Abstract

Firstly, thiosemicarbazides were prepared by the reaction of hydrazine monohydrate with isothiocyanates in cold dry ethanol at 0 °C for 1 h. After that, new isatin-β-thiosemicarbazones were synthesized by treatment of 5-methoxyisatin with thiosemicarbazides in aqueous ethanol containing one drop of hydrochloric acid at reflux for 3 h. The chemical structures of products were confirmed by means of IR, ¹H NMR, and ¹³C NMR data and by elemental analysis. All the synthesized compounds were evaluated for their antioxidant activity by 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging method. The synthesized molecules showed lower antioxidant activity than the standard Trolox (8.757 μM). IC₅₀ values of the newly synthesized isatin-β-thiosemicarbazone derivatives ranged from 12.455 to 73.471 μM.

Graphic abstract

中文翻译：

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某些新的N 4-芳基取代的-5-甲氧基Isatin-β-thiosemicarbazone衍生物的合成，表征和抗氧化活性

摘要

首先，通过使一水合肼与异硫氰酸酯在冷的干燥乙醇中于0°C下反应1 h来制备硫代氨基脲。之后，通过在含有一滴盐酸的乙醇水溶液中用硫代氨基甲酰肼在回流条件下处理3个小时，用5-甲氧基异族酰亚胺合成了新的isatin- β- thiosemicarbazones。产物的化学结构通过IR，¹ H NMR和¹³ C NMR数据以及通过元素分析确认。通过1，1-二苯基-2-吡啶基肼基（DPPH）自由基清除方法评价所有合成的化合物的抗氧化活性。合成的分子显示出比标准Trolox（8.757μM）低的抗氧化活性。新合成的isatin-的IC ₅₀值β-硫代半碳杂a衍生物的范围为12.455至73.471μM。

图形摘要