Synthesis, structural and crystallographic characterization of new hydrosoluble thymol derivatives with a comparative study of enhanced antioxidant activity

In this study, we synthesized two new Thymol derivatives obtained by reacting Thymol sulfonic acid with respectively two amines: aniline and diethylamine. Spectroscopic analysis by FT-IR, mass spectrometry, (1H, 13C) NMR and XRD elucidated the chemical structure of these two new Thymol derivatives identified as: Diethylammonium 4-hydroxy-5-isopropyl-2-methylbenzenesulfonate (P.1) and Benzenaminium 4-hydroxy-5-isopropyl-2-methylbenzenesulfonate (P.2) obtained respectively with 98% and 52% reaction yields. They match two new Thymol organic salts with specific ionic crystalline form. We investigated a comparative antioxidant activity study based on the DPPH test versus Butyl hydroxy toluene (BHT) as control and Thymol as strating material. The results show that boat synthesized compounds (P.1) and (P.2) are significantly more active with IC50 value 3,44 µg/mL for (P.2) and 6,76 µg/mL for (P.1) versus 21,7 µg/mL for (BHT) and 178.03 µg/mL for Thymol. More interestingly, these two compounds are water soluble and the compound (P.1) was obtained in a good yield reaction (98%)