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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 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.

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.

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 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.

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.

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.