The design, synthesis and antileukemic activity of 5-alkynel-1-β-D-ribofuranosylimidazole-4-carboxamides (6) are described. The cross-coupling reaction of 5-iodo-1-(2, 3, 5-tri-O-acetyl-β-D-ribofuranosyl)imidazole-4-carboxamide (8) with various terminal alkynes in the persence of bis(benzonitrile)palladium dichloride and triethylamine in acetonitrile gave 5-alkylnyl derivatives (9) in high yields. Coupling of 8 with (trimethylsilyl)acetylene gave hte undesired dimer (10). Instead of (trimethylsilyl)acetylene, treatment of trimethyl[(tributyl-satannyl)ethynyl]silane with 8 in the absence of triethylamine produced the desired 5-[2-(trimethylsilyl)ethynyl] derivative (9f) in 77% yield. Deblocking of these nucleosides (9) gave the target nucleosides (6a-f). Among them, 5-ethynyl-1-β-D-ribofuranosylimidazole-4-carboxyamide (6f) is the most potent inhibitor of the growth of murine L1210 cells in vitro (IC50=0.18 μg/ml).
描述了 5-炔基-1-β-D-
呋喃核糖基
咪唑-4-甲酰胺 (6) 的设计、合成和抗白血病活性。 5-
碘-1-(2,3,5-三-O-乙酰基-β-D-
呋喃核糖基)
咪唑-4-甲酰胺(8)与各种末端
炔烃在双(
苯甲腈)存在下的交叉偶联反应)二
氯化钯和
三乙胺在
乙腈中以高产率得到5-烷基衍
生物(9)。 8与(三甲基甲
硅烷基)
乙炔偶联得到不需要的二聚体(10)。在不存在
三乙胺的情况下,用8代替(三甲基甲
硅烷基)
乙炔处理三甲基[(三丁基-饱和烷基)
乙炔基]
硅烷,产生所需的5-[2-(三甲基甲
硅烷基)
乙炔基]衍
生物(9f),收率77%。这些核苷 (9) 的解封闭得到目标核苷 (6a-f)。其中,5-
乙炔基-1-β-D-核
呋喃基
咪唑-4-羧酰胺(6f)是体外小鼠L1210细胞生长最有效的
抑制剂(IC50=0.18 μg/ml)。