Methylated DNA: The influence of 7-deaza-7-methylguanine on the structure and stability of oligonucleotides
作者:Frank Seela、Yaoming Chen
DOI:10.1002/hlca.19970800406
日期:1997.6.30
The 7-deaza-2′-deoxy-7-methylguanosine (2b) [9], which is the glycosylic-bond-stable, noncharged analogue of 2′-deoxy-7-methylguanosine (1b), was incorporated in DNA by solid-phase synthesis. As building blocks, the protected phosphonatc 3a and the phosphoramidite 3b were prepared. The 7-methyl group of 2b stabilizes the B-DNA duplex compared to 7-deaza-2′-deoxyguanosine but does not induce a B-Z transition
通过固体将7-deaza-2'-deoxy-7-甲基鸟苷(2b)[9b]糖基键合稳定的,不带电荷的2'-deoxy-7-甲基鸟苷(1b)类似物掺入DNA中。相合成。作为构件,制备了被保护的膦酸酯3a和亚磷酰胺3b。与7-deaza-2'-deoxyguanosine相比,2b的7-甲基可稳定B-DNA双链体,但不会诱导BZ过渡,如从化合物1b所知。7-脱氮基-7-甲基鸟嘌呤部分的稳定作用是序列依赖性的,并且最邻近的影响不同于7-脱氮基鸟嘌呤的影响。2b的寡核苷酸显示出S形熔化,表明高度有序的单链结构。通常,含有2b的寡核苷酸对小牛脾脏磷酸二酯酶(CS-PDE,5'3'核酸外切酶)水解非常稳定,而蛇毒磷酸二酯酶(SV-PDE,3'5'核酸外切酶)的磷酸二酯水解仅轻微减少。