Studies on uracils: a facile one-pot synthesis of oxazino[4,5-d]-, pyrano[2,3-d]-, pyrido[2,3-d]- and pyrimido[4,5-d]pyrimidines using microwave irradiation in the solid state
作者:Ipsita Devi、Harsha N Borah、Pulak J Bhuyan
DOI:10.1016/j.tetlet.2004.01.094
日期:2004.3
N,N-Dimethyl-5-formylbarbituric acid 1 reacts with maleimide 2 and phenyl isocyanate/phenyl isothiocyanate 4 under microwave-assisted conditions in the solid phase to afford pyrano[2,3-d]pyrimidines 3 and oxazino[4,5-d]pyrimidines 5 in excellent yields. Under identical conditions, N,N-dimethyl-6-amino-5-formyluracil 6 reacts with 2 and 4 to give pyrido[2,3-d]pyrimidine derivative 7 and pyrimido[4,5-d]pyrimidines
N,N-二甲基-5-甲酰基巴比妥酸1在固相中微波辅助条件下与马来酰亚胺2和异氰酸苯基酯/异硫氰酸苯基酯4反应,得到吡喃并[2,3- d ]嘧啶3和恶嗪[4,5-]。d ]嘧啶5的收率极好。在相同条件下,N,N-二甲基-6-氨基-5-甲酰基尿嘧啶6与2和4反应生成吡啶并[2,3- d ]嘧啶衍生物7和嘧啶并[4,5- d ]嘧啶8高产。