A simple synthesis of 2,4-dimethoxy-5-(3-oxoalkynyl)pyrimidines from the readily available 5-ethynyl-2,4-dimethoxypyrimidine is described. The sequence proceeds via an ethynylboron intermediate which is acylated with carboxylic anhydrides. The 5-(3-oxo-1-alkynyl) products are hydrogenated to the saturated analogs and these are O-dealkylated with chlorotrimethylsilane/sodium iodide to give 5-(3-oxoalkyl)uracils, e.g., 5-(3-oxobutyl)-, 5-(3-oxopentyl)-, and 5-(3-oxohexyl)uracil. These compounds and the nucleosides derived therefrom are of interest as anticancer and antiviral agents.
描述了从容易获得的 5-
乙炔基-2,4-二
甲氧基嘧啶中简单合成 2,4-二甲氧基-5-(3-氧代炔基)
嘧啶。该序列通过用
羧酸酐酰化的
乙炔基
硼中间体进行。 5-(3-氧代-1-炔基)产物被氢化成饱和类似物,并用
氯三甲基
硅烷/
碘化钠进行O-脱烷基化,得到5-(3-氧代烷基)尿
嘧啶,例如5-(3-氧代丁基) -、5-(3-氧代戊基)-和5-(3-氧代己基)尿
嘧啶。这些化合物和由其衍生的核苷作为抗癌剂和抗病毒剂受到关注。