The title 1,2-bis(purin-6-yl)acetylenes, -diacetylenes, -ethylenes and -ethanes were prepared as covalent base-pair analogues starting from 6-ethynylpurines and 6-iodopurines by the Sonogashira cross-coupling or oxidative alkyne-dimerization reactions followed by hydrogenations. 6-[(1,3-Dimethyluracil-5-yl)ethynyl]purine (11) was prepared analogously and hydrogenated to the corresponding purine-pyrimidine conjugates linked via vinylene and ethylene linkers. Unlike the cytostatic bis(purin-6-yl)acetylenes and -diacetylenes, the purine-pyrimidine conjugates were inactive. Crystal structures of bis(purin-6-yl)acetylene 6a, -diacetylene 8a and -ethane 5a were determined by single-crystal X-ray diffraction.
1,2-双(
嘌呤-6-基)
乙炔,-二炔,-
乙烯和-
乙烷作为共价碱对类似物从6-
乙炔基
嘌呤和
6-碘嘌呤出发,通过Sonogashira交叉偶联或氧化炔基二聚反应制备,随后进行氢化反应。类似地制备了6-[(1,3-二甲基尿
嘧啶-5-基)
乙炔基]
嘌呤(11),并将其氢化为相应的
嘌呤-
嘧啶共轭物,通过
乙烯和
乙烷连接器连接。与细胞静止作用的双(
嘌呤-6-基)
乙炔和-二炔不同,
嘌呤-
嘧啶共轭物无活性。通过单晶X射线衍射测定了双(
嘌呤-6-基)
乙炔6a,-二炔8a和-
乙烷5a的晶体结构。