Four novel Schiff bases SB1 to SB4 as new aromatic compound not hydrolysed under ordinary conditions were synthesized in this study by condensation reactions between2,4dinitrophenylhydrazine: firstly with 2,4,4`-trihydroxybenzophenone to give SB1, secondly with 4hydroxybenzophenone to give SB2, thirdly with 4-dimethylaminobenzaldhyde to give SB3 and fourthly with 4-aminobenzaldehyde to give SB4. The molecular structures of these aromatic Schiff bases obtained were identified and characterized based on melting points, elemental analysis(CHN), FT-IR and UV-Visible spectra. The electronic absorption spectra of Schiff bases obtained were studied in the solvents of ethanol, DMF, water, chloroform, carbon tetrachloride and cyclohexane. The recorded absorption bands in ethanol solvent were assigned to corresponding electronic transitions were discussed. The absorption bands at 291 to 411 nm obtained in electronic spectra of the synthesized new aromatic Schiff bases were assigned to (π→π*) transition which originates from substituted benzophenone or benzaldehyde rings and directed along of molecule in Schiff bases. These transitions are assumed to represent the intramolecular charge-transfer complexes bands in which the substituted two moieties of benzophenone and benzaldehyde rings are the charge donors and the substituted phenylhydrazine ring is the charge acceptor. Also, the effect of polar, non-polar solvents on the electronic transitions of charge-transfer bands have measured and discussed. The physical-spectroscopic parameters in molecular structural shapes of intra CT complexes molecules such as transition energies, molar extinction coefficients, molecular oscillate strength; transition molecular dipole moment and molecular resonance have been calculated and discussed.
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 MoreA new series of schiff base and aminothiadiazole derivatives of N- substituted phthalimide (I-VI) were synthesized. In this work, the intermediate 4-(1,3-dioxoisoindolin-2-yl)benzaldehyde compound (I), was formed by reaction of 4-amino benzaldehyde with phthalic anhydride in glacial acetic acid(GAA). A series of Schiff bases (IV-VI) was prepared by the reaction of benzidine with compound (I) in ethanol and presence of GAA as a catalyst to form compound (IV) which react with compound (I) and p-nitro benzyldehyde to give compound (V) and (VI) respectively. A new phthalimide thiosemi-carbazone derivative (ll) was prepared by reaction of compound (l) with thiosemi-carbazide HCl in the presence of equimolar amount of sodium acetate. Fina
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New compounds of amids [IV]a-e and Schiff bases [V]f-h derived from 2-amino-1,3,4-oxadiazoles [III] were synthesized and characterized by physical and spectraldata.2-Aamino-1,3,4-oxadiazoles was prepared by the action of bromine on acorresponding semicarbazide [II]( which was prepared by reaction of dialdehyde [I]with semicarbazide hydrochloride ) in the presence of sodium acetate , followed byan intramolecular cyclization . (PDF) Synthesis of New Amides and Schiff Bases derived From 2-Amino -1,3,4- Oxadiazole. Available from: https://www.researchgate.net/publication/326679206_Synthesis_of_New_Amides_and_Schiff_Bases_derived_From_2-Amino_-134-_Oxadiazole [accessed Nov 15 2023].
In our research novel schiff bases of imides moiety have been synthesized . Novel Schiff base derivatives of imides moiety have been synthesized by multistep reaction . First step involves prepare 2-amino -5-mercapto-1,3,4-thiadiazole (I) by the cyclization of thiosemicarbazide with carbon disulphide and anhydrous sodium carbonate in ethanol as a solvent . Then , compound (I) was reacted with phthalic anhydride in the presence of glacial acetic acid to give 2-(5-mercapto-1,3,4-thiadiazol-2-yl) isoindoline-1,3-dion (II).Compound (II)was heated with ethyl chloracetate in the presence of potassium carbonatproduced ethyl 2(5-(1,3-dioxoisoindoline -2-yl)-1,3,4-thiadiazole-2-yl thio) acetate (III).The reaction of compo
... Show MoreNew tetradentate Schiff base [H2L] namely [2,2׳ -(ethane-1,2- diylbis (azan-1-ylylidene) diacetic acid)] was prepared from condensation of ethylenediamine with glyoxylic acid in ethanol as a solvent in presence of drops of 48% HBr .The structure of ligand (H2L) was characterized by,F-IR, U.V-Vis.,1H-,13C-NMR, pectrophotometer,melting point and elemental microanalysis C.H.N. Metal complexes of the ligand (H2L) in general Molecular formula [M(L)(H2O)2], where M= Co(II), Ni(II), Cu(II), Mn(II) and Hg(II); L=(C6H8N2O4) were synthesized were characterized by, Atomic absorption, F-IR, U.V-Vis. spectra, molar conductivity and magnetic susceptibility.It was found that all the complexes showed octahedral geometries.And
... Show MoreA series of Schiff bases linked to phthalimidyl phenyl sulfonate moiety have been synthesized via multistep synthesis. The first step involved reaction of phthalic anhydride with aniline producing N-phenyl phthalamic acid which was subsequently dehydrated to the corresponding N-phenyl phthalimide via treatment with acetic anhydride and anhydrous sodium acetate. The synthesized imide was treated with chlorosulfonic acid in the third step producing 4-(N-phthalimidyl) phenyl sulfonyl chloride which was introduced in reaction with 4-hydroxy acetophenone in the fourth step producing 4-[4-(N-phthalimidyl) phenyl sulfonate] acetophenone and this in turn was introduced successfully in condensation reaction with various aromatic primary amines affor
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Objective: This study involved the synthesis of new Schiff bases and 1,3-oxazepine derivatives from the baclofen drug and study the anticancer activities. Methods: Baclofen was initially reacted with aromatic aldehydes to create Schiff base derivatives (Ia–Ib), which were then closed in the next step using anhydrous acids to form oxazepine derivatives (IIa–IId). Results: The title compounds were synthesized successfully and identified using FT-IR, 1H NMR, and 13C NMR spectroscopy. Additionally, compound (IIc)’s (3-(4-chloro-phenyl)-4-[2-(4nitro-phenyl)-4,7-dioxo-4,7-dihydro-[1,3] oxazepin-3-yl]butyric acid) anticancer activity was assessed using MTT assay against FTC-133 (thyroid cancer) compared with WRL-68 (normal cell line). Discus
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The new Schiff base, namely (2-Amino-phenylimino)-acetic acid (L) was prepared
from condensation of glyoxylic acid with o-phenylene diamine. The structure (L) was
characterized by, IR,
1
H,
13
C-NMR and CHN analysis. Metal complexes of the ligand (L)
were synthesized and their structures were characterized by Atomic absorption, IR and UV-Visible spectra, molar conductivity, magnetic moment and molar ratio determination (Co
+2
,
Cd
+2
) complexes. All complexes showed octahedral geometries.
The Schiff bases (1-10) were synthesized by the reaction of cefixime with aldehydes derivatives. The characterization of Schiff bases were carried out, by using spectroscopic techniques including IR, U.V – Vis, H1-NMR, EI-MS along with elemental analyses (C.H.N.).
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