@article{article_639080, title={Free-Radical Scavenging Activities of 2-Benzoxazolinone Derivatives Containing Thiosemicarbazide, Triazole, Thiadiazole and Hydrazone Units}, journal={Hacettepe University Journal of the Faculty of Pharmacy}, pages={27–50}, year={2011}, author={Çiftci, Samiye Yabanoğlu and Kelekçi, Nesrin Gökhan and Gökşen, Umut Salgın and Uçar, Gülberk}, keywords={Free-Radical Scavenging Activity, 2-Benzoxazolinone Derivatives, 2, 2-diphenyl-1-picrylhydrazyl, superoxide radical, hydrogen peroxide, nitric oxide}, abstract={It has been reported that some benzoxazolinone, triazole, thiadiazole and hydrazone derivatives showed significant analgesic and antiinflammatory activity. It has been speculated that non-steroidal antiinflammatory agents NSAIDs can act as the free radical scavengers and show antioxidant activity. It is also well documented that oxidative stres can play an important role in the side effects of many xenobiotics including NSAIDs. Therefore, in the present study, it was thought that the combination of different pharmacophores in one frame may lead to compounds with interesting pharmacological profiles and the effects of thiosemicarbazide, triazole, thiadiazole and hydrazone bearing 2-benzoxazolinone were investigated on free radical scavenging activity. Antioxidant activities of the novel compounds were evaluated by the determinations of 2,2-diphenyl-1-picrylhydrazyl DPPH radical scavenging activity, superoxide radical scavenging activity, hydrogen peroxide scavenging activity, nitric oxide scavenging activity and reducing power. The various antioxidant activities were compared to standard antioxidants such as butylated hydroxytoluen and ascorbic acid and the results were expressed as IC50 values. All of the newly synthesized compounds exhibited varying degrees of scavenging capacity on different active radicals; the compounds 13-18 hydrazone derivatives proved to be most active. Among those, compound 17 and 18, having p-methoxy and -hydroxyl groups on their phenyl rings, respectively showed the highest scavenging capacity of active radical species. These preliminary in vitro results may contribute to explain the potency of antiinflammatory activity of the compounds.}, number={1}, publisher={Hacettepe University}