A new heterocyclic Schiff bases ligand (HL) derived from condensation of 2-Amino-4-methylbenzothiazole with 4-Diethylaminosalicylaldehyde have been synthesized and characterized by (FTIR & UV.Vis) spectroscopies, (1H & 13C)NMR spectra, mass spectrum, elemental microanalysis (C,H,N,S). Metal complexes with Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) ions have been also synthesized and characterized by (FTIR & UV.Vis) spectroscopies, flame atomic absorption, molar conductivity measurements and magnetic susceptibility. These studies indicate that the mole ratio (L:M) is (2:1) for Co(II) complex and (1:1) for other complexes. The spectral results indicate that the ligand coordinates with metal ions as monobasic bidentate, via azomethine nitrogen and phenolic oxygen atoms. The study suggested octahedral geometry for Co(II), Ni(II) and Zn(II) complexes and square planar and tetrahedral geometries for Cu(II) and Cd(II) complexes, respectively. The enzyme activity of the ligand and its metal complexes with acetylcholine esterase1 (AChE) have also been studied. The study of enzyme activity indicates that the ligand and its metal complexes revealed different inhibition behaviors.
A series of nine new Schiff bases based on N-(4-acetophenyl)succinimide were synthesized via multistep synthesis. In the first step N-(4-acetophenyl)succinamic acid was prepared via reaction of succinic anhydride with 4-aminoacetophenone. The prepared amic acid was dehydrated in the second step producing N-(4-acetophenyl)succinimide. The prepared succinimide represents a modified methyl ketone bearing succinimde cycle and ready for introducing in condensation reaction thus in the third step the prepared imide was introduced in acid-catalyzed condensation reaction with a variety of primary aromatic amines affording the new target Schiff bases. The results of antibacterial screening of the newly synthesized Schiff bases indicated that they
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spectra and J>hysical methods,selected metals,which were Cu11
Zn 11
Mn11,Co11,Fe" and Hg11 were reacted with ligand to &
A series of new 1,8-naphthalimides linked to azetidinone, thiazolidinone or tetrazole moieties were synthesized. N-ester-1,8-naphthalimide (1) was obtained by direct imidation of 1,8-naphthalic anhydride with ethylglycinate. Compound (1) was treated with hydrazine hydrate in absolute ethanol to give N-acetohydrazide-1,8-naphthalimide (2). The hydrazine derivative (2) was used to obtain new Schiff bases (3-7). Three routes with different reagents were used for the cyclization of the prepared Schiff bases. Fifteen cyclic Schiff bases (8-22) with four- and five-membered rings were obtained.
The structures of the newly synthesized compounds were identified by their FTIR, 1H-NMR, 13C-NMR spectral data and some physical properties. Furtherm
The development of new cephalosporins with improved activity against resistant microbes, such as, MRSA (methicillin resistant Staph. aureus), P. aeruginosa, is of high potential. Chemical synthesis of two new series of thiadiazole linked to cysteine (series 1) and cephalosporins containing thiadiazole linked to cysteine through disulfide bond (series 2) were achieved. The chemical structures of the synthesized compounds were confirmed using spectral (FT-IR, 1H-NMR) and elemental microanalysis. The incorporation of privileged chemical moieties, such as, thiadiazole, Schiff base, cysteine and sulfonamide, has been found to have great contribution to the antimicrobial activities. Compounds of series 1 (1
... Show MoreThree ligands were prepared, spectroscopic method and elemental analysis verified their structures. The L1 and L2 ligands are flavylium salts while the third one L3 is a Flavon. The reactions between transition metal salts and the ligands have synthesized two groups of new metal complexes, one group contains L1, L3 coordinated with the metal ion. The other group contains L2, L3 and the metal. These complexes have been identified by available spectroscopic tools (UV-Visible and IR), the C.H.N results confirmed the proposed structures. The experimental data disclosed that the complexes were coordinated by 6the coordinate with mono-and bidentate ligands forming octahedral structure, in which L3 acts as monodentate and L1, L2 as bidentate ligan
... Show MoreCoumarin derivatives have shown different biological activities, such as antifungal, antibacterial antiinflammatory, and antioxidant activities, besides antibiotic resistance modulating effects, and anti-HIV, hepatoprotective, and antitumor effect. So, new coumarin derivatives (hydrazones and an amide) were synthesized through multisteps reactions. All the synthesized target compounds were characterized by FT-IR spectroscopy, 1HNMR analysis. The compounds then evaluated for their anti-bacterial activity by means of well-diffusion method against two gram-positive bacteria (Staphylococcus aureus, Streptococcus pneumoniae) and two gram-negative bacteria (E.coli and Pseudomonas aeruginosa). The highest activity was demonstr
... Show MoreThis work involves synthesis of amides containing isoxazoline unit starting with
chalcone; 4-[3-(3‾-nitrophenyl)-2-propene- 1-one]-aniline[I]. 4-Aminoacetophenone was
reacted with 3-nitrobenzaldehyde in basic medium giving chalcone [I] by claisen-schemidt
reaction. The chalcone [I] was reacted with hydroxylamine hydrochloride giving isoxazoline
[II] in NaOH basic medium. The amides with structural formula [III]a-h were prepared by the
reaction of amino compounds ; isoxazoline [II] with different acid chlorides in dry pyridine
and using DMF as a solvent at 4
0
C. All the synthesized compounds have been characterized
by melting points , FTIR and
1
HMNR (of compound [III]a) spectroscopy.
This research has presented a solution to the problem faced by alloys: the corrosion problem, by reducing corrosion and enhancing protection by using an inhibitor (Schiff base). The inhibitor (Schiff base) was synthesized by reacting of the substrates materials (4-dimethylaminobenzaldehyde and 4-aminoantipyrine). It was diagnosed by infrared technology IR, where the IR spectrum and through the visible beams proved that the Schiff base was well formed and with high purity. The corrosion behavior of carbon steel and stainless steel in a saline medium (artificial seawater 3.5%NaCl) before and after using the inhibitor at four temperatures: 20, 30, 40, and 50 C° was studied by using thr
... Show MoreThis research has presented a solution to the problem faced by alloys: the corrosion problem, by reducing corrosion and enhancing protection by using an inhibitor (Schiff base). The inhibitor (Schiff base) was synthesized by reacting of the substrates materials (4-dimethylaminobenzaldehyde and 4-aminoantipyrine). It was diagnosed by infrared technology IR, where the IR spectrum and through the visible beams proved that the Schiff base was well formed and with high purity. The corrosion behavior of carbon steel and stainless steel in a saline medium (artificial seawater 3.5%NaCl) before and after using the inhibitor at four temperatures: 20, 30, 40, and 50 C° was studied by using three electrodes potentiostat. The corrosion behavior was
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