Synthesis and biological evaluation of novel fused triazolo[4,3-$a$] pyrimidinones

Authors : Ikhlass Abbas, Sobhi Gomha, Mohamed Elneairy, Mahmoud Elaasser, Bazada Mabrouk

Pages : 510-531

Doi:10.3906/kim-1501-144

View : 17 | Download : 11

Publication Date : 9999-12-31

Article Type : Makaleler

Abstract :The reaction of thione 3 or its 2-methylthio derivative 4 with hydrazonoyl halides 5a-l, in the presence of triethylamine, yielded the corresponding triazolo[4,3-$a$]pyrimidin-5(1$H)$-ones 8a-l. The structure of compounds 8a-l was further confirmed by the reaction of 3 with the appropriate active chloromethylenes 11a-c followed by coupling of the products with benzenediazonium chloride to afford the azo-coupling products 6b, f, and j, which were converted in situ to 8b, f, and j. 2-Hydrazinyl-pyrido[3',2':4,5]thieno[3,2-$d$]pyrimidin-4(3$H)$-one (13) was prepared and condensed with different aldehydes 14a-f to give the corresponding hydrazone derivatives 15a-f. Oxidative cyclization of the hydrazones 15a-f give the corresponding triazolo[4,3-$a$] pyrimidin-5(1$H)$-one derivatives 16a-f.
Keywords : The antimicrobial activity of the products was evaluated and the results revealed that compounds 8f and 15f showed strong activity against gram-positive bacteria while compound 15d showed the highest activity against gram-negative bacteria. Moreover, co