In this present work, [4,4`-(biphenyl-4,4`-diylbis(azan-1-yl-1-ylidene))bis(methan-1-yl-1-ylidene)bis(2-methoxyphenl)(A1),4,4`-(biphenyl-4,4`-diylbis(azan-1-yl-1-ylidene))bis(methan-1-yl-1-ylidene)diphenol(A2),1,1`-(biphenyl-4,4`-diylbis(azan-1-yl-1-ylidene))bis(methan-1-yl-1-ylidene) dinaphthalen-2-ol (A3)]C.S was prepared in 3.5% NaCl. Corrosion prevention at (293-323) K has been studied by using electrochemical measurements. It shows that the utilized inhibitors are of mixed type based on the polarization curves. The results indicated that the inhibition efficiency changes were used with a change according to the functional groups on the benzene ring and through the electrochemical technique. Temperature increases with corrosion current (icorr) and potential (Ecorr) and decreases with CS covered by Schiff bases in the presence of inhibitors and temperatures decrease with efficiency (% PE) of CS in the absence and presence of inhibitors and using several techniques including infrared (FT-IR), scanning electron microscopy (SEM) and atomic force microscopy (AFM). Kinetic and thermodynamic activation parameters (Ea, A, ΔH*, S*, G*) were calculated for prepared vehicles. Then, the biological activity of the prepared compound (A1-A3) showed its efficiency with the use of Gram-positive and Gram-negative bacteria (Staphylococcus aureus, Staph.aure) and (Escherichia coli, E.coli), as well.
In this work, new Schiff bases of quinazolinone derivatives (Q1-Q5) were synthesized from methyl anthranilate. The synthesis involved three steps. In the first step, methyl anthranilate was reacted with isothiocyanatobenzene, producing the thiourea derivative K1. The second step entailed reacting K1 with hydrazine hydrate, synthesizing 3-amino-2-(phenylamino) quinazolin-4(3H)-one (K2). The third step involved reaction of K2 with various aromatic aldehydes, yielding the Schiff bases derivatives Q1-Q5. The chemical structures of these compounds were identified by FT-IR,1H NMR and 13C NMR spectroscopy. The newly synthesized derivatives (Q1-Q5) were subjected to rigorous evaluation to assess their efficacy as corrosion inhibitors for ca
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Condensation of 4-methoxybenzoyl hydrazine with 4- aminobenzoic acid in the presence of POCl3 gave the oxadiazole derivative [III] .This compound was demethylated with aluminium chloride to give series of 2- (4-hydroxy phenyl)-5-(4-amino phenyl)
1,3,4-oxadiazole [IV]. Series of Schiff s bases [V]n were synthesized by the condensation of compound [IV] with 4-n-alkoxy benzaldehyde in the presence of glacial acetic acid. Condensation of compounds [VI]n. with adipoyl chloride in dry pyridine leads to the formation of a new homologous series [VI]n. The structures of the synthesized compounds were confirmed by physical and spectral means The new compounds [VI]n have been screened for their antibacterial activities . The results
This work includes synthesis of new six membered heterocyclic rings with effective amino group using the reaction of benzylideneacetophenone (chalcone) (1) with thiourea or urea in alcoholic basic medium to form: 1,3-thiazen-2-amine (2), and 1,3-oxazin-2-amine (8) respectively. The diazotization reaction was carried out with sodium nitrite in presence of hydrochloric acid to form diazonium salts which suffered coupling reaction with naphthols and phenols in the presence of sodium hydroxide to form colored azo dyes (4-7, and 10-13). o-methylation reaction of compounds (7) and (10) yielded : 1,3-thiazin -2-yl-diazenyl (14), and 1,3-oxazin-2-yl-diazenyl (15) respectively.The new compounds were characterized using vario
... Show MoreThe new C-5 schiff bases derived from D-erythroascorbic acid contaning pyrimidine unit were synthesized by condensation of D-erythroascorbic acid with aromatic amine (containing pyrimidine unit)in dry benzene using glacial acetic acid as a catalyst. D-erythroascorbic acid was synthesized by four steps(Schem 1), while the aromatic amine which is containing oxopyrimidine or thiopyrimidine synthesized by the reaction of chalcone urea or thiourea in acid or basic medium, respectively . The structure of synthesized compounds have been characterized by their melting
... Show MoreObjective: Schiff’s and Mannich bases of isatins are an important group of heterocyclic compounds which are of great importance in medicinal chemistry as antimicrobial agents. In the vision of these facts, new bis-Schiff bases and Mannich bases of isatins were synthesized. Methods: Three different bis-Schiff bases (3a-c) have been synthesized by reacting isatin, 5-fluoroisatin and 5-methoxy isatin with thiophene-2- carboxaldehyde using hydrazine hydrate to link between the carbonyl compounds, and then these bis- Schiff bases were condensed with two different secondary amines (piperidine and morpholine) separately, and formaldehyde to form the Mannich bases (4a-c and 5a-f), respectively. Results: The structures of the newly synthesized com
... Show MoreA new series of ?-D-glucose as Schiff bases derivatives is synthesized and characterized with studying their bioactivity. Hydroxyl groups at C (1,2&5,6) sugar moiety are converted into acetal form through a reaction with dry acetone using phosphoric acid and anhydrous zinc chloride as catalysts producing 1,2:5,6-di-O-isopropyledine ?-D-glucofuranose(I). The five memberd ring acetal of C(5,6) is hydrolyzed with acetic acid (65%)and a reaction of the new product with sodium periodate is carried on to get an aldehyde moiety which is used to produce a new series of Schiff bases through reacting with different amino compounds such as 4-amino antipyrene . The suggested chemical structures of the prepared compounds are confirmed by using UV., FT
... Show MoreBy unusual method for separating two isomers of a substituted nitro-coumarin using a soxhlet extractor and in controlling temperature to get a selective nitration reaction, several new Schiff base coumarins were synthesized from nitro coumarins as starting material, which were reduced by Fe in glacial acetic acid to produce corresponding amino coumarin derivatives. Then the latter was reacted with different aromatic aldehydes to produce the desired Schiff bases derivatives. After characterization by Fourier transform infrared (FT-IR), Proton nuclear magnetic resonance (1HNMR) and Carbon-13 nuclear magnetic resonance (C-NMR), all these compounds were evaluated as potential Antimicrobial and Antioxidant Agents.
Two series of Schiff Bases and 2,3-disubstituted-1,3-thiazolidin-4-one derivatives were synthesized . Reaction of 2-mercaptobenzothiazole with α-chloro acetic acid gave compound[I]. Esterification of carboxylic moity of compound [I] , using absolute methanol in the presence of conc . H2SO4 yielded acorresebonding ester [II] , wich was condensation with hydrazine hydrate to give acid hydrazide [III] . The new Schiff bases [V]n were synthesized by reaction of acid hydrizide with dialdehyde [IV]n in the presence of glacial acetic acid . The thiazolidinone derivatives [VI]n have been obtained from the azomethines through the addition of thioglycolic acid . Their chemical structures have been confirmed by mel
... Show MoreIn this paper the new starting material 2-(5-chloro-1H-benzo[d]imidazole-2-yl) aniline (1) was synthesized by the condensation reaction of 4-chloro-o-phenylenediamine and anthranilic acid .The new Mannich base derivatives were synthesized using formaldehyde and different secondary amines to synthesize a new set of benzimidazole derivatives(2-5). Also, the new Schiff-base derivatives (6-10) were synthesized from the reaction of compound (1) with various aromatic aldehydes and the closure-ring was done successfully using mercapto acetic acid to get the new thiazolidine derivatives(11-12).These new compounds were characterized using some physical techniques like:FT-IR Spectra and 1HNMR Spectra.