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Employing plant extracts to obtain nanomaterials is an ecofriendly and highly appreciated synthetic approach. In this work a simple, green chemistry method, based on sol–gel, was used for ZnO nanoparticles synthesis by using two Sudanese medicinal plant extracts: Adanosia digitata (ZnO-A) and Balanites aegyptiaca (ZnO-B) under ultrasonic energy. The X-ray diffraction (XRD) revealed the formation of wurtzite hexagonal ZnO nanostructures, while the scanning electron microscopy (SEM) analysis displayed their diverse morphologies. The X-ray photoelectron spectroscopy (XPS) data showed the impact of extract via the variation in of the O1s and Zn2p3/2 and Zn2p1/2 orbitals binding energy of Zn–O. The UV-visible investigation indicated a variation of bandgap energy (E g ), where the ZnO nanoparticles displayed the lowest E g . The synthesized nanomaterials have exhibited high photocatalytic efficiency towards the methylene blue (MB) dye. The findings revealed the possibility of obtaining nanoparticles with tailored properties by using plants extracts.

The photodegradation of Congo red dye by (Y2O3)n ZnO photocomposites was investigated through a sequence of experiments. X-ray diffraction analysis indicates nanocomposites' evolution having the ZnO wurtzite structure with increase in crystallite size and Y2O3 phase segregation, as confirmed by the appearance and gradual growth of the Y2O3 peak. Field emission scanning electron microscopy observations reveal irregular spherical morphology with increased agglomeration due to Y2O3 loading. Diffuse reflectance spectra exhibit bandgap widening and red shift of the absorption edge with the doping process. Brunauer–Emmett–Teller analysis denotes improved porosity as manifested by the surface area, pore diameter, and pore volume increments after yttrium loading. Fortuitously, photocatalysts demonstrate excellent photodegradation rates for CR dye, reaching 93% at a higher rate of 43 × 10–3 min−1. The photocomposite 1% Y2O3–ZnO exhibits a threefold enhancement in the visible photocatalytic process in an aqueous solution. The photocatalytic performance is discussed in detail concerning pH and oxygen species, which contribute to the photodegradation of CR dye. The results obtained in this study clearly highlight the superior performance (Y2O3)n ZnO as a highly efficient photocatalyst in the degradation of dyes in water.

The objective of the research is to evaluate the concentrations of some metallic elements (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn) in the fallen dust (resulting from dust storm) because they have a ...

Ba-doped ZnO nanostructures (0.8–4 mmol) were successfully fabricated by the co-precipitation method. X-ray diffraction analysis indicated that all samples exhibited a typical hexagonal wurtzite ZnO structure with the emergence of BaO phase. Moreover, the incorporation of Ba resulted in an increase of crystallite size and lattice parameter while microstrain decreases. The broadening of the Zn–O vibrational band and the redshift in Raman vibrational modes provided clear evidence of the incorporation of Ba within ZnO host lattice. Furthermore, Ba doping prompted an increase of the dielectric constant and ac conductivity (σac). Additionally, the subsequent decrease in tangent loss with increasing the applied field frequency was associated with the hopping frequency of electron that enhances the charge carriers’ mobility.

The synthesis of metallo-phthalocyanines complexes (M = Co, Ni, Cu, Zn) containing azo dye were described in this study. The metallophthalocyanines have been supported by elemental analysis, UV-visible, FT-IR and NMR. The aggregation of phthalocyanine compounds was investigated in different solvents and concentrations. The newly synthesized metallophthalocyanines possess modest antibacterial activity against various Gram-positive and Gram-negative bacteria. Moreover, these complexes have been tested as antioxidant and presented remarkable activities by two different in vitro chemical assays. They were able to reduce DPPH % radical with IC50 values ranging from 3.8 to 7.5 μmol L-1 and some of them also reduced ABTS % radical cation.

The synthesis and metal-ion complexation properties of two new derivatives of 1,3-di(carboxymethyl)-p-tert-butylcalix[4]arene, bis(2-thienylmethylamide) 3 and bis(furanylmethylamide) 4, have been studied using UV/Vis spectrophotometry and, in some cases, 1H-NMR spectroscopy. The cations examined are alkali metals (Li+, Na+, K+, Rb+ and Cs+), alkaline earth metals (Mg2+, Ca2+, Sr2+ and Ba2+), heavy metals (Ag+, Cd2+, Hg2+ and Pb2+), and lanthanides (La3+, Nd3+, Eu3+, Gd3+ and Yb3+).

New palladium complexes were efficiently synthesized from the reaction of benzimidazolium salts 2a–e, potassium carbonate (K2CO3) and palladium chloride (PdCl2) in pyridine (for 3a–e). The catalyti...

The flavone C-glycosides namely apigenin-7-O-β- d -glucopyranosyl-8-C-β- d -glucopyranoside (1) and apigenin-8-C-α- l -rhamnopyranosyl-(1→2)-O-β- d -glucopyranoside (2), along with p-methoxycinnamic acid (3), vaccaroside A (4), vaccaroside D (5), vaccaroside E (6) and abscisic acid glucose ester (7) were isolated from the methanol extract of the aerial parts of Vaccaria pyramidata. Structure elucidation of compounds 1-7 was accomplished by the extensive use of 1D- and 2D NMR experiments along with HR-ESI-MS. The structures of 1-2 have been confirmed by theoretical study of the 1H, 13C chemical shifts and UV data. In addition, Ionization Potential (IP) and Bond Dissociation Enthalpy (BDE) were used to evaluate the theoretical antioxidant activity of compounds 1 and 2. TD-DFT method (time-dependent density functional) was used to calculate the electronic absorption spectra of compounds 1 and 2 from optimized structures in methanol and the orbitals involved in the electronic transition were elucidated.

The carbonylative Suzuki cross-coupling of 2-bromopyridine with various boronic acids to prepare unsymmetrical arylpyridine ketones has been carried out using palladium/N-heterocyclic carbene complexes as catalysts prepared in situ. The selectivity and the rate of these reactions are highly dependent on the conditions, i.e., nature of the palladium catalyst precursor, solvent, temperature and CO pressure. The main side-products arise from direct, non-carbonylative cross-coupling. Under the optimum conditions, arylpyridine ketones are recovered in high yields (60–88%). The antibacterial activities of the corresponding benzimidazole salts 2 were tested against Gram positive and negative bacteria using the agar dilution procedure, and their IC50 values have been determined.

The purpose of this study is to know the concentrations of some heavy-metal elements (Zn, Pb and Cd) in different types of soil and the effect of pH values on their solubility. Two types of soil we...

N,N-Substituted benzimidazole salts were successfully synthesized and characterized by 1H-NMR, 13C {1H} NMR and IR techniques, which support the proposed structures. Catalysts generated in situ were efficiently used for the carbonylative cross-coupling reaction of 2 bromopyridine with various boronic acids. The reaction was carried out in THF at 110 °C in the presence of K2CO3 under inert conditions and yields unsymmetrical arylpyridine ketones. All N,N-substituted benzimidazole salts 2a–i and 4a–i studied in this work were screened for their cytotoxic activities against human cancer cell lines such us MDA-MB-231, MCF-7 and T47D. The N,N-substituted benzimidazoles 2e and 2f exhibited the most cytotoxic effect with promising cytotoxic activity with IC50 values of 4.45 μg mL−1 against MDA-MB-231 and 4.85 μg mL−1 against MCF7 respectively.

Medemia argun is an ancient endemic palm growing in Nubian Desert of Egypt and Sudan. Liquid chromatography coupled with mass spectrometry in negative ion mode (LC/ESI-MS) has proved to be a potent tool for rapid identification and characterization of complex phytochemicals in male racemes of M. argun . A total of seven compounds were tentatively identified comprising of two C-glycoside acetophenones, along with the known compounds one stilbene derivative and four known flavonol derivatives from 40% methanolic portion. The product ions of acetophenone derivatives [M−H] – were shown to be cross-ring cleavages of the hexoside moiety [M-(90/120)-H] – characteristic for C-glycoside linkage. The position of C C -linkage was elucidated by DFT study using the Fukui functions and descriptors. The results revealed that hexose was conjugated with aglycones at C3 or C5. In addition, the theoretical antioxidant activity of compounds 6 and 7 was evaluated by using Bond Dissociation Enthalpy (BDE).

Background α-Methylene cycloalkanones are considered of interest because of their biological activity. Herein, in this paper the synthesis of (±) HomoSarkomycine Esters was described and characterized. Methods Using Bylis-Hillman adducts, triethlorthoacetate and propanoic acid, (±) HomoSarkomycine Esters could be synthesized by smoothly Johnson-Claisen rearrangement. Results A small library of target compounds was prepared under optimized reaction conditions in moderate yields. The reaction mechanism and the DFT study have been investigated. Conclusion This methodology provides ready access to 2-hydroxymethyl-2-cyclopentenone 1a which can be served as the raw materials of the synthesis of (±) HomoSarkomycine Ester.

A series of ruthenium(II) complexes with N-heterocyclic carbene ligands were successfully synthesized by transmetalation reactions between silver(I) N-heterocyclic carbene complexes and [RuCl2(p-cymene)]2 in dichloromethane under Ar conditions. All new compounds were characterized by spectroscopic and analytical methods. These ruthenium(II)–NHC complexes were found to be efficient precatalysts for the transfer hydrogenation of ketones by using 2-propanol as the hydrogen source in the presence of KOH as a co-catalyst. The antibacterial activity of ruthenium N-heterocyclic carbene complexes 3a–f was measured by disc diffusion method against Gram positive and Gram-negative bacteria. Compounds 3d exhibited potential antibacterial activity against five bacterial species among the six used as indicator cells. The product 3e inhibits the growth of all the six tested microorganisms. Moreover, the antioxidant activity determination of these complexes 3a–f, using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azinobis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS) as reagent, showed that compounds 3b and 3d possess DPPH and ABTS antiradical activities. From a concentration of 1 mg ml−1, these two complexes presented a similar scavenging activity to that of the two used controls gallic acid (GA) and butylated hydroxytoluene (BHT). From a concentration of 10 mg ml−1, the percentage inhibition of complexes 3b and 3d was respectively 70% and 90%. In addition, these two Ru–NHC complexes exhibited antifungal activity against Candida albicans. Investigation of the anti-acetylcholinesterase activity of the studied complexes showed that compounds 3a, 3b, 3d and 3e exhibited good activity at 100 μg ml−1 and product 3d is the most active. In a cytotoxicity study the complexes 3 were evaluated against two human cancer cell lines MDA-MB-231 and MCF-7. Both 3d and 3e complexes were found to be active against the tested cell lines showing comparable activity with examples in the literature.

The aim of this study was to characterize minor lipids in methanol fraction extracted from raw camel milk after loading it on a water-preconditioned short C18 open column and fractionating with a gradient of methanol/water. The C18 column showed high fractionation efficiency of minor lipids, such as glycosphingolipids, lipopolysaccharides, or oligosaccharides, when compared with other constituents, in particular polysaccharides, proteins, and free fatty acids. Liquid chromatography electrospray ionization tandem mass spectrometry in negative ion mode was used to identify 21 new glycosphingolipids, lipopolysaccharides, and oligosaccharides. Electrospray ionization tandem mass spectrometry was qualified to provide relevant data for recognizing the molecular mass, glycosylation sequences, and structure of saccharide moieties for the revealed compounds. The sequence of combinations of one selected lipopolysaccharide, which was considered the backbone of the remaining lipopolysaccharides, was confirmed in a density functional theory study. The obtained results showed that the tested fraction is a rich source of glycosphingolipids, lipopolysaccharides, and oligosaccharides with antioxidant activity.

This study was undertaken to determine the antibacterial efficacy of the essential oil (EO) of peppermint (Mentha piperita L.), in vitro and in vivo, against the phytopathogenic bacteria Agrobacterium tumefaciens (A. tumefaciens). The EO composition of M. piperita L. was investigated by Gas chromatography-mass spectrometry (GC/MS) with 26 identified volatile constituents. The major constituents were menthol (33.59%) and iso-menthone (33.00%). This EO exerted a bactericidal activity against multiple strains of Agrobacterium species with minimum inhibitory concentration (MIC) values ranged from 0.01 to 12.50 mg/mL. In planta experiments, M. piperita EO, tested at concentration of 200 mg/mL, completely inhibited the formation of tumors on tomato plants inoculated with pathogenic strain A. tumefaciens ATCC 23308

A series of novel benzimidazolium salts 2 and their new air and moisture stable PEPPSI type N-heterocyclic carbene palladium(II) complexes (PEPPSI: pyridine-enhanced pre-catalyst preparation, stabilisation, and initiation), were synthesized and characterized by means of 1H and 13C{1H} NMR, FTIR spectroscopic methods and elemental analysis was employed to catalyze the Mizoroki-Heck cross-coupling reactions of aryl bromides with styrene in water. To the best of our knowledge, this is the first report where a Pd-PEPPSI catalyst was successfully employed in aqueous-phase Mizoroki-Heck reaction. Good to excellent yields of cross-coupling products were obtained with a range of representative aryl bromides under relatively mild conditions. Moreever the antimicrobial activity of the PEPPSI type N-heterocyclic carbene palladium(II) complexes 3a-e varies with the nature of the ligands. Also, the IC50 values of both, complexes (3a-e) have been determined. In addition, the new PEPPSI type N-heterocyclic carbene palladium(II) complexes were screened for their cytotoxic activities. Complex 3b exhibited the highest antitumor effect with IC50 values 0.63 μg/mL and against MCF-7.

In this study, a simple and eco-friendly method based on a used pectinose solution is described for the fabrication of a RuO2-ZnO photo-composite at different annealing temperatures. Characterization of the phase structure, morphology, and elemental composition confirms that the synthesized RuO2-ZnOcomposite has a hexagonal wurtzite-type structure of the ZnO phase with three extra peaks related to the formation of the RuO2 rutile phase, delineating at the (110), (101) and (211) crystal planes. The SEM and TEM result of RuO2-ZnO at Tc = 700 °C has clearly revealed the formation of nanorods shaped. The hysteresis loop RuO2-ZnO was type H3 and in the range of 0.05–1.0 relative pressure which is representative of a mesoporous nanomaterial. The photocatalytic performance of the prepared photo- composite is evaluated for indigo carmine dye degradation under visible light. The photodegradation of the dye follows first-order kinetics and the rate constant is estimated to be 36.38 × 10−3 min−1 for RuO2-ZnO annealed at 700 °C. This work provides novel insights for the synthesis and formation of RuO2-ZnO photo-composites, which can be applied in photocatalysis for removal of the pollution of water.

We report here the facile synthesis of a new series of hydroxy-thioxo-imidazole carboxylates in good yields using the cyanomethyl anion as an electrogenerated base which is formed when dry acetonitrile is electrolyzed at constant current, followed by addition of different thioureas and diazirine-3,3-dicarboxylate. The mechanism of the reaction, NMR shifts and IR are discussed and compared to density functional theory calculations.

Pd(II)-bis(NHC) complexes (where NHC = N-heterocyclic carbene) bearing asymmetrically and symmetrically substituted NHC-ligand have been synthesized via deprotonation of 5,6-dimethylbenzimidazolium salts. The NHC precursors have been achieved via the two step N-alkylation of 5,6-dimethylbenzimidazole. The resultant salts were deprotonated with PdCl2 and K2CO3 in dry THF for 2(a–e). The obtained complexes were identified and characterized by 1H and 13C NMR, FT-IR, DART-TOF mass spectrometry and elemental analysis. These new Pd(II)-bis(NHC) complexes were applied as catalyst precursors for Suzuki-Miyaura cross-coupling reactions of aryl bromides and chlorides with phenylboronic acid to afford the corresponding products in good yields. This catalytic reaction was evaluated in the presence of KOtBu/toluene. The antibacterial activities of 2(a–e) were investigated against Gram (+)/(−) bacteria using the agar dilution procedure. The antibacterial activities of 2 vary with the nature of the ligands; MIC values of 2(a–e) were determined.

The interaction of the benzimidazolium salt with Ag2O in dichloromethane to prepare novel Ag(I)-N-heterocyclic carbene complexes has been carried out at room temperature for 48 h in the absence of light. The obtained complexes were identified and characterized by 1H and 13C NMR, FT-IR and elemental analysis techniques. In addition, it has been found that some of the complexes are antimicrobially active and show higher activity than the free ligand. Probably metal chelation affects significantly the antimicrobial behavior of the ligands. The minimum inhibitory concentration of the complexes was determined. The results indicated that these complexes exhibit antimicrobial activity.

In the present paper, kinetics of alkaline degradation of well known drug, indomethacin (2-[1-(4-chlorobenzoyl)-5-methoxy-2-methylindol-3-yl]acetic acid), was studied in presence of excess [NaOH]. The rate of hydrolysis of substrate was independent of the [indomethacin] though it increased linearly with increasing the hydroxide ion concentration with a positive slope, suggesting the following rate law: kobs = k1[OH−]. Cationic surfactants having non-reactive ions (cetyltrimethylammonium bromide, CTAB and cetyltrimethylammonium sulfate (CTA)2SO4) first increased the rate constants at lower concentrations and then decreased it at higher concentrations while in case of the surfactant with reactive counterions (cetyltrimethylammonium hydroxide, CTAOH) the rate increases sharply at lower concentrations of surfactant until it reaches to a plateau in contrast to the appearance of maxima in case of CTAB and (CTA)2SO4. Anionic surfactant, sodium dodecyl sulfate (SDS), inhibited the reaction rate at all concentrations used in the study. Pseudophase ion-exchange model was used for analyzing the effect of cationic micelles while the inhibition by SDS micelles was fitted using the Menger–Portnoy model. The effect of salts (NaCl, NaBr and (CH3)4NBr) was also seen on the hydrolysis of indomethacin and it was found that all salts inhibited the rate of reaction. The inhibition followed the trend NaCl < NaBr < (CH3)4NBr.

Some new aminothieno[2,3-b]quinolinones and tacrine analogues derivatives were synthesized in high yield with acid activated bentonite as a catalyst via the Friedlander condensation reactions between 2-aminothiophene-3-carbonitrile and ketones. The structure elucidation of compounds was done by FT-IR, NMR spectroscopy and microanalytical elemental data.

The corrosion inhibition efficiency of carbon steel pipelines in 1M HCl by the synthesized hexatriethyleneamine derivatives potensiodynamic polarization 30 oC. The results showed that all synthesized inhibitors were good inhibitors and their inhibition efficiencies were significantly increased with increasing concentration. The surface activity were calculated from its surface tension measurements including the critical micelle concentration (CMC), effectiveness of surfactant (π), maximum surface excess (Γmax) and the minimum surface area (Amin).

The kinetics of autoxidation of adrenaline and [Cu(adrenaline)]2+ complex by dissolved oxygen in alkaline aqueous and micellar media has been studied. The reaction is initiated by the removal of amino-H+ protons of adrenaline by hydroxide ion, followed by cyclization. The values of (1/k obs) for the autoxidation of both species were found to be linearly dependent upon 1/[OH−]. The reaction follows a consecutive pathway in which the intermediate adrenochrome remains stable for few minutes, and then undergoes further reactions to yield adrenolutin and other products. The [Cu(adrenochrome)]+ complex is stable for a few hours. Studies on the effects of cetyltrimethylammonium bromide (CTAB) and sodium dodecyl sulfate (SDS) on the reactivity of both species revealed different behaviors. The micelles of CTAB catalyzed the rates of autoxidation for both species, whereas SDS micelles inhibited the autoxidation of adrenaline but catalyzed the rate of autoxidation of [Cu(adrenaline)]2+. Addition of the reactive counterion surfactant, cetyltrimethylammonium hydroxide (CTAOH) initially increased the rate constant with the increasing [CTAOH], until it reached a plateau for k ψ −[CTAOH]. Salts such as NaCl, NaBr, tetramethyl ammonium bromide, and tetraethyl ammonium bromide increased the rate when added at lower concentrations, but had negligible effect at higher concentrations. The results obtained in micellar media were treated according to Berezin’s Pseudophase Model. The various kinetic parameters for the reactions occurring in aqueous and in micellar media are reported.

The alkaline hydrolysis of carsalam (2H-1,3-benzoxazine-2,4(3H)-dione), denoted as I, and its N-substituted derivatives i.e., N-methyl-1,3-benzoxazine-2,4-dione (II) and N-benzoyl-1,3-benzoxazine-2,4-dione (III) was studied spectrophotometrically at physiological temperature. The rate of hydrolysis was found to be independent on the substrate concentration. In case of I, the reaction was fractional order with respect to [OH(-)] while for II and III, reaction obeyed the first order kinetics. Effect of cationic surfactants with varying hydrophobic chains (cetyltrimethylammonium bromide, CTAB, tetradecyltrimethylammonium bromide, TTAB and dodecyltrimethylammonium bromide, DTAB) and with different head-group (cetyl pyridinium chloride, CPC) and anionic surfactant (sodium dodecyl sulfate, SDS) was also seen on the rate of alkaline hydrolysis of the carsalam and its derivatives. Cationic surfactants first catalyzed the rate of hydrolysis at lower concentrations followed by the inhibition at higher concentrations. The length of the alkyl chain had remarkable effect on the catalytic efficiency of the surfactants. Similarly N-substitution on substrate also increased the catalysis by micelles. The anionic surfactant SDS inhibited the rate of hydrolysis at all of the concentrations studied. The catalysis by cationic micelles followed by inhibition was treated in terms of the pseudophase ion-exchange model, while for the inhibition by SDS micelles the Menger-Portnoy model was used to fit the data. The effect of salts (NaCl, NaBr and (CH(3))(4)NBr) was also seen on the hydrolysis of II and it was found that all salts inhibited the rate of reaction. The inhibition follows the trend NaClNaBr(CH(3))(4)NBr.

3-((2E)-3(aryl)prop-2-enoyl)-2H-chromen-2-one 3 was synthesized from 4-hydroxy coumarin by refluxing 3-acetyl-4-hydroxy coumarin with aromatic aldehydes in chloroform in the presence of a catalytic amount of piperidine. 3 was converted to pyrazoles 4, 5 by treatment with hydrazine and phenylhydrazine in toluene, respectively. The structures of the new compounds were confirmed by elemental analysis, IR, and multinuclear/multidimensional NMR spectroscopy (1H, 13C-NMR, NOESY, HMBC) which allowed us to assign the complete network of proton and carbon atoms. All the compounds exhibited one quasireversible redox process. All the newly synthesized compounds were screened for their antibacterial and antioxidant activities. Antimicrobial studies revealed that 3-(5-(2,5-dimethylphenyl)-1-phenyl-4,5-dihydro-1H-pyrazol-3-yl)-4- hydroxy-2H-chromene-2-one 5c showed significant antibacterial activity against Escherichia coli and Pseudomonas Aeruginosa 27853. Furthermore, 3-(5-(aryl)-4,5-dihydro-1H-pyrazol-3-yl)-4-hydroxy-2H-chromene- 2-ones 4, 5 showed antioxidant activities of different extents with respect to individual compounds as well as to the antioxidant methods. The 3-(5-(phenyl)-4,5-dihydro-1H-pyrazol-3-yl)-4-hydroxy-2H-chromene-2-ones 4a was found to be the most active antioxidant in the series and more active than trolox which makes the investigated complexes a new promising class of antibacterial compounds.

Cobalt (Π), Nickel (Π) and Copper (Π) complexes, with Schiff base ligand derived from 1, 6- diaminohexane and salicyladehyde (salhex) have been synthesized and characterized by elemental analysis, conductance measurements, magnetic susceptibility measurements, IR, electronic spectra, ESR spectral studies and thermal analysis. IR spectra suggested that salhex acts as tetra dentate dibasic ligand. The possible geometries of the complexes are assigned on the basis of ESR, electronic spectra as well as the magnetic moment values. The thermal behaviour of Cu (Π) complexes is studied using thermogravimetric analysis (TGA) technique. The different thermodynamic and kinetic parameters are calculated using Coats-Redfern method.

This study aimed for the synthesis of 4-Aryl-2-amino-6-(4-hydroxy coumarin-3-yl) pyridine-3-carbonitriles derivatives 4, suitable for use as antibacterial, anti-oxidant and anti-inflammatory activities via a versatile, readily accessible 3-((2E)-3(aryl)prop-2-enoyl)-2H-chromen-2-one, 3, which was prepared by refluxing 3-acetyl-4-hydroxycoumarin with aromatic aldehydes in chloroform in the presence of a catalytic amount of piperidine. Then the direct reaction of the obtained chalcones 3 with malonitrile in the presence of ammonium acetate in one step gave products 4. Most of the new compound 4 exhibit moderate antibacterial activity against Gram Negative bacterial strains (E. coli, K. pneumonia, S. typhi and S. flexneri). In addition, the compounds 4 were investigated for anti-oxidant activities by super oxide radical, DPPH (2,2-Diphenyl-1-picrylhydrazyl), and hydroxyl radical scavenging assays, where most of the compounds displayed significant antioxidant activities. Furthermore, these 4-Aryl-2-amino-6-(4-hydroxy coumarin-3-yl) pyridine-3-carbonitriles 4 were evaluated for anti-inflammatory activity by indirect haemolytic and lipoxygenase inhibition assays where compounds revealed good activity. The preparation of novel metal-free phthalocyanines and metallophthalocyanine complexes 11 and 12 (MPcs, M = Co, Zn, Cu and Mn), with four peripheral 6-hydroxy-4-methylcoumarin and 6-hydroxycoumarin substituents, were also prepared by cyclotetramerization of compounds 7 and 10 with the corresponding metal salts (Zn(OAc)2.2H2O, Co(OAc)2.4H2O, CuCl, Mn(OAc)2.4H2O) as a template for macrocycle formation in 2-(N,N-dimethylamino)ethanol.The electronic spectra of these compounds exhibit a band of coumarin identity together with characteristic bands of the phthalocyanine core. The new compounds were screened for antibacterial activity. Most of them are active against E. coli and S. aureus. In addition, some novel 3-acetylcoumarin derivatives 17 were prepared in good yields. Their invitro antioxidant activities were assayed by the quantitative 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity method. In this way, novel coumarin phtalonitriles derivatives 42-44 were synthesized.The synthesis of these coumarin phtalonitriles was resulting from a nucleophilic aromatic substitution reaction between 4-nitrophtalonitrile and coumarins derivatives. The complexing properties of the coumarin derivatives toward alkali metal, alkaline earth metal, some transition metals and some heavy metal cations have been investigated in acetonitrile by means of UV spectrophotometry absorption and conductivity methods. Thus, the stoichiometry of the complexes formed and their stability constants were determined. We report also in this book chapter a sequence of two ruthenium-catalyzed transformations, namely olefin cross metathesis with allylic chloride followed by elimination, which gives a straightforward access to terminal 1,3-dienes from natural products. The structures of all the new obtained compounds were confirmed by elemental analysis, IR, and multinuclear/multidimensional NMR spectroscopy (1H, 13C-NMR, NOESY, HMBC) which allowed assignment of the complete network of proton and carbon atoms).

In this study, the synthesis and cross metathesis of o-eugenol (2-allyl-6-methoxy phenol) has been investigated. Synthesis was conducted through two stages of reaction. The first step in the synthetic procedure was to obtain the intermediate 1-but-3-enyl-2-methoxy benzene. Then the heating of the obtained intermediate will initiate will initiate a [3,3] sigmatropic rearrangement to give the o-eugenol with a good yield. The ruthenium-catalyzed cross-metathesis of o-eugenol derivatives with electron deficient olefins including methyl acrylate, acrylonitrile and acrylamides was also reported. In addition the polymerization of 1-allyl-2-(allyloxy)-3-methoxybenzene was possible by acyclic diene metathesis and this allowed to synthesize a polymer from a natural substrate. All the resulting structures were supported by the spectroscopic data.

The synthesis of a novel phthalonitrile derivative with pyridine-2-thiol and 2,4,6-trimethylphenylamine substituents functionalized groups and its peripherally tetrasubstituted cobalt phthalocyanine and cationic phthalocyanines complexes were reported. The aggregation investigations carried out in different concentrations indicate that Co Phthalocyanines compounds 3 , 4 do not have any aggregation behavior for the concentration range of 6 × 10 − 4 –14 × 10 − 6 M in DMSO. The ion binding properties of Co Phthalocyanines compounds 3 , 4 show the formation of stable complex with Co 2 + . In addition 3,4-Dihydropyrimidin-2(1H)-one derivatives were synthesized by modified Biginelli cyclocondensation reaction catalyzed by MPc as Lewis base. The structures of the synthesized compounds have been successfully characterized by the spectroscopic methods (IR, 1 H NMR, 13C NMR, UV–Vis, mass spectrometry, elemental analysis and NMR 2D). The influence of substrate/catalyst ratio, solvent was also investigated to find optimal reaction on this synthesis for getting the highest conversion. Different parameters were examined for finding optimal conditions of catalysis. In addition; the compounds 3–11 were investigated for antimicrobial activity. Most of them exhibited important antimicrobial activity.

Samh flour ( Mesembryanthemum forsskalei ) is a foodstuff with high protein content, which can be used as a replacement for wheat flour. It is often consumed by Bedouin tribes of northern Saudi Arabia. Very little is known about bioactive molecules present in samh flour, therefore we analyzed its extracts to evaluate the contents of secondary metabolites. A total of 43 secondary metabolites present in 60% MeOH extract of samh flour were tentatively identified using LC–ESI-MS/MS. These compounds represented five major categories: glucosinolates, sinapic acid and sinapoylglycosides, acylated flavonoids, flavonoids, and amide derivatives. Their effect on oxidative damage of proteins and lipids was determined in vitro by assessing levels of protein thiol groups and concentrations of thiobarbituric acid reactive species (TBARS) in human plasma. Obtained results indicated that samh flour is a rich source of compounds with antioxidant activity.

A new cyclobutane ring system related to plicatin B has been isolated from the methanol soluble fraction of Psoralea plicata seeds and named as -diplicatin B. In addition, the anti-repellent (-)-loliolide and phloretic acid ethyl ester [3-(4-hydroxyphenyl) propanoic acid ethyl ester) have been isolated from the same extract, their structures being determined on the basis of 1D ( 1 HNMR and 13 CNMR) and 2D (DQF-COSY, HMQC and HMBC) NMR and mass spectra. Stereoisomers of -diplactin B have been optimized by means of density functional theory using the hybrid functional B3LYP.

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2-Amino-3-ethoxycarbonyl-4-(aryl)-4H-pyrano-[3,2-c]-chromene-5-ones5is synthesized by the two-component reaction of 4-hydroxycouamrin with ethyl-2-cyano-3-(aryl) acrylate3. The structures of the obtained compounds are confirmed by analytical IR,1H, and13C-NMR spectra to elucidate the different positions of protons and carbons and as well as theoretic studies (DFT/B3LYP). All the newly synthesized compounds are screened for their antibacterial. Furthermore, these compounds showed antioxidant activities of different extents with respect to individual compounds as well as to the antioxidant methods. The compounds5a–ewere found to be the most active antioxidant in the series then Trolox, which makes the investigated complexes a promising new class of antibacterial activity compounds.

A new 4-hydroxy-3-carboxycoumarin ligand and its ruthenium(II) complexes (1–5) have been synthesized, characterized and screened for their in vitro antibacterial activity against a range of Gram-positive and Gram-negative bacteria. In addition, compounds 1–5 were investigated for antioxidant activities using superoxide radical, 2,2-diphenyl-1-picrylhydrazyl radical and hydroxyl radical scavenging assays, in which most of them displayed significant antioxidant activities. Furthermore, compounds 1–5 were evaluated for anti-inflammatory activity using indirect haemolytic and lipoxygenase inhibition assays and revealed good activity. The new complexes were characterized using spectroscopic methods in addition to elemental analysis.

The antimicrobial activity of crude methanolic extract of Ceratonia siliqua (Carob) extracted from pods was tested on 13 different references and food isolated bacterial pathogens (8 Gram positive and 5 Gram negative) and 8 different references and food isolated fungal pathogens. Antimicrobial activities of the pods of C. siliqua were comparable to those of reference antibiotics (Gentamicin or Amphotericin B). These encouraging results require further investigating in order to discover new antimicrobial agents. Key words: Ceratonia siliqua, antibacterial activity, antifungal activity, total phenolics, total flavonoids