A novel pyrimidine nucleoside derivative of formula (1) or (2) and a salt thereof, wherein R¹ represents amino which may be substituted with hydroxy or acyl; R² represents hydrogen or C₁ to C₄ alkyl; R³ represents hydrogen or hydroxy; and R⁴ and R⁵ represent each hydrogen or they may be combined together to represent -R⁶R6'Si-O-SiR⁷R7'-, wherein R⁶, R6', R⁷ and R7' each represents lower alkyl. This compound has an excellent antitumor effect or serves as a useful intermediate for the synthesis of antitumor drugs.
式(1)或(2)的新型
嘧啶核苷衍
生物及其盐,其中 R¹ 代表可被羟基或酰基取代的
氨基;R² 代表氢或 C₁ 至 C₄ 烷基;R³ 代表氢或羟基;R⁴ 和 R⁵ 分别代表氢或它们可以组合在一起代表 -R⁶R6'Si-O-SiR⁷R7'-,其中 R⁶、R6'、R⁷ 和 R7'分别代表低级烷基。这种化合物具有极佳的抗肿瘤效果,或可作为合成
抗肿瘤药物的有用中间体。