The work includes synthesis and characterization of some new heterocyclic compounds, as flow: The compound (3) (5-(4-chlorophenyl) -2-hydrazinyl-1,3,4-oxadiazole was synthesized by using two methods; the first method includes the direct reaction between hydrazine hydrate 80% and 5-(4-chlorophenyl)-2- (ethylthio) 1,3,4-oxadiazole (1), the second method involves converting 5-(4-chlorophenyl)-1,3,4-oxadiazol-2-amine (2) to diazonium salt then reducing this salt to compound (3) by stannous chloride. Compound (3) was used as starting material for synthesizing several fused heterocyclic compounds. The compound 6-(4-chlorophenyl)[1,2.4] triazolo [3,4,b][1,3,4] oxadiazole-3-(2H) thione (compound 4) was synthesized from the reaction of compound (3) with carbon disulfide in presence of potassium hydroxide. Compound 6-(4-chlorophenyl)-[1,2,4] triazolo [3,4-b][1,3,4] oxadiazole-3-amine (5) was synthesized from treatment of compound (3) with cyanogen bromide at room temperature in the presence of sodium hydrogen carbonate. Direct reaction between acetic acid and compound (3) in POCl3 affords 6-(4-chlorophenyl)-3-methyl-[1,2,4] triazolo [3,4,b][1,3,4] oxadiazole (compound 6). Five new fused rings derivatives (12-16) [6-(4-chlorophenyl)-3-(aryl)-[1,2,4] triazolo[3,4-b][1,3,4]oxadiazol] were synthesized by two steps. The first step was synthesized by corresponding Schiff bases (7-11) from reaction compound (3) with five aryl aldehyde. These Schiff bases were used as substrate to synthesize compounds (12-16) by treating these compounds with bromine in glacial acetic acid in dry sodium acetate.The synthesized compounds were characterized by FTIR,H-NMR,C-NMR and CHNS analysis.
In this study new derivatives of Schiff bases 5-8, 1, 3-oxazepine 9-16 and tetrazoles 17-19 have been synthesized from the new starting material 1 which has synthesized the reaction of one mole of dichloro acetic acid and two moles of thiophenol, the esters 2-3 were synthesized from the reaction of compound 1 with methanol or ethanol respectively in the presence of H2SO4 as catalyst then 2, 2-dithiophenylaceto Hydrazide 4 were synthesized from the reaction of 2 or 3 with hydrazine hydrate 80%, Schiff bases 5-8 were synthesized from the reaction of 4 with appropriate aldehyde or ketone. Treatment of Schiff bases with maleic and phathalic anhydride in dry benzene to give 1, 3-oxazepen derivatives 9-16 and with sodium azide in tetrahydrofuran
... Show MoreThe (E)-4-chloro-N-(2-(dimethylamino)ethyl)-5-((8-hydroxy quinolin-5-yl)diazenyl)-2-methoxybenzamide azo ligand (L) has been synthesized through the reaction of diazonium salt for 5-amino-4-chloro-N-(2-(dimethylamino) ethyl)-2-methoxybenzamide with 8-hydroxyquinoline and identified azo ligand (L) using spectroscopic studies (FTIR, UV-Vis, 1H and 13CNMR, mass), and micro-elemental analysis (C.H.N). Metal chelates of Co(II), Ni(II), Cu(II), as well as Zn(II) have been completed as well as characterized using mass spectra, flame atomic absorption, elemental analysis (C.H.N), infrared, UV-Vis spectroscopy, as well as conductivity, magnetic measurements. The metal-to-ligand ratio in all complexes, as determined by analytical data, was 1:2 and ex
... Show MoreOne of the most popular and legally recognized behavioral biometrics is the individual's signature, which is used for verification and identification in many different industries, including business, law, and finance. The purpose of the signature verification method is to distinguish genuine from forged signatures, a task complicated by cultural and personal variances. Analysis, comparison, and evaluation of handwriting features are performed in forensic handwriting analysis to establish whether or not the writing was produced by a known writer. In contrast to other languages, Arabic makes use of diacritics, ligatures, and overlaps that are unique to it. Due to the absence of dynamic information in the writing of Arabic signatures,
... Show Morein this work many amide polymers were prepared according to the modification reaction of polyacryloyl chloride or poluacrulic acid with different primary amines to mesuringninizing hormone were investgaited prior tq surgery in 10 postmenopaisal women with benign and 10 postmenopausal women with maliganant healthy
In this paper, Bayes estimators of the parameter of Maxwell distribution have been derived along with maximum likelihood estimator. The non-informative priors; Jeffreys and the extension of Jeffreys prior information has been considered under two different loss functions, the squared error loss function and the modified squared error loss function for comparison purpose. A simulation study has been developed in order to gain an insight into the performance on small, moderate and large samples. The performance of these estimators has been explored numerically under different conditions. The efficiency for the estimators was compared according to the mean square error MSE. The results of comparison by MSE show that the efficiency of B
... Show MoreIn this paper, Bayes estimators of the parameter of Maxwell distribution have been derived along with maximum likelihood estimator. The non-informative priors; Jeffreys and the extension of Jeffreys prior information has been considered under two different loss functions, the squared error loss function and the modified squared error loss function for comparison purpose. A simulation study has been developed in order to gain an insight into the performance on small, moderate and large samples. The performance of these estimators has been explored numerically under different conditions. The efficiency for the estimators was compared according to the mean square error MSE. The results of comparison by MSE show that the efficiency of Bayes est
... Show MoreIn this paper new methods were presented based on technique of differences which is the difference- based modified jackknifed generalized ridge regression estimator(DMJGR) and difference-based generalized jackknifed ridge regression estimator(DGJR), in estimating the parameters of linear part of the partially linear model. As for the nonlinear part represented by the nonparametric function, it was estimated using Nadaraya Watson smoother. The partially linear model was compared using these proposed methods with other estimators based on differencing technique through the MSE comparison criterion in simulation study.
Objectives: Two derivatives of cephalexin were synthesized by reaction with isatin-glycine Schiff base and bromoisatin-glycine Schiff base separately. Methods: Cephalexin was linked through the amine group to isatin glycine and bromoisatin glycine Schiff bases by amide bond formation. Results: These derivatives were characterized by FT-IR, H-NMR, elemental CHN analysis and then tested for their antimicrobial activity compared to cephalexin against gram-positive, gram-negative bacteria and Candida albicans fungi. Conclusion: The two compounds showed better activity against Staphylococcus aureus, compound 3b is more active against Escherichia coli, and compound 3a is more active against Klebsiella pneumonia.
A new two series of liquid crystalline Schiff bases containing thiazole moiety with different length of alkoxy spacer were synthesized, and the relation between the spacer length and the liquid crystalline behavior was investigated. The molecular structures of these compounds were performed by elemental analysis and FTIR, 1HNMR spectroscopy. The liquid crystalline properties were examined by hot stage optical polarizing microscopy (OPM) and differential scanning calorimetry (DSC). All compouns of the two series display liquid crystalline nematic mesophase. The liquid crystalline behaviour has been analyzed in terms of structural property relationship