title: Synthesis of novel Schiff's bases of highly potential biological activities and their structure investigation.
abstract: Novel bisaldehyde-hydrazide Schiff's bases AS1 (2,2'-(ethane-1,2-diylbis(oxy))dibenzaldehyde terephthalohydrazide) and AS2 (N',N'″-(((ethane-1,2-diylbis(oxy))bis(2,1-phenylene))bis(methanylylidene))di(benzohydrazide)) were prepared as new macrocyclic compounds via condensation reactions. AS1 had been prepared by condensation between (2,2'-(ethane-1,2-diylbis(oxy))dibenzaldehyde) bisaldehyde and terephthalohydrazide in a ratio1:1. AS2 had been obtained by condensation between (2,2'-(ethane-1,2-diylbis(oxy))dibenzaldehyde) bisaldehyde and benzohydrazide in ratio 1:2. The structures of AS1 and AS2 were characterized by elemental analysis (EA), mass (MS), FT-IR and (1)H-NMR spectra, and thermal analyses (TG, DTG). The activation thermodynamic parameters such as ΔE(∗), ΔH(∗), ΔS(∗) and ΔG(∗) were calculated from the TG curves using Coats-Redfern method. It is important to investigate their molecular structures to know the active groups and weak bonds responsible for their biological activities. Consequently in the present work, the obtained thermal (TA) and mass (MS) practical results are confirmed by semi-empirical MO-calculations (MOCS) using PM3 procedure. Their biological activities had been tested in vitro against Escherichia coli, Proteus vulgaris, Bacillus subtilis and Staphylococcus aurous bacteria in order to assess their anti-microbial potential.
authors.affiliation: Green Chemistry Department, National Research Centre, Dokki, 12622 Giza, Egypt.
authors.forename: Ehab M
authors.initials: EM
authors.lastname: Zayed
authors.affiliation: Chemistry Department, Faculty of Science, Cairo University, 12613 Giza, Egypt. Electronic address: mazayed429@yahoo.com.
authors.forename: M A
authors.initials: MA
authors.lastname: Zayed
mesh_terms: D000900:Anti-Bacterial Agents / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology; D001412:Bacillus subtilis / Q000187:drug effects; D001547:Benzaldehydes / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology; D004926:Escherichia coli / Q000187:drug effects; D006834:Hydrazines / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology; D008958:Models, Molecular; D015394:Molecular Structure; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D012545:Schiff Bases / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology; D013237:Stereoisomerism; D013296:Streptococcus pneumoniae / Q000187:drug effects; D013816:Thermodynamics
chemical_list: C000604636:2,2'-(ethane-1,2-diylbis(oxy))dibenzaldehyde terephthalohydrazide; D000900:Anti-Bacterial Agents; D001547:Benzaldehydes; D006834:Hydrazines; C000604638:N',N''-(((ethane-1,2-diylbis(oxy))bis(2,1-phenylene))bis(methanylylidene))di(benzohydrazide)); D012545:Schiff Bases
keywords: Biological activity; Molecular orbital calculation; Novel bisaldehyde-hydrazide Schiff’s bases; Spectroscopic investigation; Thermal analyses