Synthesis and characterization of azetidin-2-one and 1,3-oxazepine derivatives using Schiff bases derived from 1,1’-biphenyl-4,4’-diamine

The present study included the synthesis of two series of heterocyclic compounds, azetidin-2-one and 1,3-oxazepine derivatives. All synthesized compounds were characterized using FT-IR and 1H NMR spectra. The study was divided into two parts. The first synthesis Schiff bases derivatives (1-4) via the condensation reaction of 1,1′-biphenyl-4,4′-diamine (A) with benzaldehyde derivatives (2,5-dimethoxybenzaldehyde, 4-hydroxy-3-methoxybenzaldehyde, furan-2-carbaldehyde and 3-hydroxybenzaldehyde). The second synthesis azetidine-2-one derivatives (5-8) from the reaction of Schiff bases with chloroacetyl chloride. Schiff bases also reacted with maleic anhydride to yield 1,3-oxazepine derivatives (9-12).

Preparation of modified polysulfone material decorated by sulfonated citric chitosan for haemodialysis and its haemocompatibility

Polysulfone (PSF) works potentially in haemodialysis due to its great mechanical and chemical stability, but performs poorly in haemocompatibility. For promoting the unpleasant haemocompatibility, sulfonated citric chitosan (SCACS) with the structure and groups similar to heparin was primarily synthesized by acylation and sulfonation. Furthermore, the chloroacylated PSF was pretreated by electrophilic chloroacetyl chloride to achieve more active sites for further reaction; the following membranes underwent the amination and were named amination polysulfone (AMPSF) membranes. Moreover, SCACS with abundant carboxyl and sulfonic groups was covalently grafted at the surface of pretreated PSF membranes, called PSF-SCACS membranes. The PSF-SCACS membranes were successfully synthesized and characterized by 1 H NMR, ATR-FTIR and XPS. In addition, the water contact angle of PSF-SCACS membranes decreased by 47° and the morphologies of the membranes changed little compared with the unmodified PSF membranes. The haemocompatible testing results, including protein adsorption, platelet adhesion, haemolysis rate, plasma recalcification time, activated partial thromboplastin time (APTT), prothrombin time (PT) and thrombin time (TT), demonstrated that the PSF-SCACS membranes possessed excellent haemocompatible performances, and SCACS played an important role in the modification.

Synthesis Characterization and Studying Antibacterial Activity of some New Pyrazol Derivatives

This research involved the conversion of sulfadiazine into compound 2-chloro-N-(4-(N-(pyrimidin-2-yl) sulfamoyl) phenyl) acetamide [A] through the reaction of sulfadiazine with chloroacetyl chloride in the presence of diethylamine in dimethylformamide as solvent. Then prepared the hydrazine derivative of sulfadiazine 2-hydrazinyl-N-(4-(N-(pyrimidin-2-yl) sulfamoyl) phenyl) acetamide [B] through the interaction of compound [A] with hydrazine in dimethylformamide as solvent. Followed by chalcones preparation [C1, C2, C3, C4, and C5] from the reaction of 4-aminoacetophenone with some aromatic aldehydes in a basic medium in absolute ethanol using an ice bath. Pyrazoline derivatives [BC1, BC2, BC3, BC4, and BC5] were prepared from the reaction of the hydrazine derivative of sulfadiazine [B] with chalcones in a basic medium in the presence of absolute ethanol. The pyrazole derivatives [IBC1, IBC2, IBC3, IBC4, and IBC5] were prepared from the reaction of the hydrazine derivative of sulfadiazine [B] with chalcones in the presence of glacial acetic acid and then the product was oxidized using Iodine. Synthesized compounds have been studied by their melting points, and characterized by C.H.N.S analysis, FT-IR and 1H-MNR spectroscopy and studied of biological activity.

Separation and Rectification of Chloroacetyl Chloride from TiCl4

Titanium tetrachloride (TiCl4) is an important intermediate material for the preparation of titanium products. The organic impurities in TiCl4 are easily accumulated during the production of titanium sponges due to the problems of imperfect detection methods and the lack of effective control methods, resulting in a poor quality of sponge titanium. Among all impurities, chloroacetyl chloride (CAC) is the most important in TiCl4. Herein, the determination of the CAC content in TiCl4 solution, with a low detection limit of 0.633 ppm, was established by the standard addition method using Fourier transform infrared (FTIR) spectrometry. This test method presented good repeatability, excellent accuracy, and moderate precision. Furthermore, the influencing factors of CAC separation in the continuous rectification process, including the heating power (the ratio of total heating power to feed rate), reflux temperature, top tower pressure, and feed temperature were optimized based on an orthogonal experimental design. The experimental data demonstrated that the average CAC removal rate reached 78.94% ± 1.00% under the optimal distillation conditions, with 72.21% of the CAC removed via the off-gas system. Therefore, excellent control of the negative pressure of the tail gas is highly desirable for the removal of CAC impurities.

Synthesis and spectral characterization of some new thiazolopyrimidine derivatives

Thiazolopyrimidnes are considered one of the most interesting classes in heterocyclic chemistry due to their pharmaceutical importance. Herein, we report the synthesis of some new heterocyclic compounds containing thiazolopyrimidine starting from compound (1) which was previously prepared in literature. The starting compound was allowed to react with different alkylating agents such as chloroacetone, chloroacetyl chloride, and phenacyl bromide to afford derivatives (2-4). Compound (5), benzylidene derivative, was obtained by the reaction of compound (2) with benzaldehyde while amino-dicarbonitrile compound (6) can be obtained by the reaction of compound (5) and malononitrile. Acetylation of amino group in compound (6) with chloroacetyl chloride led to formation of compound (7). Nucleophilic substitution of chlorine in compound (7) by aniline gave compound (8) which further subjected the Munich reaction to form compound (9). All new synthesized compounds were characterized using different elemental and spectral analysis.

A facile method to synthesize vildagliptin

An efficient and high-yielding synthetic method for the preparation of vildagliptin via four steps is reported. The process starts from L-proline and involves a successful reaction with chloroacetyl chloride in tetrahydrofuran to afford ( S)-1-(2-chloroacetyl)pyrrolidine-2-carboxylic acid, followed by a reaction with acetonitrile in the presence of sulfuric acid to give ( S)-1-(2-chloroacetyl)pyrrolidine-2-carbonitrile. This is then reacted with 3-aminoadamantanol to give vildagliptin. 3-Aminoadamantanol is prepared from 1-aminoadamantane hydrochloride via oxidation with sulfuric acid/nitric acid and boric acid as the catalyst followed by ethanol extraction. The overall yield is 95%.

One-pot synthesis of 3-substituted-4H-[1,2,3] triazolo[5,1-c][1,4]oxazin-6(7H)-ones from propargyl alcohols, chloroacetyl chloride, and sodium azide

An efficient, one-pot synthesis of 3-substituted-4 H-[1,2,3]triazolo[5,1- c][1,4]oxazin-6(7 H)-ones is developed via sequential esterification, substitution, and 1,3-dipolar cycloaddition processes of various propargyl alcohols, chloroacetyl chloride, and sodium azide. This method provides a variety of novel 1,2,3-triazole-fused oxazinones and has several advantages including simple operation, high efficiency, and good-to-excellent product yields (80%–95%) without the need to isolate the ester and azide intermediates.

On the Acylation of 1,6-Diamino-2-oxo-1,2-dihydropyridine-3,5-dicarbonitriles

Here, 1,6-diamino-2-oxo-1,2-dihydropyridine-3,5-dicarbonitriles, prepared by the reaction of cyanoacethydrazide with arylmethylene malononitriles, react with 1-cyanoacetyl-3,5-dimethylpyrazole and chloroacetyl chloride to give corresponding cyanoacetamides and chloroacetamides. The reaction with phthalic anhydride proceeds under harsh conditions to give 4,7-dioxo-4,7-dihydropyrido[1′,2′:2,3][1,2,4]triazolo[5,1-a]isoindole- 1,3-dicarbonitriles.

Synthesis of New Water-Soluble Bunte Salts Bearing Thieno[2,3-b]Pyridine-3-yl Substituents

Upon treatment with chloroacetyl chloride, 3-aminothieno[2,3-b]pyridines gave the corresponding chloroacetamides. The latter readily react with sodium thiosulphate to afford water soluble S-alkylthiosulphates with pharmacophoric heterocyclic units.

New Quinoxaline-1,4-Dioxides Derived from Beirut Reaction of Benzofuroxane with Active Methylene Nitriles

Benzofuroxane reacts under Beirut reaction conditions with active methylene nitriles to give new 2-aminoquinoxaline-1,4-dioxides. The treatment of known 2-amino-3-cyanoquinoxaline-1,4-dioxide with chloroacetyl chloride afforded corresponding chloroacetamide which is useful for the preparation of various heterocycles bearing a quinoxaline-1,4-dioxide core system.