Synthesis of new 2(1H)-quinoxalinone derivatives for antimicrobial and antiinflammatory evaluation

New 2(1H)-quinoxalinones and their hexahydro derivatives were prepared for investigating their antimicrobial and antiinflammatory activities. The study showed that thiosemicarbazide 6a derived from the hexahydro-2(1H)-quinoxalinone series has nearly the same antibacterial activity as the reference drug ciprofloxacin. Moreover, the 2(1H)-quinoxalinones bearing N-phenyltriazole (9a) or 4-chlorophenyl-2,3-dihydrothiazole (13b) moieties were the most active ones after 4 h with use of the rat hind paw edema method, whereas their antiinflammatory and ulcerogenic activities were comparable with the selective COX-2 inhibitor celecoxib. Graphical Abstract Synthesis of new 2(1H)-quinoxalinone derivatives for antimicrobial and antiinflammatory evaluation Osama I. El-Sabbagh, Mohamed E. El-Sadek, Sayed M. Lashine, Shada H. Yassin, Sameh M. El-Nabtity In the search for new antimicrobial and antiinflammatory agents, 2(1H)-quinoxalinones and their hexahydro derivatives were prepared. Thiosemicarbazide 6a derived from hexahydro-2(1H)-quinoxalinone showed a high in vitro antibacterial activity while the 2(1H)-quinoxalinone derivative bearing 4-chlorophenyl-2,3-dihydrothiazole moiety 13b exhibited the highest antiinflammatory activity without causing any ulcer side effects like the selective COX-2 inhibitor celecoxib. [graphic removed]