This research includes synthesis of new heterocyclic derivatives of N-benzyl-5-bromoisatin. New 1, 2, 4-triazole, oxazoline and thiazoline derivatives of [N-benzyl-5-bromo-3-(Ethyliminoacetate)-indole-2-one] (2) have been synthesized. The preparation process started by the reaction of 5-bromoisatin with sodium hydride in dimethylformamide (DMF) at 0°C, gave suspension of sodium salt of 5-bromoisatin and subsequent reaction with benzylchloride to give N-benzyl-5-bromoisatin (1). Compound (1) reacted with ethylglycinate (Schiff base) obtained the intermediate compound (2) which reacted with different reagents in two ways. The first way, compound (2) reacted with (hydrazine hydrate, semicarbazide, phenylsemicarbazide and thiosemicarbazide), then converted to (hydrazide, semicarbazide, phenylsemicarbazide and thiosemicarbazide) derivatives respectively to give compounds (3-6). After that compounds (4-6) cyclized in presence of alkaline media (4N-NaOH) to form substituted 1, 2, 4-triazole derivatives (7-9). In alkaline media (20%KOH) compound (3) reacted with CS2 to give potassium salt (10) that reacted with excess of hydrazine hydrate to give compound (11). The second way includes reaction of compound (3) with (phenylisocyanate and phenylisothiocyanate) to give compound (5 and 12), which undergo cyclization with p-bromophenacylbromide to obtain oxazoline (13) and thiazoline (14). Newly synthesized compounds were identified via spectral methods; their [FTIR and some of them by 1HNMR, 13C-NMR] and measurements of some of its physical properties and also some specific reactions. Furthermore the effects of the synthesized compounds were studied on some strains of bacteria.
New 2-amino thiazole ,oxodiazole, sulphonilamide and diazin derivatives of N-(α-chloro aceto)-3-(tolyl imino)-5-bromo-2-oxo-indole(2) have been synthesized .The preparation process started by the reaction of 5-bromo isatin with P-toluidine in the presence of glacial acetic acid and dimethylformamide(DMF) as a solvent to give 3-(tolyl imino)5-bromo-1H-indole-2-one.(1), Compound (1) with sodium hydride in dimethylformamide(DMF) at 0C0 gave a suspension of the sodium salt of Schiff base derivative and subsequent reaction with monochloroacetylchloride obtained the intermediate compound(2).Compound(2) was reacted with different reagents in four routes.The first route involved direct reaction with substituted 2-aminobenzothiazole u
... Show MoreThis research includes the synthesis of some new different heterocyclic derivatives of 5-Bromoisatin. New sulfonylamide, diazine, oxazole, thiazole and 1,2,3-triazole derivatives of 5-Bromoisatin have been synthesized. The synthesis process started by the reaction of 5-Bromoisatin with different reagents to obtain schiff bases of 5-Bromoisatin intermediate compounds(1, 8, 19) by using glacial acetic acid as a catalyst in three routes. The first route, 5-Bromoisatin reacted with p-aminosulfonylchloride to product compound(1), then converted to sulfonyl amide derivatives(2-7) by the reaction of compound(1) with different substituted primary aromatic amine in absolute ethanol. The second route includes the reaction of 5-Bromoisatin rea
... 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 MorePM3 and DFT (B3LYP) with a 6-311++G (2d, 2p) level of theoretical quantum mechanical calculations were employed to give investigation into the inhibition efficiency of the two new N-phenyl-ethylidene-5-bromo isatin derivatives which are N-phenyl-ethylidene-5-bromo-3[(imine aceto) urea]-2-oxo indole (NPEO) and N-phenyl-ethyeidine-5-bromo-3[(imine aceto) thiourea]-2-oxo indole (NPES). The calculated physical properties and quantum chemical parameters correlated to the inhibition efficiency all are studied and discussed at the equilibrium geometry in a vacuum, dimethyl sulfoxide and aqueous at their correct symmetry.
Isatin (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 MoreA 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
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A new series of bases of Schiff (H2-H4) derived from phthalic anhydrideweresynthesized. These Schiff bases were prepared by the reaction of different amines (tyrosine methyl ester, phenylalanine methyl ester, and isoniazid) with the phthalimide derived aldehyde with the aid of glacial acetic acid or triethylamine ascatalysts. All the synthesized compounds were characterized by (FT-IR and 1HNMR) analyses and were in vitro evaluated for their antimicrobial activity against six various kinds of microorganisms. All the synthesized compounds had been screened for their antimicrobial activity against two Gram-positive bacteria “Staph. Aureus, and Bacillus subtilis
... Show MoreThis 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
... Show MoreIn search of novel antibacterial agent, a series of new isatin derivatives (3a-d) have been synthesized by condensation isatin (2,3-indolinendione) with piperidine (hexahydropyridine), hydrazine hydrate and Boc-amino acids respectively. Compounds synthesized have been characterized by IR spectroscopy and elemental analysis. In addition, the in vitro antibacterial properties have been tested against E. coli, P. aeruginosa, and Bacillus cereus, S. aureus by employing the well diffusion technique. A majority of the synthesized compounds were showing good antibacterial activity and from comparisons of the compounds, compound 3d has been determined to be the most active compound.
This research included the preparation of 2-mercaptobenzoxazole (N1) by the reaction of ortho-aminophenol with carbon disulfide in an alcoholic potassium hydroxide solution. The 2-mercapto benzoxazole (N1) was then treated with hydrazine to obtain the 2-hydrazino benzoxazole (N2). A number of hydrazones (N3-N5) were prepared through the reaction of N2 with different benzaldehydes. The compound (N6) was also prepared whereby the ring closing of hydrazone (N3) using chloroacetylchloride, while the compound (N7) was prepared by treating 2-hydrazino benzoxazole with acetylacetone. When the compound (N1) was treated with formaldehyde, it afforded the compound (N8). Also, the N9 was obtained from the reaction of N1 with chloroacetic acid in th
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