首次观察到 DNA 内部的皮秒和纳秒动力学,因为特殊设计的碱基对类似物的荧光发生动态斯托克斯位移。最近合成的香豆素 C-核糖苷已被整合到寡核苷酸中,以取代正常的嘌呤·嘧啶碱基对。该探头的动态斯托克斯位移发生在接近 300 ps 和 13 ns 的元件上。这些时间对于溶剂松弛或 DNA 框架的简单振动运动来说太长了。它们意味着 DNA 的内部是一个独特的动态环境,不同于流体或分子晶体。
Coumarin base-pair replacement as a fluorescent probe of ultrafast DNA dynamics
摘要:
The design and synthesis of a novel coumarin C-riboside are described, and is based on the well-known photoprobe Coumarin 102. A diastereofacial selective Heck coupling between a furanoid glycal and a coumarin triflate provided a method for glycoside formation. The coumarin C-glycoside was incorporated synthetically into DNA oligomers, and was used to probe ultrafast dynamics of duplex DNA using time-resolved Stokes shift methods. (c) 2007 Published by Elsevier Ltd.