No abstract

In this study 1-[4-(2-methoxy benzyl)-6-aryl-pyridazin-3(2H)-ylidene] hydrazines were used for the synthesis of new heterocyclic systems such as thiazolidine, phthalazine, pyrazolo, tetrazolo, hydrazide and new pyridazine derivatives to explore the effect of silver nanoparticles on their biological activity efficiency. Structures of the new heterocycles were characterized by the aid of several analytical techniques including; 1 H-NMR, FTIR and mass spectra. Silver nanoparticles were synthesized by a simple methodology and the formation of silver nanoparticles was confirmed by transmission electron microscopy (TEM) and UV studies. Most of the new prepared heterocycles were evaluated in vitro as new antimicrobial agents. Combination effects of the silver nanoparticles on the antimicrobial activity of the new heterocycles were investigated using the disk diffusion method. Compound 10a exhibited the strongest enhancing effect of silver nanoparticles solution against Aspergillus flavus and Candida albicans.

Various pyridazin‐3(2H)‐ones, 3‐chloropyridazines and pyridazin‐3(2H)‐thiones were synthesized and treated with the sulpha drug (knowing by sulphamethoxazole). All the new compounds were evaluated for their antibacterial activity. They showed significant antibacterial activity against Staphylococcus aureus and Bacillus subtilis (Gram + ve) and E. coli, Pseudomonas aeruginosa and Yersinia enterocolitica (Gram ‐ ve) bacteria by agar plate diffusion method. All proposed structures were confirmed by IR, 1H NMR, Mass spectra and Elemental analysis.

Chitosan is one of the most studied polysaccharides nowadays. Because it is non-toxic, widely used in food, pharmaceutical processes, agricultural, and presents excellent biological properties such as biodegradation in the human body, and antibacterial. In the present study we reported the extraction of low cost chitosans (Cs1, Cs2, Cs3 and Cs4) from shrimp shells by extraction of chitin (Egypt: case study), then alkaline deacetylation of chitin with strong alkaline solution at different period of time. The different prepared chitosans (Cs1, Cs2, Cs3 and Cs4) were characterized by FTIR spectroscopy, thermal stability, morphology, crystallography, elemental analysis and degree of deacetylation. The data showed that the prepared chitosan Cs2 has the most thermal stability and the highest degree of deacetylation.

No abstract

No abstract

No abstract

No abstract