A thiadiazole-based covalent triazine framework nanosheet for highly selective and sensitive primary aromatic amine detection among various amines

The thiadiazole-based covalent triazine framework nanosheet is a first fluorescent sensor that can selectively detect PAAs among various amines.

The application of 1,3-dioxolane in synthesis of disubstituted 3,4-dihydroquinazolines, diarylmethane or methylenediamine

The interaction between 1,3-dioxolane with primary aromatic amine- sulfanilamide (streptocide), secondary aromatic amine-N-benzylaniline and also with amine of heterocyclic series – 4-aminopyridine. It is found that, sulfanilamide (streptocide), which has an electron withdrawing sulfonamide group in para position, reacts with 1,3-dioxolane in an atmosphere of benzol and trifluoroacetic acid producing 3-(4-sulfamoylphenyl)-3,4-dihydroquinazoline-6-sulphonamide, that is corresponding to the previous result obtained when 1,3-dioxolane reacts with para-nitroaniline (which also contains electron-withdrawing nitrogroup) resulting in 3-(p-nitrophenyl)-6-nitro-3,4-dihydroquinazoline. Under the same conditions the interaction between 1,3-dioxolane and N-benzylaniline results in producing 4,4'-bis(phenylmethyleneamino)diphenylmethane, which refers to a different class of compounds – diphenylmethane derivative. A primary amine of heterocyclic series 4-aminopyridine reacts with 1,3-dioxolane in the presence of concentrated hydrochloric acid producing N,Nʹ-di-(4-pyridinyl)methylenediamine. Antimicrobic properties of received compounds were studied on museum potentially pathogenic microorganism strains: Staphylococcusaureus (strain 906), Candid aalbicans (АТСС 24433), in FSBI «Scientific Centre for Expert Evaluation of Medicinal Products» of the Ministry of Health of the Russian Federation. Only N,Nʹ-di-(4-pyridyl)methylenediamine out of three investigated compounds showed microbiological activity. This compound inhibits growth of Staphylococcus aureus at concentration 62.5 µg/ml, culture death comes from the effect of concentration 125.0 µg/ml. The morphology of compounds was established according to mass spectrometry data, 1Н NMR spectroscopy, the structure of N,Nʹ-di-(4-pyridyl)methylenediamine in the form of chloride was proved using X-ray structural analysis.

SYNTHESIS, IN VITRO ANTIMICROBIAL ACTIVITY OF SCHIFF’S BASE, AZETIDINONES AND THIAZOLIDINONES

Objective: The objective of the present study is to synthesize 3-Chloro-4-[3-(2,4-dichloro-5-fluoro phenyl)-1H-pyrazol-4-yl]-1-(substituted) azetidin-2-one [4a-n] and 2-[3-(2,4-Dichloro-5-fluoro phenyl)-1H-pyraol-4-yl]-3-(substituted phenyl)-1,3-thiazolidin-4-one [5a-n]. The structure of all synthesized compounds were characterized by IR, 1H NMR, 13C NMR and mass spectral studies. Methods: The titled compounds 3-Chloro-4-[3-(2,4-dichloro-5-fluoro phenyl)-1H-pyrazol-4-yl]-1-(substituted) azetidin-2-one [4a-n] and 2-[3-(2,4-Dichloro-5-fluoro phenyl)-1H-pyraol-4-yl]-3-(substituted phenyl)-1,3-thiazolidin-4-one [5a-n] were synthesized by the reaction of N-{[3-(2,4-dichloro-5-fluoro phenyl)-1H-pyraol-4-yl] methylene } substituted anilin [3a-n] with chloro acetyl chloride and thioglycolic acid respectively. Compounds N-{[3-(2,4-dichloro-5-fluoro phenyl)-1H-pyraol-4-yl] methylene} substituted aniline [3a-n] were synthesized by the reaction of 3-(2,4-dichloro-5-fluoro phenyl)-1H-pyrazol-4-carbaldehyde [2] with primary aromatic amine in alcohol. All compounds were evaluated for their antimicrobial activity.Results: Compounds 3a,3b,3d,3j,3l,4d,4e,4j,4l,4m,5e,5g,5h,5n exhibited excellent to good antibacterial activity as compared to reference drugs.Conclusion: In summary, N-{[3-(2,4-dichloro-5-fluoro phenyl)-1H-pyraol-4-yl] methylene } substituted anilin [3a-n], 3-Chloro-4-[3-(2,4-dichloro-5-fluoro phenyl)-1H-pyrazol-4-yl]-1-(substituted) azetidin-2-one [4a-n] and 2-[3-(2,4-Dichloro-5-fluoro phenyl)-1H-pyraol-4-yl]-3-(substituted phenyl)-1,3-thiazolidin-4-one [5a-n] derivatives have been synthesized and characterized. In vitro antimicrobial testing of the compounds was carried out by microdilution Method. Amongst the synthesised compounds, many of them had proven their antimicrobial potency which varies from good to excellent.

Synthesis and characterization of several series of 4-acyl-1-[2-aryl-1-diazenyl]piperazines

Five series of a novel class of 4-acyl-1-[2-aryl-1-diazenyl]piperazines have been synthesized and characterized: the 4-acetyl-1-[2-aryl-1-diazenyl]piperazines [series 1]; the 4-cyclohexylcarbonyl-1-[2-aryl-1-diazenyl]piperazines [series 2]; the 4-benzoyl-1-[2-aryl-1-diazenyl]piperazines [series 3]; the benzyl 4-[2-aryl-1-diazenyl]-1-piperazinecarboxylates [series 4]; and the t-butyl 4-[2-aryl-1-diazenyl]-1-piperazinecarboxylates [series 5]. The compounds were synthesized by diazotization of a primary aromatic amine and subsequent coupling to an appropriate secondary amine: 1-acetylpiperazine [series 1]; 1-(cyclohexylcarbonyl)-piperaizine [series 2]; 1-benzoylpiperazine [series 3]; benzyl 1-piperazinecarboxylate [series 4]; and t-butyl piperazine-1-carboxylate (1-BOC-piperazine) [series 5]. The compounds of series 1–5 were characterized by 1H NMR, 13C NMR, high-resolution MS and IR spectroscopy. The model compounds 1,4-di[2-aryl-1-diazenyl]piperazines, and ethyl 4-[2-aryl-1-diazenyl]-1-piperazinecarboxylates were used to facilitate the assignment of the chemical shifts specific to the piperazine ring carbons. HSQC spectra of select compounds established the correlation between proton and carbon resonance signals.

Synthesis of Some new 2-(4-Aryliminophenoxy)N-Arylacetamide Via p-hydroxy benzaldehyde.

Chloroacetamide derivatives (2a-g) have been prepared through reaction of chloroacetyl chloride(1) (which prepared by the reaction of chloroacetic acid with thionyl chloride) with primary aromatic amines and sulfa compounds to afford compounds (2a-g) which then reacted with p-hydroxy benzaldehyde via Williamson reaction to obtaine the new compounds 2-(4-formyl phenoxy)-N-aryl acetamide (3a-g). Finally , compounds (3a-g) will be use as a good synthon to prepare the Schiff bases represented by compounds 2-(4-aryliminophenoxy)-N-arylacetamide (4a-g). through , reaction with some primary aromatic amine. All the prepared compounds were investigated by the available physical and spectroscopic methods.

Synthesis, Characterization and Study of the Biological activity of Some Aldimines Derivatives

A number of imines derivatives have been synthesized, they were obtained by condensation of aromatic aldehyde derivatives with primary aromatic amine derivatives. Their structures have been characterised by IR,1H NMR in addition to the elemental analysis. The biological activity of these imines (which are also known as Schiff bases) were examined against different type of microorganisms and they found to have considerable activity in comparison with the most commonly used antibiotics.