Synthesis, spectroscopic studies, and antioxidant activities of novel thio/carbohydrazones and bis-isatin derivatives from terephthalaldehyde

MUĞLU H., Yakan H., BAKIR T. K.

TURKISH JOURNAL OF CHEMISTRY, vol.44, no.1, pp.237-256, 2020 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 44 Issue: 1
  • Publication Date: 2020
  • Doi Number: 10.3906/kim-1910-13
  • Journal Name: TURKISH JOURNAL OF CHEMISTRY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Chemical Abstracts Core, TR DİZİN (ULAKBİM)
  • Page Numbers: pp.237-256
  • Keywords: Isatin, carbohydrazone, Schiff bases, DPPH, spectroscopic techniques, MANNICH-BASES, ANTIVIRAL ACTIVITY, ANTI-HIV, SCHIFF BASES, ANTIBACTERIAL, ANTIFUNGAL, CARBOHYDRAZONE, HYDRAZONES
  • Ondokuz Mayıs University Affiliated: Yes

Abstract

New bis(isatins-thio/carbohydrazones) based on Schiff bases were prepared from terephthalaldehyde biscarbohydrazone and 5-substituted isatins in the presence of a drop of sulfuric acid under reflux in ethanol. Terephthalaldehyde bis(thio/carbohydrazone) was synthesized by the reaction of (thio)/carbohydrazide and terephthalaldehyde in the presence of a few drops of acetic acid under reflux in ethanol. The structures of these synthesized compounds were determined using IR, H-1 NMR, and C-13 NMR spectroscopy and elemental analysis. The in vitro antioxidant activity of all the compounds was determined by the 1,1-diphenyl-2-picryl hydrazyl (DPPH center dot) free radical scavenging method. Compound 2 showed the best antioxidant activity.