An experimental and computational study of antioxidant activity of N‐phenylthiourea and N‐phenylselenourea analogues. Issue 4 (23rd August 2019)

• Record Type: Journal Article
• Authors: Huong, Dinh Quy; Duong, Tran; Nam, Pham Cam
• Is Part Of: Vietnam journal of chemistry. Volume 57:Issue 4(2019)
• Page Start: 469
• Page End: 479
• Publication Date: 2019-08-23
• Subjects: N‐phenylthiourea -- N‐phenylselenourea -- antioxidant -- DPPH radical scavenging ability -- bond dissociation energy -- ionization energy -- potential energy surface; Chemistry -- Periodicals; 540
• DOI: 10.1002/vjch.201900091
• Languages: English
• ISSNs: 0866-7144

Abstract

Abstract: The antioxidant performance of N‐phenylthiourea has been experimentally studied via the half maximal inhibitory concentration value (IC50 ) in combination with quantum calculations. In the experimental part, DPPH (1, 1‐diphenyl‐2‐picrylhydrazyl) radical scavenging ability of N‐phenylthiourea (IC50 ) was measured to be 4.82.10 ‐4 M. Based on three antioxidant mechanisms being hydrogen atom transfer (HAT), single electron transfer followed by proton transfer (SETPT) and sequential proton loss electron transfer (SPLET), the essential thermoparameters of N‐phenylthiourea derivatives were carried out at ROB3LYP/6‐311++G(2df, 2p)//B3LYP/6‐311G(d, p) in both gas phase and ethanol in order to evaluate their antioxidant capacity. For the sake of comparison, N‐phenylselenourea derivatives were also taken into account. The computational results indicated that the antioxidant of N‐phenylselenourea is better than that of N‐phenulthiourea. Besides, potential energy surfaces of N‐phenylselenourea derivatives and HOO radical were investigated. All the reactions were thermodynamically favored. The derivatives containing the electron donating group at the para position of N‐phenylselenourea considerably enhanced their antioxidant capacity. As a result, para ‐N(CH3 )2 ‐C6 H4 ‐NH‐CSe‐NH2 was the best potential antioxidant in the studied compounds.