Mono or double Pd-catalyzed C-H bond functionalization for the annulative π-extension of 1,8-dibromonaphthalene: a one pot access to fluoranthene derivatives.

The Pd-catalyzed annulative π-extension of 1,8-dibromonaphthalene for the preparation of fluoranthenes in a single operation has been investigated. With specific arenes such as fluorobenzenes, the Pd-catalyzed double functionalization of C-H bonds yields the desired fluoranthenes. The reaction proceeds via a palladium-catalyzed direct intermolecular arylation, followed by a direct intramolecular arylation step. As the C-H bond activation of several benzene derivatives remains very challenging, the preparation of fluoranthenes from 1,8-dibromonaphthalene via Suzuki coupling followed by intramolecular C-H activation has also been investigated to provide a complementary method. Using the most appropriate synthetic route and substrates, it is possible to introduce the desired functional groups at positions 7-10 on fluoranthenes.

Chemical Composition and Bioactivities of Quercus canariensis Flour Acorns Extracts Growing in Tunisia.

The current study was conducted to investigate the chemical composition of Quercus canariensis flour acorns extracts as well as its biological activities in regards to the growing area using spectrophotometric and chromatographic techniques. The phenolic profile was composed of 19 compounds identified through HPLC-DAD analysis. Coumarin was the most abundant compound quantified in BniMtir, Nefza and ElGhorra and gallic (12.58-20.52 %), syringic (4.70-7.64 %) and trans-ferulic (2.28-2.94 %) acids were the abundant phenolic acids while kaempferol was the major flavonoid compounds quantified only in Quercus canariensis growing in BniMtir. On the other hand, Ain Snoussi acorn extract was characterized by its high content in luteolin-7-O-glucoside (58.46 %). The in-vitro antioxidant activities of the studied extracts were investigated and the results showed that Nefza ethanolic extract's has the highest activities. A bactericidal effect against Staphylococcus aureus was observed only by Elghorra population. On the other hand, Ain Snoussi acorn extract was efficient to inhibit growth of pathogenic bacteria, mentioned the highest activity against Escherichia coli. These results is the first study highlighted that zeen oak acorns are an excellent source of natural antioxidants and antibacterial compounds related to their lysozyme activity which could be exploited in the pharmaceutical and food sectors.

Antibacterial, antibiofilm and cytotoxic properties of prodigiosin produced by a newly isolated Serratia sp. C6LB from a milk collection center.

The aim of this work was to produce a red tripyrrole pigment prodigiosin from Serratia sp. C6LB strain, to investigate the promising antimicrobial properties on Gram-positive and Gram-negative bacterial strains. The research was also proposed to evaluate the antibiofilm activity on Staphylococcus epidermidis S61 biofilm and its cytotoxic activity against human cancer cell lines. The production and structural elucidation of prodigiosin was carried out using spectrophotometric scanning, TLC, HPLC, FTIR and NMR analysis. The pigment production was optimized using mannose and peptone as carbon and nitrogen sources, respectively. The study confirmed promising antibacterial properties of prodigiosin on eight Gram-positive and Gram-negative bacterial strains with MICs values ranged from 0.039 to 2.5 mg/mL. Antiadhesive activity test of prodigiosin on Staphylococcus epidermidis S61 biofilm exhibited 99.9% inhibition, whereas maximum biofilm eradication activity reached 65%. Cytotoxic activity showed IC50 of 16 µg/mL and 6.7 µg/mL against breast cancer lines MCF-7 and MDA-MB231, respectively.

Tunisian Native Mentha pulegium L. Extracts: Phytochemical Composition and Biological Activities.

Mint species (Lamiaceae family) have been used as traditional remedies for the treatment of several diseases. In this work, we aimed to characterize the biological activities of the total phenolic and flavonoid contents of Mentha pulegium L. extracts collected from two different regions of Tunisia. The highest amounts of total phenols (74.45 ± 0.01 mg GAE/g DW), flavonoids (28.87 ± 0.02 mg RE/g DW), and condensed tannins (4.35 ± 0.02 mg CE/g DW) were found in the Bizerte locality. Methanolic leaf extracts were subjected to HPLC-UV analysis in order to identify and quantify the phenolic composition. This technique allowed us to identify seven phenolic compounds: two phenolic acids and five flavonoid compounds, such as eriocitrin, hesperidin, narirutin, luteolin, and isorhoifolin, which were found in both extracts with significant differences between samples collected from the different regions (p < 0.05). Furthermore, our results showed that the methanolic extract from leaves collected from Bizerte had the highest antioxidant activities (DPPH IC50 value of 16.31 µg/mL and 570.08 µmol Fe2+/g, respectively). Both extracts showed high radical-scavenging activity as well as significant antimicrobial activity against eight tested bacteria. The highest antimicrobial activities were observed against Gram-positive bacteria with inhibition zone diameters and MIC values ranging between 19 and 32 mm and 40 and 160 µg/mL, respectively. Interestingly, at 10 µg/mL, the extract had a significant effect on cell proliferation of U87 human glioblastoma cells. These findings open perspectives for the use of Mentha pulegium L. extract in green pharmacy, alternative/complementary medicine, and natural preventive therapies for the development of effective antioxidant, antibacterial, and/or antitumoral drugs.

Reactivity of bromoselenophenes in palladium-catalyzed direct arylations.

The reactivity of 2-bromo- and 2,5-dibromoselenophenes in Pd-catalyzed direct heteroarylation was investigated. From 2-bromoselenophene, only the most reactive heteroarenes could be employed to prepare 2-heteroarylated selenophenes; whereas, 2,5-dibromoselenophene generally gave 2,5-di(heteroarylated) selenophenes in high yields using both thiazole and thiophene derivatives. Moreover, sequential catalytic C2 heteroarylation, bromination, catalytic C5 arylation reactions allowed the synthesis of unsymmetrical 2,5-di(hetero)arylated selenophene derivatives in three steps from selenophene.

Effect of geographical origin on the chemical characteristics of Q. canariensis acorns: profiling fatty acids, tocopherols, and phenolic composition.

The impact of geographical origin on the chemical composition of acorns from Quercus species has significant attention. This study aimed to explore the phenolic composition of methanolic extracts, tocopherol content, and fatty acid composition of acorn oils from six different populations of Q. canariensis acorns. The obtained results revealed that acorn oil from BniMtir exhibited high levels of α-tocopherol (58 mg/kg). The fatty acids identified across all samples were Z-vaccenic + oleic acids (38.44-58.58%). In addition, the data highlighted the presence of quinic (32.514-60.216 µg/g DW) and gallic acids (1.674-10.849 µg/g DW), as well as catechin (+) (0.096-12.647 µg/g DW) in all populations. These variations in chemical composition from different regions are likely linked to their geographical origin. In conclusion, this study's finding should significance for the industry, offering valuable insights into the potential production of bioactive compounds from Q. canariensis acorns, which could have various applications.

3-Amino-4-(1,3-benzoxazol-2-yl)-5-(cyclo-hexyl-amino)-thio-phene-2-carbo-nitrile.

In the title compound, C18H18N4OS, the cyclo-hexyl ring adopts a chair conformation. The other rings of this compound lie almost in the same plane, with a mean deviation of 0.03 (2) Šfrom the least-squares plane defined by the 14 constituent atoms. There are intra-molecular N-H⋯N and N-H⋯O hydrogen bonds, as well as inter-molecular N-H⋯N hydrogen bonds, which link the mol-ecules into centrosymmetric dimers.

Influence of physico-chemical treatment on the subsequent biological process treating paper industry wastewater.

The present paper presents the main results of the biodegradation study of paper industry wastewater through physico-chemical treatment. Indeed, around 60% of chemical oxygen demand (COD) removal can be achieved by electroflocculation treatment. Furthermore, a removal efficiency of the COD of almost 91% has been obtained by biological treatment, with activated amount of sludge for 24 h of culture. Concerning the physico-chemical pre-treatment of the untreated, filtered and electroflocculated rejection effluents, it has been investigated through the degradation curve of COD studies.

Phenolic profile (HPLC-UV) analysis and biological activities of two organic extracts from Echinops spinosissimus Turra roots growing in Tunisia.

Echinops spinosissimus Turra subsp. roots was investigated, after extraction with two different solvents: ethanol and ethyl acetate, for its phenolic profile as well as biological activities. Echinops spinosissimus Turra subsp. spinosus roots ethanolic extract was characterized by the highest content of total polyphenols (19.3 mg GAE/100 g of DW). In addition, the phenolic profiles of the two studied extracts were analysed using HPLC-UV, where p-coumaric (8.59 mg/kg of DW) and cinnamic acids (4.68 mg/kg of DW) were detected as the most abundant phenolic acids, and kaempferol was the predominant flavonoids (30.37 mg/kg of DM) followed by quercetin and rutin in the ethanolic extract. While, only p-coumaric acid, epicatechin, kaempferol and quercetin were identified and quantified in ethyl acetate roots extract. All tested extracts exhibited an antimicrobial effect against Gram-positive and Gram-negative bacteria. These findings indicate that Echinops spinosissimus Turra subsp. spinosus roots can be regarded as a new source of edible oil having health benefits and nutritional properties.

Identification and quantification of phenolic and fatty acid profiles in Pinus halepensis mill. seeds by LC-ESI-MS and GC: Effect of drying methods on chemical composition.

This study aimed to evaluate Pinus halepensis Mill. seeds oil as well as methanolic-aqueous extract on fatty acid and phenolic's composition as well as antioxidant activities with regard to the cones drying methods: convection and sun methods. The highest amounts of total phenols (14.63 ± 0.05 mg GAE/g DW), flavonoids (3.3 ± 0.02 mg QE/g DW), and condensed tannins (0.36 ± 0.05 mg CE/g DW) were showed in the seeds obtained by sun-dried method. Methanolic-aqueous seeds extracts were subjected to LC-ESI-MS analysis in order to identify and quantify the phenolic composition. This technique allowed us to identify eleven phenolic compounds: two phenolic acids and nine flavonoid compounds such as cirsiliol, catechin (+), luteolin, and luteolin-7-O-glucoside, which were present in the two studied samples while apigenin, naringenin, and cirsilineol were only identified in the extract obtained from sun-drying method seeds. The chemical components of the oils were analyzed using GC, and significant differences were found between the two studied seeds oil (p < .05). Furthermore, the antioxidant activities were investigated using DPPH and ABTS.+ assays. The results showed that the methanolic-aqueous extract from seeds dried by sun method had the highest antioxidant activities (0.08 and 0.05 mg/ml, respectively). This study could provide useful information for industry to produce potentially bioactive plant extract.

Phenolic content, antioxidant capacity and antimicrobial activity of leaf extracts from Pistacia atlantica.

The aim of this study was to investigate the secondary metabolites related to Pistacia atlantica Desf as well as their biological activities. Results show that using ethanol as a solvent exhibited the highest content of total phenolics and flavonoids (68.23 mg GAE g-1 of DW and 44 mg RE g-1 of DW), followed by aqueous one (20.07 mg GAE g-1 of DW and 15 mg RE g-1 of DW). Good correlation (Data not shown) was obtained between the DPPH radical-scavenging activities and total phenolics contents. Many similarities were observed between the results of the DPPH (IC50 = 32 and 200 µg mL-1) and ABTS (IC50 = 42 and 300 µg mL-1) assays. All tested extracts contained phenolic compounds exhibited an antimicrobial effect against Gram-positive and Gram-negative bacteria. Further, researches for identification and purification of phenolic compounds are required.

Gold-Catalyzed Suzuki Coupling of ortho-Substituted Hindered Aryl Substrates.

A method that allows hindered ortho-substituted aryl iodides to be efficiently coupled to phenylboronic acid using a gold-catalyzed C-C bond formation is presented. The use of a molecularly-defined dinuclear gold chloride catalytic precursor that is stabilized by a new tetradentate (N,N')-diamino-(P,P')-diphosphino ferrocene hybrid ligand in a Suzuki-type reaction is described for the first time. Electron-rich isopropyl groups on phosphorus were found essential for a superior activity, while the performances of a set of analogous gold dinuclear complexes that were fully characterized by multinuclear NMR spectroscopy and XRD analysis, were investigated. Therefore, arylation of para and ortho-substituted iodoarenes bearing electron-rich, electron-poor functional groups, and even hindered polycyclic aromatic compounds is described.

Recovery of hydroxytyrosol rich extract from two-phase Chemlali olive pomace by chemical treatment.

UNLABELLED: A very simple method is proposed to produce hydroxytyrosol, a commercially unavailable compound with well-known biological properties which justify a potential commercial application. The 2-phase Chemlali olive pomace is selected as substrate for chemical treatment. Different conditions of chemical treatment, including concentration of acid and alkaline solutions, time and temperature, were assayed. A high amount of hydroxytyrosol (1360 mg/kg of fresh 2-phase olive pomace) was obtained using water bath after treatment at 80 °C for 90 min with 1 M of H(3) PO(4) . However, treatment of 2-phase Chemlali olive pomace using autoclave apparatus could produce a large amount of hydroxytyrosol (1993.60 and 1515.88 mg/kg of fresh alperujo, 1 M acid and basic catalyst, respectively). By taking into consideration practical and economic aspects, acid-catalyzed treatment was more effective using autoclave conditions, whereas the alkali catalyzed conditions were not very suitable. This study could provide useful information for industry to produce the potentially bioactive compound. PRACTICAL APPLICATION: The 2-phase Chemlali olive pomace is selected as substrate for chemical treatment. Treatment of "alperujo" using water bath or autoclave apparatus was carried out. A high amount of hydroxytyrosol was obtained using autoclave apparatus.

Ultrasonic activation of Heck type reactions in the presence of Aliquat-336.

Without phosphine and base, palladium catalysts such as PdCl(2), Pd(OAc)(2) and PdCl(2)(PhCN)(2) in water/DMF mixtures with Aliquat-336 proved to be excellent catalytic systems for Heck reactions involving several aryl bromides with styrene and acrylic compounds. Yields are remarkably improved under ultrasonic irradiation and the products show a high purity.

Phenolic composition, isolation, and structure of a new deoxyloganic acid derivative from Dhokar and Gemri-Dhokar olive cultivars.

Two rare olive cultivars, Dhokar and Gemri-Dhokar, growing in the south of Tunisia were investigated to identify their phenolic profile and evaluate their sugar content and antioxidant activity. The highest value of phenolic content was detected in Gemri-Dhokar cultivar extract (6.97 g gallic acid equivalents/kg of fresh olive). In addition, sugar content was quantified; glucose (45.17 g/kg of fresh olive) was the predominant sugar in Dhokar cultivar, followed by fructose (40.83 g/kg of fresh olive). The identification of phenolic compounds was based on separation by high-performance liquid chromatography equipped with a diode array detector followed by liquid chromatography-mass spectrometry analysis. In both cultivars, Oleuropein aglycon derivatives and elenolic acid were the main phenolic components. Oleuropeins were the major compounds quantified in the Gemri-Dhokar drupes olives (61.04 mg/100 g of fresh olive), while 0.25 mg/100 g were found in fresh Dhokar. A new iridoid compound, isolated as pure compound, was not previously reported in the literature. Its structure was established by spectroscopic analyses (NMR, UV, MS, and IR). DPPH, ABTS, and FRAP assays showed that the most important antioxidant capacity of olive extracts was found in with Gemri-Dhokar cultivar.