with either ethyl 3,3-diethoxy-2-methylpropionate (4) or methyl 3,3-dimethoxypropionate (5). The uracils (2a–d) were converted into cytosine analogues (3a–d)via intermediate 4-(1,2,4-triazol-1-yl) derivatives. (E)-5-(2-Bromovinyl)(36) and 5-vinyl (37) analogues of (2a) were prepared by palladium(II)-catalysed cross-coupling reactions on the 5-iodo derivative (32). The 5-fluoro-1-(hydroxyalkoxy)uracils
胸腺
嘧啶的1-(3-羟基丙
氧基),1- [3-羟基-2-(
羟甲基)丙
氧基],1-(2,3-二羟基丙
氧基)和1-(3,4-二羟基丁
氧基)衍
生物的合成(1a – d)和尿
嘧啶(2a – d)进行了描述。这些无环核苷是通过将适当官能化的
脲与
3,3-二乙氧基-2-甲基丙酸乙酯(4)或
3,3-二甲氧基丙酸甲
酯(5)环化而获得的。尿
嘧啶(2a – d)通过
中间体4-(1,
2,4-triazol-1-yl)衍
生物转化为
胞嘧啶类似物(3a – d)。(E)-5-(2-
溴乙烯基)(36)和(2a)的5-
乙烯基(37)类似物是通过
钯(II)在5-
碘衍
生物(32)上催化的交叉偶联反应制备的。5-
氟-1-(羟基烷
氧基)尿
嘧啶(41)和(42)通过将5-
氟-1-
羟基尿嘧啶与适当官能化的卤化物烷基化而获得。该系列无环核苷均未在
细胞培养物中的抗病毒测试中显示出活性。