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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Synthesis and anti-staphylococcal activity of new 4-diazopyrazole derivatives
Maria Valeria Raimondi1, Benedetta Maggio, Demetrio Raffa
1Dipartimento di Scienze e Tecnologie Molecolari e Biomolecolari, Sezione di Chimica e Tecnologie Farmaceutiche, Università degli Studi di Palermo, Via Archirafi 32, 90123 Palermo, Italy.
Abstract:
Several new 4-diazopyrazole derivatives 6a-g and 9a-c were obtained by the reaction of 1-(R-substituted-phenyl)-3-(1,3-dimethyl-1H-pyrazol-5-yl)ureas 5a-g and N-(1,3-dimethyl-1H-pyrazol-5-yl)-2-(R-substituted-phenyl)acetamides 8a-c respectively with a sevenfold excess of nitrous acid in acetic acid solution. The compounds were assayed for their activity against the Staphylococcus aureus reference strains ATCC 25923, ATCC 29213 and ATCC 6538, as well as six veterinary strains. The best anti-staphylococcal profile was showed by [(R-substituted-phenyl)acetyl](4-diazonio-1,3-dimethyl-1H-pyrazol-5-yl)azanides 9a,c. Compound 9c was also able at 3.1 μg mL(-1) to inhibit of 45.7% the biofilm formation of the strains S. aureus ATCC 29213.
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