This study has three parts, the first one is the synthesis of a novel Schiff bases by the condensation of guanine or 9-[{2-hydroxyethoxy}methyl]-9H-guanine with variety aldehydes to yield four different bases as follows: (E)-2-((4-nitrobenzylidene)amino)-1,9-dihydro-6H-purin-6-one (S1), (E)-2-((4-methoxybenzylidene)amino)-1,9-dihydro-6H-purin-6-one (S2), (E)-2-((2-hydroxybenzylidene) amino)-9-((2-hydroxy ethoxy)methyl)-1,9-dihydro-6H-purin-6-one (S3), and (E)-2-(((9-((2-hydroxy ethoxy)methyl)-6-oxo-6,9-dihydro-1H-purin-2-yl)imino)methyl)benzoic acid (S4). Then, spectroscopic analyses such as Elemental Analysis, UV/VIS, Mass spectra, FTIR, 1H,13C-NMR were made to recognize these bases. In the second part, the ability of synthesized bases to undergo a charge transfer reaction was examined in an ethanolic solution at 28℃ with Iodine (I2) and 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) acceptors. The nonbonding interactions were studied using Benesi–Hildebrand method to estimate the stability parameters for all formed charge transfer complexes. The results of CT-energies and Gibbs free energies (ΔG˚) confirmed the stability of these complexes, and all complexes follow the Benesi–Hildebrand equation. The results showed that the DDQ-complexes have an affinity constant ranging from (916.6–24,400) mol−1.L higher than the affinity constant of I2-complexes which ranges from (428.5–7000) mol−1.L. Moreover, the KCT of S2 > S1 and KCT of S4 > S3 were as follows [1222.2 for S1-I2, 4333.3 for S1-DDQ, 2812.5 for S2-I2, 4800 for S2-DDQ] and [3809.5 for S3-I2, 12,200 for S3-DDQ, 7000 for S4-I2, 24,400 for S4-DDQ] due to the specific properties of each compound. The direct energy gap (Egdir) of each complex was also obtained by applying Tauc's method. Iodine complexes with S1, S2, S3, S4, as well as S1-DDQ displayed energy gaps equal to (5.14, 5.11, 4.61, 4.51, and 3.90) eV, respectively, and are likely to act as insulators. In contrast, the DDQ complexes of (S2/S3/S4) bases exhibited Egdir values at (2.85–2.24) electron volts which makes them suitable for semiconductor material usage. Finally, the third part of this work included a theoretical study using DFT/B3LYP/3-21G method to illustrate and prove the experimental findings, which were consistent with the theoretical results.
A series of benzohydrazide derivatives attached to coumarin moiety at position 6 and 7 have been synthesized. The reaction of coumarin derivatives (coumarin I and II) with p-nitrophenyl hydrazine yield Schiff bases (compound1a and IIa).These Schiff bases were refluxed with benzoyl chloride to give benzohydrazide derivatives of coumarin substituted at its 6 or 7 nucleus position (Ia1 and IIa1).The reaction and the purity of the products were checked by thin layer chromatography (TLC). The structures of the final compounds and their intermediates were confirmed by their melting points, infra red spectroscopy, and elemental microanalysis(CHN).
Compounds (Ia1 and IIa1) were evaluated for&n
... Show MoreIn this work, novel compounds of hydrazones derived from (2,4-dinitrophenyl) hydrazine were synthesized. Benzamides derivatives and sulfonamides derivatives were prepared from p-amino benzaldehyde. Then these compounds were condensed with (2,4-dinitrophenyl) hydrazine through Imine bond formation to give hydrazones compounds. The compounds were characterized using FT-IR (IR Affinity-1) spectrometer, and 1HNMR analyses. The majority of the compounds have a moderate antimicrobial activity against “Gram-positive bacteria staphylococcus Aureus, and staphylococcus epidermidis, Gram-negative bacteria Escherichia coli, and Klebsiella pneumoniae, and fungi species Candida albicans” using concentrations of 250 µg\ml.
A new series of metal ions complexes of VO(II), Cr(III), Mn(II), Zn(II), Cd(II) and Ce(III) have been synthesized from the Schiff bases (4-chlorobenzylidene)-urea amine (L1) and (4-bromobenzylidene)-urea amine (L2). Structural features were obtained from their elemental microanalyses, magnetic susceptibility, molar conductance, FT-IR, UV–Vis, LC-Mass and 1HNMR spectral studies. The UV–Vis, magnetic susceptibility and molar conductance data of the complexes suggest a tetrahedral geometry around the central metal ion except, VOII complexes that has square pyramidal geometry, but CrIII and CeIII octahedral geometry. The biological activity for the ligand (L1) and its Vanadium and Cadmium complexes were studied. Structural geometries of com
... Show MoreOxazine and quinazoline has a very important in organic chemistry especially in hetero cyclic fields. this research consist the preparation of 4H,4'H-2,2'-bibenzo[d][1,3]oxazine-4,4'-dione compound (1) from di acid chloride with 2-aminobenzoic acid in pyridine as solvent to give compound (2) 3,3'-diamino-2,2'- biquinazoline-4,4'(3H,3'H)-dione .compound 2 include free amino group .this compound was reacted with maleic and phthalic anhydride for synthesized of cyclic imide compounds (3,4).another reaction for compound 2 with some substituted aromatic aldehyde for prepared of some novel Schiff bases (5-9) contains quinazoline ring. compound 1 was treated with sulfathiazole and sulfadiazine for synthesized of sulfa compounds contains sulf
... Show MoreIn this research the specific activity of natural radionuclides 226Ra, 232Th and 40K were determined by sodium iodide enhanced by thallium NaI(TI) detector and assessed the annual effective dose in Dielac 1 and 2 and Nactalia 1 and 2 for children of less than 1 year which are available in Baghdad markets. The specific activity of 40K has the greater value in all the types which is in the range of allowed levels globally that suggested by UNSCEAR. The mean value of annual effective doses were 2.92, 4.005 and 1.6325 mSv/y for 226Ra, 232Th and 40K respectively.
الهدف من الدراسه تحضير فئه جديده من بوليمرات السليكون P1-P4 والتي تمت على اساس استحدام ثنائي مثيل ثنائي كلورو سيلان((DCDMS مع بعض المركبات العضويه التي تحتوي مجاميع الهيدروكسيل الطرفيه والتي حضرت لاول مره M1-M4، بأستخدم البلمره التكثيفيه .كما تم تحضير متراكباتها النانويهP′1-P′4 بوجود جسيمات الفضه النانويه (Ag-NPs) باستخدام طريقة صب المحاليل. شخصت جميع التراكيب للمونمرات والبوليمرات المحضره باستخدام مطيافية
... Show MoreThe present work establishes and validates HILIC strategies simple, accurate, exact and precise in pure form and inpharmaceutical dosage for separating and determining theophylline. These methods are developed on HILIC theophyllineseparation in columns ZIC2 and ZIC3. The eluent was prepared by mixing buffer (20% sodium acetate-40 mM, pH 5.5), 80%acetonitrile. The flow rate is 0.8 mL/min, with gradient elution and UV detection at 270 nm. In the ZIC2 and ZIC3 columns oftheophylline determining, the concentration range was 0.01-4μg.ml-1. The lower limit of detection and quantification fortheophylline were determined as 0.130, 0.190 μg.ml-1 and accuracy were 99.70%, 99.58% on ZIC2 and ZIC3, respectively. TheHILIC methods developed and validat
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