Solid phase synthesis of mRNA by the phosphoramidite approach using 2'-O-1-(2-chloroethoxy)ethyl protection and its stability in E. coli system.

The decaoligoribonucleotides containing initiation codon AUG of the phage O beta-A protein mRNA were synthesized on a solid phase by the phosphoramidite approach using 2'-O-1-(2-chloroethoxy)ethyl (Cee) protection. The Cee group is completely stable under the acidic conditions required to remove the 5'-terminal protecting groups in oligoribonucleotide synthesis on a solid support, and yet is easily removable at pH 2.0 for the final unblocking step. Stabilization of the synthetic mRNA to in the cell-free translation system from E. coli A19 was measured. It was found that the oligomers with selected 2'-O-methylation were degraded completely in the translation system.