Solid-phase synthesis of RNA via a silyl-protecting-group strategy

Ribonucleoside phosphoramidites have been prepared of which the exocyclic amino functions and 2′-hydroxyl functions are protected with 2-[(tert-butyldiphenylsiloxy)methyl]benzoyl groups and tert-butyldimethylsilyl groups, respectively. The N-SiOMB/O-TBDMS-blocked nucleosides proved to be suitable building units in a solid-phase synthesis of the RNA-fragment 5′-AGAGUACCU-3′ via a phosphite triester approach.