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A mild and efficient one-flask method has been developed for the synthesis of chromones, isoflavones, and homoisoflavones from 2-hydroxyacetophenones, deoxybenzoins, and dihydrochalcones, respectively, via one-carbon extension using the complex 2,4,6-trichloro-1,3,5-triazine/dimethylformamide. Deoxybenzoins and dihydrochalcones were prepared in situ by the reaction of readily available substituted phenols with phenylacetic acids and 3-phenylpropanoic acids, respectively. This method allows the synthesis of a wide range of compounds with multiple phenolic hydroxyls and other substituents. The methodology has been applied to the synthesis of three naturally occurring isoflavones such as formononetin (9c), daidzein (9d), and retusin (9h). Key words: chromone, isoflavone, homoisoflavone, B[F.sub.3] x [Et.sub.2]O, cyanuric chloride, dimethylformamide. On a mis au point une methode monotope douce et efficace de synthese de chromones, d'isoflavones et d'homoisoflavones a partir de 2-hydroxyacetophenones, de desoxybenzoines et de dihydrochalcones respectivement par allongement de la chame carbonee d'un atome en utilisant le complexe 2,4,6-trichloro-1,3,5-triazine/dimethylformamide. Les desoxybenzoines et les dihydrochalcones ont ete preparees in situ par reaction de phenols substitues faciles a obtenir avec des acides phenylacetiques et des acides 3-phenylpropanoiques respectivement. Cette methode permet de synthetiser une vaste gamme de composes portant plusieurs groupements hydroxyles phenoliques et d'autres substituants. La methode a ete appliquee a la synthese de trois isoflavones naturelles, a savoir la formononetine (9c), la daidzeine (9d) et la retusine (9h). [Traduit par la Redaction] Mots-cles: chromone, isoflavone, homoisoflavone, B[F.sub.3] x [Et.sub.2]O, chlorure cyanurique, dimethylformamide., Introduction The ubiquitous chromones (4H-chromen-4-ones) have attracted more attention in both industrial and academic fields for decades. (1) This interest arises from the fact that a variety of natural and [...]

Several attempts have been made for green synthesis of copper oxide nanoparticles (CuO-NPs) using different plant extracts. The present study revealed that, antibacterial and CuO-NPs were synthesized using ecofriendly and non-toxic Balanites aegyptiaca stem bark extract. The biosynthesized CuO-NPs were characterized by using UV–Vis analysis, Fourier Transform Infrared analysis (FTIR), X-ray diffraction analysis (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray analysis (EDX) and Transmission Electron Microscopy (TEM) analysis. In addition, the antibacterial activity of green synthesized CuO-NPs was tested using the agar well diffusion method against four bacterial pathogens “viz”: E. coli, V. cholerae, B. substilis and E. faecalis, which were responsible for causing severe infectious diseases in human being. CuO NPs exhibited enhanced antibacterial activity against the pathogen of B. subtilis i.e. 13 mm. Hence, CuO-NPs have the potential to be used as bactericidal component.

One-pot, four component, green, and efficient synthesis of 3-amino-1-(5-nitro-1H-indol-2-yl)-5,10-dioxo-5,10-dihydro-1H-pyrazolo[1,2-b]phthalazine derivatives by reaction of phthalic anhydride with hydrazine hydrate, 5-nitro-1H-indole-3-carboxaldehyde-indole-3-carboxaldehydes and malononitrile-ethyl cyanoacetate in the presence of [DBUH][OAc] at 60-65°C is developed. The method is characterized by short reaction time, high yields, and purity of products formed. [ABSTRACT FROM AUTHOR]

Urea/thiourea have been identified as an effective ammonia surrogate in the construction of quinazolin-4(3H)-one ring. This strategy afforded a simple and catalyst-free synthesis of 2-substituted 2,3-dihydroquinazolin-4(1H)-ones and quinazolin-4(3H)-ones via the reaction of isatoic anhydride and aryl aldehydes in the presence of urea or thiourea in ethanol. The reaction proceeded well to afford the quinazolin-4(3H)-one or its dihydro derivative, depending on the nature of carbonyl compounds employed. [ABSTRACT FROM PUBLISHER]

We report a facile, one-pot, three-component methodology for the synthesis of 8 H-quinazolino[4,3-b]quinazolin-8-ones from commercially available 2-aminobenzonitriles, triethyl orthoformate, and anthranilic acids/esters/amides in good yields. [ABSTRACT FROM AUTHOR]

A simple and alternative method has been developed for the synthesis of 4-benzylidene-2-phenyl-5(4H)-oxazolones via reactions of hippuric acid with various aldehydes in the presence of 2-chloro-4,6-dimethoxy-1,3,5-triazine/N-methylmorpholine at 75 °C. Supplemental materials are available for this article. Go to the publisher's online edition ofSynthetic Communications®to view the free supplemental file. [ABSTRACT FROM AUTHOR]

The synthesis of a recently identified and highly active sex pheromone of the longtailed mealybug, Pseudococcus longispinus is reported. A concise synthetic route, use of the under explored Meyer-Schuster rearrangement, Claisen rearrangement, and ringclosing metathesis are the highlights of this work. [ABSTRACT FROM AUTHOR]

Hantzsch 1,4-dihydropyridines and polyhydroquinoline derivatives were synthesized in good yields by PEG-mediated, catalyst–free synthesis under solvent-free conditions. The products were directly recrystallized from hot methanol. The reaction gave excellent yields with low- as well as high-molecular-weight polyethylene glycols. [ABSTRACT FROM PUBLISHER]

An efficient and convenient method was developed for the synthesis of novel 1,4-oxazepine- and 1,5-oxazocine-based sugar hybrids from readily available deoxysugar azides by means of tributylphosphine-mediated tandem reactions. The resulting glycoconjugates might be useful in increasing the diversity of sugar backbones, and could find applications as potential glycomimetics and in drug discovery. [ABSTRACT FROM AUTHOR]

Abstract A new series of phenolic glycoside esters, saccharumoside-B and its analogs (9b-9n, 10) have been synthesized by the Koenigs-Knorr reaction. Antiproliferative activities of the compounds (9b-9n, 10) were evaluated on various cancer cell lines including, MCF-7 breast, HL-60 leukemia, MIA PaCa-2 pancreatic, DU145 prostate, HeLa cervical and CaCo-2 colon, as well as normal human MCF10A mammary epithelial and human peripheral blood mononuclear cells (PBMC) by MTT assay. Compounds (9b-9n, 10) exhibited considerable antiproliferative effects against cancer cells with IC50 range of 4.43 ± 0.35 to 49.63 ± 3.59 µM, but they are less cytotoxic on normal cells (IC50 > 100 µM). Among all the compounds, 9f showed substantial antiproliferative activity against MCF-7 and HL-60 cells with IC50 of 6.13 ± 0.64 and 4.43 ± 0.35, respectively. Further mechanistic studies of 9f were carried out on MCF-7 and HL-60 cell lines. 9f caused arrest of cell cycle of MCF-7 and HL-60 cells at G0/G1 phase. Apoptotic population elevation, mitochondrial membrane potential loss, increase of cytosolic cytochrome c and Bax levels, decrease of Bcl-2 levels and enhanced caspases-9 and -3 activities were observed in 9f-treated MCF-7 and HL-60 cells. These results demonstrate anticancer and apoptosis-inducing potentials of 9f in MCF-7 and HL-60 cells via intrinsic pathway.

via simple reaction of hippuric acid (I) with various aldehydes (II) [ABSTRACT FROM AUTHOR]

The reaction is conducted under environmentally benign conditions. [ABSTRACT FROM AUTHOR]

An abstract of the article "PEG-mediated Facile Protocol for N-Boc Protection of Amines," by V. Siddaiah and colleagues is presented.

Abstract: A convenient one-step method for the synthesis of novel dihydrooxazine and oxazoline based sugar hybrids is reported starting from the readily accessible sugar azides and aldehydes. We have used Aubé’s protocol to achieve this transformation. The resulting glycoconjugates could be used to increase the diversity on the sugar backbone and may find applications as potential glycomimetics and in drug discovery. [Copyright &y& Elsevier]

In the present study, the supercritical carbon dioxide (CO2) extraction of oil from Simarouba gluaca seeds was carried out at varying conditions of pressure (300-500 bar), temperature (50-70 °C) and CO2 flow rate (10-30 g⋅min-1). The extraction condition for maximum oil yield was obtained at 500 bar pressure, 70 °C and at 30 g⋅min-1 flow rate of CO2. The extracted oil was analyzed thoroughly for physico-chemical properties and compared with those of conventional solvent extracted oil. An interesting observation is a significant reduction in the phosphorus content of the oil (8.4 mg⋅kg-1) extracted using supercritical CO2 compared to the phosphorous content of the solvent extracted oil (97 mg⋅kg-1). Moreover, the content of total tocopherols in supercritically extracted oil (135.6 mg⋅kg-1) was found to be higher than the solvent extracted oil (111 mg⋅kg-1). The rest of the physico-chemical properties of the two differently extracted oils matched well with each other. The results indicated the possible benefits of supercritical CO2 extraction over solvent extraction of Simarouba gluaca seed oil. [ABSTRACT FROM AUTHOR]

Highly stereoselective total syntheses of polyhydroxylated piperidines d -fagomine and 2- epi -fagomine have been developed starting from 3,4,6-tri- O -benzyl- d -glucal which is a derivative of d -Glucose. Key steps in the synthesis of these azasugars involved N -Boc-protected amine preparation from oxime followed by stereo specific iodination of alcohol and cascade cyclization triggered by N -Boc deprotection. [ABSTRACT FROM AUTHOR]