This work includes synthesis of some new derivatives of Schiff bases as intermediate compounds. Through the reaction 1,4- phen ylene diamine with different aromatic aldehydes substituted by many different groups in acidic medium and absolute ethanol as a solvent to obtain the Schiff bases (1a-5a). These compounds are reacted with substituted aromatic carboxylic acids and anhydride to give three types of heterocyclic compounds. The first line includes direct reaction with maleic anhydride under certain conditions to give new derivatives of oxazpine(6b-10b). The second line includes reaction of compounds (1a-5a) with 2-mercapto benzoic acid in the presence of triethyl amine as a catalyst and dry benzene as a solvent to give new derivatives of thiazinone(11c-15c). While the third line involved reaction the Schiff bases (1a-5a) with anthranilic acid in dioxane as solvent to give new derivatives of hydroquinazoline (16d-20d). The structures of these new synthesized compounds were identified by spectral methods their [FTIR, 1HNMR, 13C-NMR] and measurements of some physical properties and some specific reactions. Furthermore the effects of synthesized compounds on some strains of bacteria were studied.
The Chemistry of heterocyclic sulphur and nitrogen containing compounds have a great role in the field of scientific studies, The 2-amino 5-mercapto-1,3,4-thiadiazole ring for instance, has gained more importance in recent years because they are considered as potent biologically active nucleus. In this study disulfide derivative can be obtained by oxidation with hydrogen peroxide of thiol group of the heterocyclic 2-amino 5-mercapto-1,3,4-thiadiazole ring to obtain compound (3) with expected antibacterial activity. In order to use it as a diazo component to prepare some new bis azo compounds as possible antibacterial agents, the reaction of two primary amino groups on both sides of disulfide dimer with sodium nitr
... Show MoreFive species of Lactic acid bacteriawere isolated from raw milk, yoghurt, vegetables and pickles, Lactobacillus plantarum, Lactobacillus acidophilus, Lactobacillus brevis, Lactobacillus casei and Lactobacillus bulgaricus isolates were identified by 16S rRNA gene. Evaluate of antimicrobial activity against all the bacterial strains Staphylococcus aureus, Salmonella spp., Pseudomonas fluorescens, Escherichia coli, Bacillus cereus and Bacillus subtilis. It showed that bacteriocin of Lactic acid bacteriamore effective than supernatant of lactic acid bacteria, the results showed that isolatemost efficient isolate belonging to Lactobacillus brevis, the diameter of the inhibition of the bacteriocin of Lactobacillus brevis were 27.7, 26.3 and 25.1
... Show MoreCondensation of 1,2- dibromo ethane with para hydroxy benzoic acid gave 1,2-Ethane-bis- 4-oxybenzoic [1]. This Compound was converted with the thionyl chloride to give 1,2-Ethane-bis- 4-oxybenzoyl chloride [2]. Reaction of compound [2] with thiosemicarbizades gave 1,2-Ethanebis[4-oxybenzoyl-thiosemicarbazide] [3] and opteined 1,2-Ethane-bis[3-mercapto-5-phenoxy- 1,2,4-triazole] [4] from treatment compound [3] with NaOH (4%) .The new compounds 1,2- Ethane-bis[3-(substituted thioacyl)-4-(substituted acyl)-5 phenoxy-1,2,4-triazole] [5a-d] and 1,2- Ethane-bis[3-(substituted alkylthio)-5 phenoxy-1,2,4-trizole] [5e-f] derived from compound [4] were synthesized and characterized by physical and spectral data. All the compounds [4], [5a-d] and [5e-
... Show MoreThis research, involved a series of some new compounds containing different hetero cyclic new pentagonal and hexagonal rings, through the reaction of 2-mercapto-3-phenyl-4(3H)quinazolinone (1) with chloroacetylchloride in the presence of potassium hydroxide, and dry dimethylformamide (DMF) as a solvent to obtain the intermediate compound (2). This compound is reacted with different reagents to give four routes, the first route include direct reaction with substituted-2-aminobenzothiazole under certain conditions to give new compounds (3-9). The second route involved condensation compound (2) with 5-substituted-2-amino-1,3,4-oxadiazole in the presence of potassium carbonate anhydrous to give new compounds (10-13).while the third route inv
... Show MoreThis research, involved a series of some new compounds containing different hetero cyclic new pentagonal and hexagonal rings, through the reaction of 2-mercapto-3-phenyl-4(3H)quinazolinone (1) with chloroacetylchloride in the presence of potassium hydroxide, and dry dimethylformamide (DMF) as a solvent to obtain the intermediate compound (2). This compound is reacted with different reagents to give four routes, the first route include direct reaction with substituted-2-aminobenzothiazole under certain conditions to give new compounds (3-9). The second route involved condensation compound (2) with 5-substituted-2-amino-1,3,4-oxadiazole in the presence of potassium carbonate anhydrous to give new compounds (10-13).while the third route inv
... Show MoreIn this research, 5- membered heterocyclic compounds as oxazolidine-5-one J1-J5 derivatives were prepared using primary aromatic amine, aromatic carbonyl compounds and chloroacetic acid. By combining primary aromatic amines and aromatic carbonyl compounds, Schiff's bases were synthesized. Schiff bases are used with the chloroacetic acid compound to prepare oxazolidine-5-one J1-J5 derivatives. The compounds J1-J5 were described using NMR spectroscopy and FT-IR. .The biological efficacy was evaluated according to maximum inhibitory concentrations (MICs) toward Staphyloccoccus aureus and Esherichia coli. The best MIC was 210 μg ml-1 for J4 against the two pathogenic bacteria, while J1, J4, and J1 did not show any inhibitory effect against all
... Show MoreIn this research investigation, a total of eighteen diverse tetra- and penta-lateral cyclic compounds were synthesized. These included 1,3,4-thiadiazole, thiazolidin-4-one (via an alternative method), 1,2,4-triazole, carbothioamide, thiazole-4-one, azetidin-2-one, and oxazole. The synthesis procedure entailed a sequence of reactions. The thiazolidine-4-one 1 was obtained by reaction p-aminobenzoic acid with thiosemicarbazide, followed by treatment with p-tolualdehyde to produce Schiff base 2. Reaction Schiff base 2 with mercaptoacetic acid in dry benzene was carried out to produce thiazolidine-4-one 3. In another synthesis pathway, the esterification of p-nitro benzoic acid with ethanol in the presence of sulfuric acid was
... Show MoreNew 2-Mercaptobenzimidazole derivatives were synthesized. 4,5-disubsitituted 1,2,4-Triazole compounds 1b-2c were synthesized from 2-(benzylthio) benzimidazole compound a, which was then reacted with (NaH) in dioxane at a temperature of (0-5 C°) to produce the salt of compound a. Then the salt was reacted with ethyl chloro acetate to yield Ethyl 2-(benzylthio) benzimidazole acetate compound b. Compound b was converted to triazole derivatives by two pathways. The first pathway was reacting compound b with semicarbazide, thiosemicarbazide and phenylsemicarbazide in DMSO as a solvent to gain compounds 1b-3b, which were then
... Show MoreNew hydrazide compounds (A2) and (A9) were prepared from their corresponding esters (A1, A8) .These esters were also prepared from their precursors 5-ethoxy carbonyl-(4methoxyphenyl)-6-methyl-1,2,3,4-tetrahydropyrimidine-2-thione (A1) via multicomponent reaction type and from hippuric acid respectively. The hydrazide compounds were then allowed to react with some aldehydes forming the corresponding hydrazones (A3-7) and (A1014). The synthesized compounds were characterized by IR, 1H-NMR, 13C-NMR, and Mass spectroscopies and well discussed. .
This work includes the synthesis of some new five- seven heterocyclic rings derived from benzenesulfonylhydrazide as starting material. Its condensation with 4-methoxy and 4nitro benzaldehyde gives the Schiff bases (1a,b). Schiff bases were reacted with cyclic anhydrides given Oxazepine, Thiazepine derivatives(2,3,4 a,b)(seven membered ring) and with 2-mercapto benzoic acid gives thiazine derivatives (6a,b)(six membered ring) finally with thioglycolic acid give thiazolidine ring(five membered ring) scheme(3). The synthesized compounds have been characterized by melting points,FT-IR, 1H-NMR spectroscopy ,13CNMR and Elemental analysis. some of synthesized compounds were tested for their antibacterial activity
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