Free radicals are reactive compounds, their excessive production is considered to be an important cause of oxidative damage in biomolecules causing degenerative diseases. Polyphenols are one of the most important groups of secondary metabolites of plants, which have an antioxidant activity depending on their properties as hydrogen donors. Echinops polyceras Boiss. (Asteraceae) is one of Echinops genus species that spread in Syria, Lebanon, and Palestine. Phytochemicals found in this species leaves have been extracted with gradient polarity solvents, and primary screening of the secondary metabolites was established. The phenolic compounds and flavonoids contents were determined. The free radicals scavenging activity was evaluated for all extracts with DPPH• in a 96-well microplate. The specificity study indicates that ascorbic acid was absent, and reducing sugars were exist in the aqueous extract. The identification tests showed the presence of polyphenols like flavonoids and coumarins. The methanolic extract of the E. polyceras leaves was the most effective scavengers of free radicals (90.22% in 30 min) with phenolic compounds content 682.5 mg GAE/g of dried extract (DE) and flavonoids content 194.5 mg QE/ g DE. The chloroform extract was the least effective as free radical scavenging (60% in 30 min) as the phenolic compounds content was 278.5 mg GAE/g DE and flavonoids content 94 mg QE/ g DE. In conclusion, the phenolic compounds and flavonoids from Echinops polyceras Boiss. are effective in free radicals scavenging and protecting from diseases caused by oxidative stress.
In this work a series of fourteen new compounds were synthesized. Compound [1] was formed from the reaction of 2-aminobenzothiazole and p-bromophenacyl bromide. Aldehyde group [2] was obtained from the reaction of compound [1] with pocl3 in presence of DMF and CHCl3 .After that shiff bases have been synthesized from the reaction of compound [2] with different aromatic amine to give new shiff bases [3- 5]. These new shiff bases have been reduced to their corresponding amine [6-8] by means of sodium borohydride. Then reaction of shiff bases [3-5] with phenyl isocyanate gives 3-cyclic lactam derivatives [9-11]. 3-cyclic Oxazepine derivatives [12-14] were obtained by reaction of shiff bases [3-5] with succinic anhydride. These new formed co
... Show MoreIn this research investigation, a total of eighteen diverse tetra- and penta-lateral cyclic compounds were synthesized. These included 1,3,4-thiadiazole, thiazolidin-4-one (via an alternative method), 1,2,4-triazole, carbothioamide, thiazole-4-one, azetidin-2-one, and oxazole. The synthesis procedure entailed a sequence of reactions. The thiazolidine-4-one 1 was obtained by reaction p-aminobenzoic acid with thiosemicarbazide, followed by treatment with p-tolualdehyde to produce Schiff base 2. Reaction Schiff base 2 with mercaptoacetic acid in dry benzene was carried out to produce thiazolidine-4-one 3. In another synthesis pathway, the esterification of p-nitro benzoic acid with ethanol in the presence of sulfuric acid was
... Show MoreUsing an electrochemical polymerization technique at room temperature, poly nicotine amide (PNA) was produced from the monomer nicotine amide (NA) in aqueous solution. The structure of polymer layer generated on the stainless steel surface (316 L) (working electrode) is investigated by Fourier Transmission Infrared Region (FT-IR). The anti-corrosion activity of polymer coating on the stainless steel (SS 316 L) is investigated by electrochemical polarization in 0.20M solution of HCl at 293-323K. The graphene -modified polymer film-coated SS had greater protection efficiency (PE percent) when compared to Nano ZnO -modified polymer film-coated SS. For the corrosion process of SS 316 L, kinetic and thermo-dynamic parameters of activatio
... Show MoreA series of new heterocyclic aromatic derivatives compounds were synthesized by reacted of Bis-methylene-di-(2-aminobenzoyl chloride) with different chloride moieties such as piperidine-1-sulfonylchloride, Pryidine-3-sulfonylchloride, 4,4and#39;-(diazene-1,2-diyl)dibenzoyl-chloride and chloramphenicol respectively, to afforded a derivatives compound containing primary amine group [A-A4]. These derivative compounds [A-A4] were reacted with polyethanol using cold-warm esterification to synthesize of new graft polymers [B1-B4]. The structures of products were conforming by FT-IR and 1H-NMR spectroscopy. XRD-Diffraction of grafted polymer showed compound [B1 and B3] were crystal and semi-crystal respectively. As well as, derivatives
... Show MoreObjective: The antimicrobial efficacy of three disinfection solutions: 5.25% sodium hypochlorite (NaOCl), 2% chlorhexidine (CHX) and Listerine mouthwash were investigated as routine chair-side gutta-percha (GP) disinfection reagents. Design: four groups of gutta percha points were contaminated with E. faecalis bacteria then disinfected by immersion in different solutions (5.25% sodium hypochlorite, 2% chlorhexidine gluconate, Listerine mouth wash and distilled water as control) after 1 and 7 days culturing periods. The antibacterial efficacy of these disinfection solutions was evaluated by using colonies per units (CPU) Methods: Forty GP cones (F3 Dentsply) were sterilized with ethylene oxide gas before immersed contamination within broth m
... Show MoreNearly, in the middle of 1970s the split-brain theory became the only theory that explains human creativity used in all fine art and art education schools. In fact, this theory- which appeared for first time in the middle of 1940s – faced many radical changes including its concepts and structures, and these changes affected both teaching art and art criticism. To update people awareness within art field of study, this paper reviews the split-brain theory and its relationship with teaching art from its appearance to its decay in 2013 and after.
A new methodology was applied to the synthesis of new imidazolones and oxyazepine derivatives containing imidazo thiazole fused rings. Starting with 5-(4-bromo phenyl) imidazo (2, 1-b) thiazole, which was synthesized using the standard procedure, the Carbaldehyed group was introduced at position 6 of 5-(4-bromo phenyl) imidazo (2, 1-b) thiazole. Then, this 6-carbaldehyed derivative was condensed with different substituted aromatic amines to afford new Schiff bases. The latter were cyclized into new oxazepine and imidazolone derivatives by using phthalic anhydride and glycine, respectively. These new derivatives were characterized by using FT-IR, 1HHNMR, and 13CNMR spectra, as well as examined (evaluated) for anti-bacterial and anti-fungal a
... Show MoreNew Schiff bases derivatives [IV]a-e is prepared via condensation of Derythroascorbic acid with p-substituted aldehydes in dry benzene. To obtain these derivatives, the 5,6-O-isopropylidene-L-ascorbic acid[I] was chosen as starting material, compound prepared from the reaction of L-ascorbic acid as starting material. Compound[I] was prepared from the reaction of L-ascorbic acid with dry acetone in the presence of hydrogen chloride. The esterification of hydroxyl groups at C-2 and C-3 positions with excess ofethyl α –chloroacetate in the presence of sodium acetate produce acorresebonding ester [II] , which was condensed with hydrazine hydrate to give new hydrazide [III] . The new Schiff bases [IV]a-e were synthesized by reaction of acid h
... Show MoreThe aldol condensation of 2-acetylnaphthalene with 9-anthracene carboxaldehyde afforded α, β-unsaturated keton (1) . New heterocyclic compounds containing: cyclohexenone[2], indazole[3], pyrimidinethion [4], thiazolo fused pyrimidine[5], isoxazoline[6], substituted pyrazoline[7]a-d and pyrimidinone[8] rings system were synthesized from α, β-unsaturated keton[1]. Cyclization of [1] with ethylacetoacetate gave the mentioned heterocycle cyclohexanone [2]. The cyclo condensation of [2] with hydrazine gave the new indazole derivative [3]. furthermore, the reation of [1]with thiourea gives thiopyrmidine derivative [4]. The cyclo condensation of [4] with chloroacetic acid gave the fused rings [5]. Then reacted compound[1] with hydroxy
... Show MoreThe study involved the synthesis of new complexes with tetradentate ligand (LH). The general formula of complexes was [M(LH)(H2O)2] with M of Ni2+, Co2+, Cu2+, and Zn+. The ligand was synthesized by treating the 2-hydroxybenzohydrazide with salicylaldehyde. The structural characteristics of ligands and complexes were analyzed using various techniques, including elemental analyses, magnetic susceptibility, molar conductivity, infrared, ultraviolet absorption, mass, and NMR spectroscopy studies. The physical measurements indicated that the prepared complexes are non-electrolyte and showed that the ligand is tetradentate when coordinated with metal ions through the nitrogen of azomethine (–C=N–), two oxygen atoms of O–H phenolic,
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