The purpose of this research is to prepare new vanillic acid derivatives with 1,2,4-triazole-3-thiol heterocyclic ring and evaluate their antimicrobial activity in a preliminary assessment. A multistep synthesis was established for the preparation of new vanillic acid-triazole conjugates. The intermediate of 4-(4-amino-5-mercapto-4H-1,2,4-triazol-3-yl)-2-methoxyphenol (4) reacts with different heterocyclic aldehydes (thiophene-2-carboxaldehyde, pyrrole-2-carboxaldehyde, thiophene-3-carboxaldehyde, and furfural ) in ethanol containing few drops of acetic acid yielded the corresponding 4-(4-(substituted amino)-5-mercapto-4H-1,2,4-1triazol-3-yl)-2-methoxy phenol derivatives (5-8). These compounds were characterized spectroscopically by FT-1IR and 1H-1NMR. These imine derivatives (5-8) were tested for their antimicrobial activity and compared with three different standard references (amoxicillin, ciprofloxacin, and fluconazole). Overall, compounds 6 and 8 exhibited varying degrees of inhibitory effects on the growth of the examined bacterial species and fungus. The most active one is compound 6 having pyrrole ring imine derivative showed potent activity against C. 1albicans and moderate activity against all tested bacteria compared to other derivatives but no activity toward P. 1aeruginosa and P. 1mirabilis.
New heterocyclic compounds derived from 2-Morpholino-1,8-naphthyridine-4-carboxylic acid such as oxadiazolo, thiadiazolo – thione and triazolo-thione have been prepared and characterized on the basis of IR and 1H NMR spectra data. The hydrizide compound was utilized as a starting material for preparing of these compounds. The second part of this study involves the biological studies of some of these naphthyridine derivatives by using three different kinds of bacteria namely: Staphylococcus aureus, Pseudomonas aeruglnosa and Escherichia coli. The data indicated that some of these compounds have a good activity against the tested bacteria in comparison to antibiotics.
Schiff bases of Ceftizoxime sodium were synthesized in an attempt to improve the antimicrobial spectrum of Ceftizoxime. Aminothiazole ring of Ceftizoxime is linked directly through an imino group to different aromatic aldehydes reacted by nucleophilic addition using trimethylamine (TEA), as a catalyst and refluxed in methanol. The antimicrobial activity was evaluated for such Schiff bases using disc diffusion method. Molecular docking was conducted on certain penicillin-binding proteins (PBPs) and carboxypeptidases using 1- click docking software. Schiff bases of Ceftizoxime were prepared with reasonable yields and their chemical structures were confirmed by spectral analysis (FTIR, 1H-NMR) and elemental microanalysis (CHNS). The antibacter
... Show MoreIsatin (1H-indole-2, 3-dione) and its analogs are an important class of heterocyclic compounds. N-benzyl isatins and Schiff bases of isatin analogs have been reported to demonstrate a variety of biological activities. This work illustrates the synthesis of new N-benzylisatin Schiff bases and studies their biological activity. Firstly, Isatin and its analogs; 5-methoxyisatin, 5-fluoroisatin reacted with benzyl iodide to obtain N-benzylated derivatives of isatins 2 (ac). Secondly, these compounds were reacted with different amines (sulphanilamide and 4-methyl sulphonyl aniline) separately, to obtain Schiff bases compounds 3 (ac) and 4 (ac), respectively. The synthesized compounds were characterized by using FT-IR and 1HNMR spectroscopy. The s
... Show MoreNew Schiff bases derivatives [IV]a-e is prepared via condensation of Derythroascorbic acid with p-substituted aldehydes in dry benzene. To obtain these derivatives, the 5,6-O-isopropylidene-L-ascorbic acid[I] was chosen as starting material, compound prepared from the reaction of L-ascorbic acid as starting material. Compound[I] was prepared from the reaction of L-ascorbic acid with dry acetone in the presence of hydrogen chloride. The esterification of hydroxyl groups at C-2 and C-3 positions with excess ofethyl α –chloroacetate in the presence of sodium acetate produce acorresebonding ester [II] , which was condensed with hydrazine hydrate to give new hydrazide [III] . The new Schiff bases [IV]a-e were synthesized by reaction of acid h
... Show MoreIn this work, a series of new maleimides linked to substituted benzothiazole moiety were synthesized. Synthesis of these new cyclic imides were performed via three steps, the first one involved preparation of a series of 2-aminobenzothiazole substituted with different substituents via reaction of different primary aromatic amines with ammonium thiocyanate and bromine in glacial acetic acid. The prepared 2- amino benzothiozoles were introduced in the second step in reaction with maleic anhydride producing a series of N-(substituted benzothiazole-2-yl) maleamic acids.The resulted maleamic acids were dehydrated in the third step via treatment with acetic anhydride and anhydrous sodium acetate to afford a series of the desirable N-(substitu
... Show MoreIn this research , phthallic anhydride ring is opened with 4-methyl aniline and acetone as a solvent to results the compound [I] that reacted with dimethyl sulphate and anhydrous sodium carbonate formation to phathalate ester [II], while the acid hydrazide compound [III], was obtained from mixed the compound [II]with hydrazine hydrate, Synthesis four type of shiff bases[IV]a-d was synthesized from the reaction of acid hydrazide [III] with aromatic aldehyde or ketone , when reacted Shiff bases with phthalic anhydride or naphthalicanhydride,I get eight derivatives of oxazepine [V]a-d , [VI]a-d. The bacterial activity of the new compounds studied by four species of bacteria: Esherichia Coli, Enterobactecloacae (Gram negative) and staphylococcu
... Show MoreMetal complexes of Mn(II), Co(II), Ni(II), Cu(II), Cd(II), Zn(II), Hg(II), Pd(II), and Pt(II) with Schiff base ligand (LH) derived from 2,5-dichloroaniline and 2-hydroxy-5-metheylbenzalaldehyde were synthesized and characterized using a variety of spectrophotometric techniques The findings of the spectroscopic analysis indicated that (LH) behaved as a binary coordinating agent to the metal ion by the N and O atoms, and the geometry shape of the complexes was octahedral, with the exception of the Pd and Pt complexes, which had a square planar geometry. Using the DPPH radical scavenging method, we investigated the antimicrobial activity of the compound against Staphylococcus aureus and Escherichia coli, as well as the antifungal activity of t
... Show MoreNew series of 2-mecapto benzoxazole derivatives (1-20) incorporated into fused to different nitrogen and suphur containing heterocyclic were prepared from 2-meracpto benzoxazole, when treated with hydrazine hydrate to afford 2-hydrazino benzoxazol (1). Compound (1) converted to a variety of pyridazinone andphthalazinone derivatives (2-4) by reaction with different carboxylic anhydride. Also, reaction of (1) with phenyl isothiocyanate and ethyl chloro acetate afforded 3-phenyl-1,3-thiazolidin-2,4-dione-2-(benzoxazole-2-yl-hydrazone) (6). Azomethines (7-10) were prepared through reaction of (1) with aromatic aldehyde, then (7, 8) converted to thaizolidinone derivatives (11, 12). Treatment of (1) with active methylene compounds afforded deriva
... Show MoreIn this work 2-hydrazino pyrimidine (1) was prepared from 2-mercapto pyrimidine with hydrazine hydrate. Treatment of (1) with active methylene compounds gave 2-(3,5-dimethyl -1 H – Pyrazole-1-yl) pyrimidine , whereas the reaction of (1) with carboxylic anhydride namely maleic anhydride or 1,2,3,6-tetra hydro phthalic anhydride yielded 1-Pyrimidine-2-yl-1,2-dihydro pyridazine-3,6-dione (3) and 2 – Pyrimidin -2-yl -2,3,4 a ,5,8 a – hexahydro phthalazine 1,4 – dione (4) . Reaction of (1) with phenyl isothiocyanate and ethyl chloro acetate afforded 3-Phenyl-1,3-thiazolidine-2,4-dione-2( pyrimidine -2- yl hydrazone (6) Azomethine (7-10) were prepared through condensation of (1) with aromatic aldehydes or ketones, then comp
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