ABSTRACT
As mentioned above, the target sequence had to be assembled by ligation from an 8mer RNA sequence S3 and a phosphorylated derivative o f a lOmer RNA sequence containing wyosine at the 5'-end (S4) (Fig. 5C). The ligation was carried out using T4-DNA ligase and a so called splint DNA,47 which is complementary to the target RNA sequence. In the present case, a phosphoramid ite based on 1,3-propandiol was employed to incorporate an abasic site opposite to the sterically demanding wyosine into the splint S6. The ligation product S3 was obtained in 90% and, after HPLC purification, its correct chemical composition was confirmed by ESI-MS.
