Ring closure reactions of 5-azidopyrido[2,3-<i>d</i>]pyrimidinetriones to isoxazolo- and oxadiazolopyrido[2,3-<i>d</i>]pyrimidinetriones
作者:Dang Van Tinh、Wolfgang Stadlbauer
DOI:10.1002/jhet.5570450621
日期:2008.11
Thermal decomposition of 5-azidopyrido[2,3-d]pyrimidines 2 and 7 having reactive ortho-substituents such as a formyl or a nitro group yielded isoxazolo[3′,4′:4,5]pyrido[2,3-d]pyrimidines 3 or oxadiazolo-[3′,4′:4,5]pyrido[2,3-d]pyrimidines 9. The reaction conditions of the azide decomposition were studied by differential scanning calorimetry (DSC). In addition, desoxygenation of N-oxides 9 to oxadiazoles
具有反应性邻位取代基(如甲酰基或硝基)的5-叠氮基吡啶并[2,3 - d ]嘧啶2和7的热分解生成异恶唑并[3',4':4,5]吡啶并[2,3- d ]嘧啶3或恶二唑-[3',4':4,5]吡啶[2,3- d ]嘧啶9.通过差示扫描量热法(DSC)研究了叠氮化物分解的反应条件。另外,研究了将N-氧化物9脱氧为恶二唑10和将叠氮化物7区域选择性还原为胺8。