Studies on 6-[(Dimethylamino)methylene]aminouracils: a Facile One-pot Synthesis of Pyrimido[4,5-d]pyrimidines and Pyrido[2,3-d]pyrimidines.
作者:Ashim J. Thakur、Promod Saikia、Dipak Prajapati、Jagir S. Sandhu
DOI:10.1055/s-2001-16036
日期:——
6-[(Dimethylamino)methylene]amino-1,3-dimethyl uracil 1 undergoes formal [4 + 2] cycloaddition reaction with nonconjugated imines to give pyrimido[4,5-d]pyrimidines 3. When reacted with conjugated imines and α,β-unsaturated nitro compounds cycloaddition also occurs leading to unexpected pyrido[2,3-d]pyrimidines 5 and 9, respectively.
6-[(二甲基氨基)亚甲基]氨基-1,3-二甲基尿嘧啶1与非共轭亚胺发生正式的[4 + 2]环加成反应,产生嘧啶并[4,5-d]嘧啶3。当与共轭亚胺和α,β-不饱和硝基化合物反应时,也会发生环加成,分别得到意外的吡啶并[2,3-d]嘧啶5和9。