Abstract A new efficient synthesis of 2,5,6-trisubstituted oxazolo[5,4-d]pyrimidi-7(6H)-ones by consecutive aza-Wittig reaction was developed. The sequential three-component reaction of oxazolyliminophosphorane 4, isocyanates and amines produced 2,5,6-trisubstituted oxazolo[5,4-d]pyrimidi-7(6H)-ones 7 in good overall yields in the presence of catalytic amount of EtONa.

中文翻译：

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通过恶唑基亚氨基膦环烷新型高效合成2,5,6-三取代的恶唑并[5,4-d]嘧啶-7（6H）-

摘要研究了通过连续的氮杂-维蒂希反应连续合成2,5,6-三取代的恶唑并[5,4-d]嘧啶-7（6H）-的新方法。在催化量的EtONa存在下，恶唑基亚氨次膦4，异氰酸酯和胺的顺序三组分反应以良好的总收率产生了2,5,6-三取代的恶唑并[5,4-d] pyrimidi-7（6H）-ones 7。 。