The aim of this work is the synthesis of new derivatives of barbiturate of D-erythroascorbic acid. To obtain these derivatives, the 5,6-O-isopropylidene-L-ascorbic acid (4) was chosen, which was prepared from the reaction of L-ascorbic acid (3) as a starting material with dry acetone in the presence of hydrogen chloride. The esterification of hydroxyl groups at C-2 and C-3 positions with excess of benzoyl chloride in dry pyridine was obtained compound (5). Hydrolysis for compound (5) in acetic acid (65%) gave the compound (6). Oxidation of the product (6) with sodium periodate results an Aldehyde (7), which was reacted with dimethyl malonate in the presence of potassium hydroxide to give the malonate (8). The cyclocondensation reaction for compound (8) with urea, thiourea and guanidine hydrochloride gave the following compounds (9), (10) and (11) respectively. All these compounds were characterised by Thin Layer Chromatography (TLC) and FTIR spectra and some were characterised by (U.V-Vis) spectra, 1HNMR spectra and 13CNMR spectra.
In the present article, mixed ligand metal (II) complexes have been synthesized with Schiff base (1E, 5Z, 6E)-1,7 bis (4-hydroxy-3- methoxyphenyl)-5-(3-hydroxyphenyl) imino) hepta-1,6-dien-3-one derived from Curcumin and 3-aminophenol as primary ligand and L-dopa as a secondary ligand. The Schiff base act as bidentate and arrange to the metals through the azomethine (C=N) nitrogen and (C=O) oxygen atom. The mode of bonding of the Schiff base has been affirmed on the infrared by the UV-Visible, 1H, and 13C NMR spectroscopic techniques. The magnetic susceptibility and the UV-Vis data of the complexes propose octahedral geometry around the central metal ion. The information appears that the complexes have the structure of [L-M-(L-dopa)] system
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Gold nanoparticles (Au NPs) have been synthesized via reduction of sodium tetrachloroaurate dihydrate (NaAuCl4.2H2O) with 2-(2-methyl-5-amino -1H-imidazol-1-yl) ethanol (2-MAE) in presence and absence of ascorbic acid as reducing and stabilizing agents. The resulting Au NPs were characterized by UV–Vis spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD), FT-IR spectroscopy. The absorption spectra of gold nanoparticles solutions in the uv-visible and near IR regions were studied at different amine concentrations and pH media.
This work includes synthesis of new heterocyclic derivatives of 2-mercpto-3-phenyl-4(3H)-quinazolinone bearing 1, 2, 4-triazole and acetylenic amines moieties by using two ways. The first way includes reaction of 2-mercpto-3-phenyl-4(3H)-quinazolinone (1) with ethyl-2-bromopropanoate in methanol as solvent to gives ester derivative (2). Then, compound (2) was converted to (hydrazide, simecarbazid, phenylsimecarbazide and thiosimecarbazide) derivatives through its reactions with (hydrazine hydrate, simecarbazid, phenylsimecarbazide and thiosimecarbazide) respectively to give compounds (3-6). Finally, the cyclization of compounds (4-6) in alkaline media (4N-NaOH) gave the corresponding substituted triazole derivatives (7-9) respectively. W
... Show MoreNew membrane electrodes for determination of ciprofloxacin hydrochloride were prepared depending on ciprofloxacin hydrochloride - phosphotungstic acid (CFH-PT) as an active material and these electrodes were made with three plasticizers: Di-octylphenylphosphonate(DOPH), Di-butyl phosphate (DBP)Tri-n-butyl phosphate(TBP), in PVC matrix. One of the ciprofloxacin electrodes was gave Nernstian slope equal to 57.21 mV/ decade for DOPH membrane with concentration range from 1.5×10-5 to1.0×10-1 M, and detection limit equal to 1.5×10-6 M .Lifetime was 93 days. Non- Nernstian responses equal to 39.40 and 30.70 mV/ decade for membranes DBP, TBP, respectively. These electrodes were gave concentration range from 1.0× 10-5 to 1.0×10-2 and from 4.0
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Eleven new 2,6-di-tert-butyl-4-(5-aryl-1,3,4-oxadiazol-2-yl)phenols 5a–k were synthesized by reacting aryl hydrazides with 3,5-di-tert butyl 4-hydroxybenzoic acid in the presence of phosphorus oxychloride. The resulting compounds were characterized based on their IR, 1H-NMR, 13C-NMR, and HRMS data. 2,2-Diphenyl-1-picrylhydrazide (DPPH) and ferric reducing antioxidant power (FRAP) assays were used to test the antioxidant properties of the compounds. Compounds 5f and 5j exhibited significant free-radical scavenging ability in both assays.
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Complexes of 1-phenyl-3-(2(-5-(phenyl amino)-1,3,4- thiadiazole-2-yl)phenyl) thiourea have been prepared and characteized by elemental analysis, Ff-[R, and u.v./ visible spectra moreover, determination of metal content M%o by flame atomic absorption spectroscopy, molar conductance in DMSO solution and magnetic moments (peffl. The result showed that the ligand (L) was coordinated to Mn*2, Ni*2, Ct*2,2n*2,Cd*2, and Hg*2 ions through the nitrogen atoms and sulpher atoms. From the result obtained, rhe following general formula [MLClz] has been given for the prepared complexes with an octahedral geometry around the metal ions for all complexes. where M= Mn*2, Ni*2, cu*2, zn*z, cd*z, and Hg*2 l= l-phenyl-3-(2-(5-(phenyl amino)-1, 3,
... Show MoreAll new compounds synthesized by many reactions starting from a product the compounds [I]a,b from reaction of 3-phenylenediamine or 4-phenylenediamine with chloroacetyl chloride, then the compounds [I]a,b reacted with potassium thiocyanate to yield compounds [II]a,b. While the compounds[III]a,b yield from reacted the compounds [I]a,b with sodium azide then the compounds [III]a,b reacted 1,3-dipolar cycloaddition reaction with acrylic acid to give compounds [IV]a,b and the later compounds reacted with phenylene diamine to product benzimidazole compounds [V]a,b . In addition to synthesized acid chloride compounds [VI]a,b by reacted the compounds [IV]a,b with thionyl chloride .Finally reacted the compounds [VI]a,b with different aromatic amine
... Show MoreIn this work, lanthanium (III) complexes were synthesized using by Schiff base ligand (L) derived from benzaldehyde and o-aminoaniline with five amino acids (AA) from glycine (Gly), L-alanine (Ala), L-valine (Val), L-asparagine (Asp) and DL- phenylalanine (Phe). The Schiff base ligand has been characterized by elemental analysis, (MASS, FTIR, 1HNMR, 13CNMR, UV-VIS) electronic spectra. The structures of the new complexes have been described of analysis of elements, molar conductivity, (UV-Vis electronic, FTIR, mass) spectra also magnetic moment. The molar conductivity values of the complexes indicat this every of complexes are electrolytes and other analytical studies reveal octahedral geometry for La (III) ion. The Schiff base ligand, five
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