New heterocyclic systems: Pyrido[2′,3′:5,4]thieno(furo)[3,2-<i>d</i>]oxazines as intermediate compounds for the synthesis of substituted pyrido[3′,2′:4,5]thieno(furo)[3,2-<i>d</i>]pyrimidines
作者:Samvel N. Sirakanyan、Domenico Spinelli、Athina Geronikaki、Elmira K. Hakobyan、Anush A. Hovakimyan
DOI:10.1080/00397911.2019.1644656
日期:——
acids of thieno(furo)[2,3-b]pyridines derivatives by refluxing in acetic anhydride a new heterocyclic system were obtained: 9(10)-methylpyrido[3',2':4,5]thieno(furo)[3,2-d][1,3]oxazin-7(8)-ones (65−89%). Finally the reaction of these latter compounds with benzyl amine or with hydrazine hydrate led to the formation of pyrimidine derivatives: 8(9)-benzyl-9(10)-methylpyrido[3',2':4,5]thieno(furo)[3,2
摘要 以1-氨基噻吩并(呋喃)[2,3-b]吡啶-2-羧酸乙酯1为原料,通过碱水解得到相应的噻吩并(呋喃)[2,3-b]吡啶钾盐2。继续研究相关酸(通过用盐酸处理),我们观察到虽然噻吩并 [2,3-b] 吡啶转化为 1-氨基噻吩并 [2,3-b] 吡啶-2-羧酸 3a-h相比之下,呋喃[2,3-b]吡啶的衍生物以良好的产率(71-80%)得到呋喃[2,3-b]吡啶-1-酮5(70-75%)。此外,从噻吩并(呋喃)[2,3-b]吡啶衍生物的钾盐或氨基酸开始,通过在乙酸酐中回流,获得了新的杂环系统:9(10)-甲基吡啶并[3',2': 4,5]噻吩(呋喃)[3,2-d][1,3]oxazin-7(8)-ones (65-89%)。最后这些化合物与苄胺或水合肼的反应导致嘧啶衍生物的形成:8(9)-苄基-9(10)-甲基吡啶并[3',2':4,5]噻吩并(呋喃) [3,2-d]pyrimidin-7(8)-ones