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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.

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.

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]

A sudden increase in life-threatening COVID-19 infections around the world inflicts global crisis and emotional trauma. In current study two druggable targets, namely SARS-COV-2 M pro and CCR-5 were selected due to their significant nature in the viral life cycle and cytokine molecular storm respectively. The systematic drug repurposing strategy has been utilized to recognize inhibitory mechanism through extensive in silico investigation of novel Maraviroc analogues as promising inhibitors against SARS-CoV-2 M pro and CCR-5. The dual inhibition specificity approach implemented in present study using molecular docking, molecular dynamics (MD), principal component analysis (PCA), free energy landscape (FEL) and MM/PBSA binding energy studies. The proposed Maraviroc analogues obtained from in silico investigation could be easily synthesized and constructive in developing significant drug against COVID-19 pandemic, with essentiality of their in vivo / in vitro evaluation to affirm the conclusions of this study. This will further fortify the concept of single drug targeting dual inhibition mechanism for treatment of COVID-19 infection and complications.

An improved and rapid synthesis of mefenamic acid based indole derivatives has been achieved via the ligand free Cu-catalyzed coupling-cyclization method under ultrasound irradiation. This simple, straightforward and inexpensive one-pot method involved the reaction of a terminal alkyne derived from mefenamic acid with 2-iodosulfanilides in the presence of CuI and K 2 CO 3 in PEG-400. The reaction proceeded via an initial CC bond formation (the coupling step) followed by CN bond formation (the intramolecular cyclization) to afford the mefenamic acid based indole derivatives in good to acceptable yields. Several of these compounds showed inhibition of PDE4 in vitro and the SAR (Structure Activity Relationship) within the series is discussed. The compound 3d has been identified as a promising and selective inhibitor of PDE4B (IC 50  = 1.34 ± 0.46 µM) that showed TNF-α inhibition in vitro (IC 50  = 5.81 ± 0.24 µM) and acceptable stability in the rat liver microsomes., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

A novel approach for the spiro-isoindolinone dihydroquinazolinones has been demonstrated from 2-aminobenzamide and 2-cyanomethyl benzoate in the presence of KHMDS as a base to get moderate yields. The reaction has been screened in various bases followed by solvents and a gram scale reaction has also been executed under the given conditions. Based on the controlled experiments a plausible reaction mechanism has been proposed. Further the substrate scope of this reaction has also been studied., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

In the present study, the dynamic viscoelastic behavior (DVB) and flow behavior of fresh tilapia ( Oreochromis mossambicus ) meat containing cryoprotectants were evaluated with and without water washing. The DVB profile of washed meat with 4% sucrose and sorbitol indicated the maximum structure buildup reaction up to 56.8 °C; thereafter, hydrophobic interactions leading to decreased gelation were suppressed. In both the samples, there was no clear indication of the sol-gel transition temperature. In flow-profile measurements, the presence of cryoprotectants gave rise to the minimum thixotropic area, indicating a low level of impairment in structure. The shear-stress sweep of water-washed tilapia proteins added with cryoprotectants did not reveal significant changes at 28 and 40 °C. In texture-profile analysis, the hardness values were lower in fresh meat than cooked meat. The findings of this study will be helpful in the formulation and design of various mince-based products and in determining the appropriate use of cryoprotectants and water washing in the processing of minced meat., Competing Interests: Compliance with ethical standardsThe authors declare no conflict of interest.

A unique oxidative dehydration-oxidation of polyhydroxy-oxime (7) to the corresponding ketonitrile (8) in one pot is reported for the first time in carbohydrate literature. Key ketonitrile intermediate (8) upon palladium hydroxide mediated cascade reaction afforded 1-deoxynojirimycin (DNJ) 1b in moderate diastereoselectivity. The cascade reaction involves the conversion of nitrile to amine, heteroannulation, reduction of the imine and subsequent debenzylation to furnish the azasugars. This oxidative dehydration-oxidation and reductive heteroannulation methodology is successfully utilized for the total synthesis of 1-deoxynojirimycin (1b), miglitol (2) and miglustat (3)., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Intricatinol and intricatin, the two homoisoflavonoids isolated from Hoffmanosseggia intricata, and two analogs have been synthesized from pyrogallol in three steps. The spectral data of synthetic intricatinol are in good agreement with those of natural metabolite, but the spectral data of intricatin are not corroborative with those of the natural product. The structure of intricatin has been thus revised to 8-methoxybonducellin, a compound isolated from Caesalpinia pulcherrima. The antioxidant activity of all the four homoisoflavonoids was determined by superoxide (NBT) and DPPH free radical scavenging methods. The synthetic analog 7,8-dihydroxy-3-[(3,4-dihydroxyphenyl)methylene]chroman-4-one displayed excellent activity in both methods.

Two new homoisoflavonoids, (E)-7-methoxy-3-(4'-methoxybenzylidene)chroman-4-one (1) and (E)-7-hydroxy-3-(3',4',5'-trimethoxybenzylidene)chroman-4-one (5), along with three known homoisoflavonoids (Z)-7-hydroxy-3-(4'-methoxybenzylidene)chroman-4-one (isobon ducellin) (2), (E)-7-hydroxy-3-(4'-methoxybenzylidene)chroman-4-one (bonducellin) (3) and (E)-7-hydroxy-3-(2',4'-dimethoxybenzylidene)chroman-4-one (4) were isolated from the whole plant of Caesalpinia pulcherrima. The structures of these new compounds were elucidated by electron impact mass spectrometry (EI-MS) and 1D and 2D-NMR spectral studies. Antimicrobial activity of the new compounds was evaluated.

A series of four naturally occurring homoisoflavonoids and eight analogs have been synthesized starting from an appropriately substituted phenol through chroman-4-one, in four steps. The products were assigned as E-isomers based on NMR spectroscopic data. The E-isomers were converted into Z-isomers by photoisomerization. The E- and Z-isomers showed distinct chemical shifts and the differences between (E) and (Z)-homoisoflavonoids in the proton NMR spectra afford a useful method for ascertaining the stereochemistry. The antioxidant activity of homoisoflavonoids was determined by superoxide (NBT) and DPPH free radical scavenging methods. The analog 7-hydroxy-3-[(3,4,5-trihydroxyphenyl)methylene]chroman-4-one displayed excellent activity followed by sappanone A in both the methods and were several times potent than the commercial antioxidants like BHA, BHT, etc. These compounds were evaluated in vitro for their inhibitory activities against 5-lipoxygenase (5-LOX) enzyme. The analog 7-hydroxy-3-[(N,N-dimethylaminophenyl)methylene]chroman-4-one was found to possess potent inhibitory activity and was comparable to that of the standard, nordihydroguiaretic acid. These results suggest that these homoisoflavonoids, with their potent antioxidant and 5-LOX inhibitory activities, may have useful applications as antioxidants and lead compounds for asthma and inflammatory diseases.

Two new 5-deoxyflavonoids, 7,2',3',4'-tetramethoxyflavone (1) and 7,2',3',4'-tetramethoxyflavanone (2) together with a known flavone 7,4'-dimethoxy-3'-hydroxyflavone (3) were isolated from the whole plant of Calliandra inermis. The structures of these new compounds were elucidated by high resolution electron impact mass spectrometry (HR-EI-MS) and 1D and 2D-NMR spectral studies including 1H-1H correlation spectroscopy (COSY), heteronuclear single quantum coherence (HSQC), heteronuclear multiple bond connectivity (HMBC) and nuclear Overhauser enhancement spectroscopy (NOESY).