The synthesis of adenophostin A (2) and two analogues [etheno adenophostin (4) and 8-bromo adenophostin (5)] modified at the adenine moiety, is reported. A combination of NMR analysis and molecular modelling was used to compare their structures in solution and determined that they all adopt very similar conformations. The analogues were tested for their ability to mobilise Ca2+ from DT40 cells expressing recombinant Type 1 rat Ins(1,4,5)P3R which reveals etheno adenophostin as a high affinity fluorescent probe of the Ins(1,4,5)P3R. 8-Bromo adenophostin was only slightly less potent. The biological results support our current hypothesis regarding the binding mode of adenophostin A at the Ins(1,4,5)P3R, i. e. that a cation–π interaction between the base moiety and Arg 504 of the receptor in combination with H-bonding may be responsible for the high potency of adenophostin A relative to Ins(1,4,5)P3.
报告了
腺苷 A(2)和两种在
腺嘌呤分子上进行了修饰的类似物[
乙烯腺苷(4)和 8-
溴腺苷(5)]的合成过程。通过核磁共振分析和分子建模相结合的方法来比较它们在溶液中的结构,结果表明它们都采用了非常相似的构象。对这些类似物从表达
重组 1 型大鼠 Ins(1,4,5)P3R 的 DT40 细胞中调动 Ca2+ 的能力进行了测试,结果显示
乙烯腺苷是 Ins(1,4,5)P3R 的高亲和力荧光探针。8-Bromo adenophostin 的效力略低。
生物学结果支持了我们目前关于
腺苷 A 与 Ins(1,4,5)P3R 结合模式的假设,即碱基分子与受体 Arg 504 之间的阳离子-π 相互作用与 H 键结合可能是
腺苷 A 相对于 Ins(1,4,5)P3 具有高效力的原因。