The corrosion behavior of copper in 0.1 M aqueous sulfuric acid medium has been studied using potentiodynamic polarization measurements, quantum chemical calculations, and molecular dynamic simulations in the presence and absence of (2E,5E)-2,5-dibenzylidenecyclopentanone (M1) and (2E,5E)-bis[(4-dimethylamino)benzylidene]cyclopentanone (M2). The compounds were freshly prepared in high yields via the Claisen–Schmidt reaction between the cyclopentanone and the corresponding aryl aldehyde. The results from the potentiodynamic measurements imply that M1 and M2 act as mixed inhibitors due to their adsorption on the copper surface. The more pronounced corrosion inhibition performance of the M2 molecule in comparison to M1 was related to the fact that this molecule contains two basic nitrogen atoms (in 4-dimethylamino group).
Synthesis of a series of the substituted [(pyridinyl and pyrimidin-2-ylimino)-ethyl]-4-hydroxy-chromen-2-ones and their tetrazole derivates is presented in this study. By catalytic condensation of 4-hydroxy-3-acetylcoumarine 2 and 2-aminopyridines 3(a-d), 3-[(pyridin-2-ylimino)-ethyl]-4-hydroxy-chromen-2-ones 4(a-d) are synthesized in high yield. During the condensation reaction of 2 and 4-amino-2,6-dihydroxypyrimidine 3e, 3-[1-(2,6-Dihydroxy-pyrimidin-4-ylimino)-ethyl]-4-hydroxy-chromen-2-one 4e as condensation products is synthesized. In following series, by cyclization reactions of compounds 4 (a-e) with sodium azide, analogue 3-substituted pyridin-2-yl and pyrimidin-2-yl-5-methyl-2,5-dihydro-1H-tetrazol-5-yl]-4-hydroxy-chromen-2-one 5(a-e) are synthesized the products. Structural characterization of the synthesized products is done on the basis of spectrometric data. Antibacterial activity of the compounds 4(a-e) and 5(a-e) against S. aureus, E. coli and Klebsiella was examined by measuring the inhibition zones around the disks marked with the corresponding products solution. The impact of substitutions in antimicrobial is also explored. Compounds with polar groups have shown significant antibacterial activity against these microorganisms.
4‐(4′‐metoxy‐2‐Benzothiazolylamino)‐3‐nitro‐2H‐[1]‐benzopyran‐2‐one 4a, 4‐(6′‐nitro‐2‐Benzothiazolylamino)‐3‐nitro‐2H‐[1]‐benzopyran‐2‐one 4b, 4‐(6′‐fluoro‐2‐Benzothiazolylamino)‐3‐nitro‐2H‐[1]‐benzopyran‐2‐one 4c and substitued 4‐(1,2,4‐triazolyl‐3‐amino)‐3‐nitro‐2H‐[1]‐benzopyran‐2‐ones 4(d‐e) are synthetized by condensation of 4‐Chlor‐3‐nitro‐2H‐[1]‐benzopyran‐2‐one 2 and corresponding heteroarylamines 3(a–e) under the reflux reaction conditions. Alkali hydrolysis of 4(a–e) afforded the 2‐hydroxy‐ù‐nitroacetophenone 5. Microbiological activity of products 4(a–d) are investigated and results are submitted for their activities against Staphylococcus aureus, Escherichia coli and Clebsiella.
Some new substitued 4‐(2‐benzithiazolylamino‐2H[1]‐pyran‐2‐ones are synthesized by condensation of 2H[1}‐pyran‐2‐ones and corresponding 2‐aminobenzothiazoles. Condensation of 4‐chloro‐6‐methyl‐2H[1]‐pyran‐2‐one 2 and 2‐aminobenzothiazoles 3(a‐c) gave corresponding 4‐(2‐benzothiazolylamino)‐6‐methyl‐2H[1]‐pyran‐2‐ones 4(a‐c). By condensation of 4‐chloro‐3‐nitro‐6‐methyl‐2H[1]‐pyran‐2‐one 6a and 2‐aminobenzothiazoles 3(ad) were synthesized 4‐(2‐benzothiazolylamino)‐3‐nitro‐6‐methyl‐2H[1]‐pyran‐2‐one 6a and 4‐(6‐ethoxy‐2‐benzothiazolylamino)‐3‐nitro‐6‐methyl‐2H[1]‐pyran‐2‐one 6c . The antibacterial activity of products 4(a‐d) against E. coli S. aureus and Clebsiella were investigated. Compounds 4(a‐d) showed light bactericide activity against E. coli, S. aureus and Clebsiella. Compounds 4b and 6d were more active against E. coli. Emphatic activity against S. aureus exhibited compounds 4c and 6d whereas compounds 6a and 6d exhibited the strongest activity against Clebsiella. In general there was a direct positive correlation between increasing concentration of the compound and antibacterial activity.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.