Synthesis and biological evaluation of some 1,3‐benzoxazol‐2(3H)‐one hybrid molecules as potential antioxidant and urease inhibitors

• Published in: Journal of heterocyclic chemistry 2021-01, Vol.58 (1), p.260-269
• Main Authors: Yilmaz, Fatih, Menteşe, Emre, Sökmen, Bahar Bilgin
• Format: Article
• Language: English
• Subjects: Antioxidants; Chemical synthesis; Coumarin; Radicals; Scavenging; Thiadiazoles; Triazoles
• ISSN: 0022-152X; 1943-5193
• DOI: 10.1002/jhet.4165

A new series of 1,3‐benzoxazol‐2(3H)‐one hybrid compounds, including coumarin, isatin 1,3,4‐triazole and 1,3,4‐thiadiazole moieties, were synthesized and biologically evaluated for their antioxidant capacities and anti‐urease properties. The synthesized benzoxazole‐coumarin (6a–e) and benzoxazole‐isatin (10a–c) hybrids showed remarkable urease inhibitory activities with IC50 (μM), ranging from 0.0306 ± 0.0030 to 0.0402 ± 0.0030, while IC50 of standard thiourea is 0.5027 ± 0.0293. The synthesized benzoxazole‐triazole (8a–c) and benzoxazole‐thiadiazole (9a–c) hybrids showed similar urease inhibitory activities with IC50 (μM), ranging from 0.3861 ± 0.0379 to 0.5126 ± 0.0345. The antioxidant activity of the synthesized compounds was evaluated for their antioxidant activities, such as reducing power and ABTS (2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulphonic acid) diammonium salt) radical scavenging. The results of ABTS radical scavenging activities of some of the synthesized molecules showed higher activities than standard Trolox, SC50 (μM) = 213.04 ± 18.12. One benzoxazole‐coumarin (6f), two benzoxazole‐isothiocyanate (7b, 7c), and two benzoxazole‐triazole (8b, 8c) derivatives showed higher activities (SC50 (μM) values, 82.07 ± 10.34, 120.19 ± 7.30, 104.58 ± 10.55, 153.26 ± 7.14, and 144.82 ± 10.68, respectively) than standard Trolox, (SC50 (μM) = 213.04 ± 18.12).