@inproceedings{paperid:1035426, author = {Bakavoli, Mehdi and Akbarzadeh, Marzieh and Eshghi, Hossein and Rahimizadeh, Mohammad and Shiri, Ali}, title = {Synthesis of new heterocyclic system: [1,3]oxazolo[4,5-d] [1,2,4]triazolo[4,3-a] pyrimidine}, booktitle = {20th Iranian Seminar of Organic Chemistry}, year = {2013}, location = {همدان, IRAN}, keywords = {Fused pyrimidines such as oxazolopyrimidines have attracted increasing interest because of their diverse biological activities such as anti-inflammatory; analgestic and antimicrobial agents.[1-3] Regarding these points; it seems to need for identification of novel structure that may be of use in designing new; potent and effective pharmacological active compounds like 1;2;4-triazole moieties fused to oxazolo[4;5-d]pyrimidine ring at 6;7 position. In this study; 2;4-dichloro-4-nitro-6-methyl-pyrimidine (1) was reduced with iron to give the amino derivative (2). Compound (2) was treated with various derivatives of arylcarboxylic acids to obtain quantitatively the cyclized products 3(a-h) as precursors. The subsequent reaction of compounds 3(a-h) with hydrazine hydrate and treatment with some triethylorthoesters attained the corresponding novel heterocyclic system of [1;3]oxazolo[4;5-d][1;2;4]triazolo[4;3-a]pyrimidine derivatives 5(a-x) in good to excellent yields.}, }