongs to the Special Issue Phenolics and Polyphenolics)

138 KiB

Open AccessArticle

Inhibitory Effects of 5,6,7-Trihydroxyflavones on Tyrosinase

by Hong Gao, Jun Nishida, Shizuka Saito and Jun Kawabata

Molecules 2007, 12(1), 86-97; https://doi.org/10.3390/12010086 - 29 Jan 2007

Cited by 43 | Viewed by 12326

Abstract

Baicalein (1), 6-hydroxyapigenin (6), 6-hydroxygalangin (13) and 6-hydroxy-kaempferol (14), which are naturally occurring flavonoids from a set of 14 hydroxy-flavones tested, exhibited high inhibitory effects on tyrosinase with respect to L-DOPA,while each of the 5,6,7-trihydroxyflavones 1, 6, 13 or 14 acted as a [...] Read more.

Baicalein (1), 6-hydroxyapigenin (6), 6-hydroxygalangin (13) and 6-hydroxy-kaempferol (14), which are naturally occurring flavonoids from a set of 14 hydroxy-flavones tested, exhibited high inhibitory effects on tyrosinase with respect to L-DOPA,while each of the 5,6,7-trihydroxyflavones 1, 6, 13 or 14 acted as a cofactor tomonophenolase. Moreover, 6-hydroxykaempferol (14) showed the highest activity andwas a competitive inhibitor of tyrosinase compared to L-DOPA. 5,6,7-Trihydroxyflavones 1, 6, 13 or 14 showed also high antioxidant activities. Hence, weconclude that the 5,6,7-trihydroxy-flavones are useful as good depigmentation agentswith inhibitory effects in addition to their antioxidant properties. Full article

(This article belongs to the Special Issue Phenolics and Polyphenolics)

► Show Figures

Figure 1

138 KiB

Open AccessArticle

Simple and Regioselective Bromination of 5,6-Disubstituted-indan-1-ones with Br₂ Under Acidic and Basic Conditions

by Taeyoung Choi and Eunsook Ma

Molecules 2007, 12(1), 74-85; https://doi.org/10.3390/12010074 - 29 Jan 2007

Cited by 11 | Viewed by 10175

Abstract

Bromination of 5,6-dimethoxyindan-1-one with Br₂ in acetic acid at room temperature produced exclusively the corresponding 2,4-dibromo compound in 95% yield. Reaction of 5,6-dimethoxyindan-1-one with Br₂ in the presence of KOH, K₂CO₃ or Cs₂CO₃at ~0°C [...] Read more.

Bromination of 5,6-dimethoxyindan-1-one with Br₂ in acetic acid at room temperature produced exclusively the corresponding 2,4-dibromo compound in 95% yield. Reaction of 5,6-dimethoxyindan-1-one with Br₂ in the presence of KOH, K₂CO₃ or Cs₂CO₃at ~0°Cgave the monobrominated product 4-bromo-5,6-dimethoxyindan-3-one in 79%, 81% and 67% yield, respectively. 5,6-Dihydroxyindan-1-one was dibrominated on the aromatic ring affording 4,7-dibromo-5,6-dihydroxyindan-1-one both in acetic acid at room temperature and in the presence of KOH at ~0°C. 5,6-Difluoroindan-1-one and 1-indanone were α-monobrominated in acetic acid and α,α-dibrominated under KOH conditions at room temperature. Full article

146 KiB

Open AccessArticle

A Convenient Approach to Heterocyclic Building Blocks: Synthesis of Novel Ring Systems Containing a [5,6]Pyrano[2,3-c]pyrazol-4(1H)-one Moiety

by Gernot Eller and Wolfgang Holzer

Molecules 2007, 12(1), 60-73; https://doi.org/10.3390/12010060 - 26 Jan 2007

Cited by 25 | Viewed by 10913

Abstract

Starting from commercially available educts, a straightforward synthetic route to new heterocyclic building blocks is exemplified with the one- or two-step synthesis of tri-, tetra-, or pentacyclic ring systems. Representatives of the following novel ring systems are prepared from 3-methyl-1-phenyl-2-pyrazolin-5-one and the corresponding [...] Read more.

Starting from commercially available educts, a straightforward synthetic route to new heterocyclic building blocks is exemplified with the one- or two-step synthesis of tri-, tetra-, or pentacyclic ring systems. Representatives of the following novel ring systems are prepared from 3-methyl-1-phenyl-2-pyrazolin-5-one and the corresponding o-halo-arenecarbonyl chloride using calcium hydroxide in refluxing 1,4-dioxane: pyrimidino[4',5':5,6]pyrano[2,3-c]pyrazol-4(1H)-one, thieno[3',2':5,6]pyrano[2,3c]pyrazol- 4-(1H)-one, thieno[3',4':5,6]pyrano[2,3-c]pyrazol-4(1H)-one, thieno[3'',2'':4',5']thieno[2',3':5,6]-pyrano[2,3-c]pyrazol-4(1H)-one, [1,3]dioxolo[5',6'][1]benzothieno[2',3':5,6]pyrano-[2,3-c]- pyrazol-4(1H)-one, pyridazino[4',3':5,6]pyrano[2,3-c]pyrazol-4(1H)-one and pyrazolo-[4'',3'':5',6']pyrido[3',4':5,6]pyrano[2,3-c]pyrazol-4(1H)-one. While the latter two ring systems are directly obtained due to a spontaneous intramolecular substitution reaction, in the other reactions uncyclised 4-aroylpyrazol-5-ols are produced, which are cyclised into the target heterocycles in a subsequent synthetic step (i.e. treatment with NaH in DMF). Detailed NMR spectroscopic investigations (¹H-, ¹³C-, ¹⁵N-) with the obtained compounds were undertaken to unambiguously prove the new structures. Full article

► Show Figures

Figure 1

110 KiB

Open AccessArticle

Microwave-Assisted Synthesis of Substituted Hexahydro-pyrrolo[3,2-c]quinolines

by Michal Neuschl, Darek Bogdal and Milan Potacek

Molecules 2007, 12(1), 49-59; https://doi.org/10.3390/12010049 - 24 Jan 2007

Cited by 21 | Viewed by 9014

Abstract

New compounds with the ethyl hexahydro-1H-pyrrolo[3,2-c]quinoline-2-carboxylate skeleton were prepared by microwave-assisted intramolecular 1,3-dipolar cycloaddition reactions. The reactions were carried out under solvent-free conditions and compared with the same reaction in the presence of a solvent and a catalyst. Steric [...] Read more.

New compounds with the ethyl hexahydro-1H-pyrrolo[3,2-c]quinoline-2-carboxylate skeleton were prepared by microwave-assisted intramolecular 1,3-dipolar cycloaddition reactions. The reactions were carried out under solvent-free conditions and compared with the same reaction in the presence of a solvent and a catalyst. Steric effects on the selectivity of the reaction were noted and evaluated. Full article

► Show Figures

Figure 1

120 KiB

Open AccessArticle

An Efficient Synthesis and Reactions of Novel Indol-ylpyridazinone Derivatives with Expected Biological Activity

by Samar A. Abubshait

Molecules 2007, 12(1), 25-42; https://doi.org/10.3390/12010025 - 10 Jan 2007

Cited by 29 | Viewed by 10330

Abstract

Reaction of 4-anthracen-9-yl-4-oxo-but-2-enoic acid (1) with indole gave the corresponding butanoic acid 2. Cyclocondensation of 2 with hydrazine hydrate, phenyl hydrazine, semicarbazide and thiosemicarbazide gave the pyridazinone derivatives 3a-d. Reaction of 3a with POCl₃ for 30 min gave the chloropyridazine derivative 4a, [...] Read more.

Reaction of 4-anthracen-9-yl-4-oxo-but-2-enoic acid (1) with indole gave the corresponding butanoic acid 2. Cyclocondensation of 2 with hydrazine hydrate, phenyl hydrazine, semicarbazide and thiosemicarbazide gave the pyridazinone derivatives 3a-d. Reaction of 3a with POCl₃ for 30 min gave the chloropyridazine derivative 4a, which was used to prepare the corresponding carbohydrate hydrazone derivatives 5a-d. Reaction of chloropyridazine 4a with some aliphatic or aromatic amines and anthranilic acid gave 6a-f and 7, respectively. When the reaction of the pyridazinone derivative 3a with POCl₃ was carried out for 3 hr an unexpected product 4b was obtained. The structure of 4b was confirmed by its reaction with hydrazine hydrate to give hydrazopyridazine derivative 9, which reacted in turn with acetyl acetone to afford 10. Reaction of 4b with methylamine gave 11, which reacted with methyl iodide to give the trimethylammonium iodide derivative 12. The pyridazinone 3a also reacted with benzene- or 4-toluenesulphonyl chloride to give 13a-b and with aliphatic or aromatic aldehydes to give 14a-g. All proposed structures were supported by IR, ¹H-NMR, ¹³C-NMR, and MS spectroscopic data. Some of the new products showed antibacterial activity. Full article

► Show Figures

Figure 1

550 KiB

Open AccessArticle

Synthesis, Characterization, and Saccharide Binding Studies of Bile Acid − Porphyrin Conjugates

by Juha Koivukorpi, Elina Sievänen, Erkki Kolehmainen and Vladimír Král

Molecules 2007, 12(1), 13-24; https://doi.org/10.3390/12010013 - 05 Jan 2007

Cited by 18 | Viewed by 10302

Abstract

Synthesis and characterization of bile acid-porphyrin conjugates (BAPs) are reported. Binding of saccharides with BAPs in aqueous methanol was studied by monitoring changes in the visible absorption spectral of the porphyrin-moieties. Although these studies clearly showed absorbance changes, suggesting quite high if non-selective [...] Read more.

Synthesis and characterization of bile acid-porphyrin conjugates (BAPs) are reported. Binding of saccharides with BAPs in aqueous methanol was studied by monitoring changes in the visible absorption spectral of the porphyrin-moieties. Although these studies clearly showed absorbance changes, suggesting quite high if non-selective binding, the mass spectral studies do not unambiguously support these results. Full article

(This article belongs to the Special Issue Bile Acids)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Molecules, Volume 12, Issue 1 (January 2007) – 11 articles , Pages 1-129

Further Information

Guidelines

MDPI Initiatives

Follow MDPI