Novel Schiff bases derived from isothiocyanates: synthesis, characterization, and antioxidant activity

Yakan H.

RESEARCH ON CHEMICAL INTERMEDIATES, vol.46, no.8, pp.3979-3995, 2020 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 46 Issue: 8
  • Publication Date: 2020
  • Doi Number: 10.1007/s11164-020-04185-w
  • Journal Name: RESEARCH ON CHEMICAL INTERMEDIATES
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Chimica, Compendex, Environment Index, Index Chemicus (IC)
  • Page Numbers: pp.3979-3995
  • Keywords: Schiff bases, Isothiocyanates, Thiosemicarbohydrazides, Antioxidant activity, Spectroscopic elucidation, IN-VITRO, ANTICANCER ACTIVITY, ANTIVIRAL ACTIVITY, ANTIBACTERIAL, ANTIFUNGAL, ISATIN
  • Ondokuz Mayıs University Affiliated: Yes

Abstract

A series of novel thiosemicarbazones including Schiff bases were synthesized by treatment of various aryl-substituted aldehydes with thiosemicarbazides in ethanol containing one drop of hydrochloric acid at reflux for 3-5 h. For this, thiosemicarbazides were obtained from hydrazine monohydrate and isothiocyanates in cold dry ethanol at 0 degrees C for 1 h. FT-IR,H-1 NMR,C-13 NMR, and LC-MS/MS spectroscopic methods and elemental analysis were used to characterize the identification of the synthesized products. The in vitro antioxidant activity of these compounds was tested by the 1,1-diphenyl-2-picryl hydrazyl (DPPH) free radical trapping method. All of the synthesized compounds showed lower antioxidant activity than the ascorbic acid standard and followed the sequenceI > VII > X > VI > IV > IX > XI > II > V > III > VIII.