Cleavage / Deprotection of nucleobase moieties

The crude oligonucleotide obtained by solid-phase synthesis remains bound to the solid support. After synthesis, it is cleavaged from the solid support by ester hydrosis with a base such as concentrated ammonia water. At the same time, the protecting group introduced into the amino group of the nucleobase moiety is removed under basic conditions. Instead of concentrated ammonia water, methylamine solution, AMA solution (a mixture of concentrated ammonia water and methylamine solution), or potassium carbonate/methanol solution may be used for this reaction depending on the type of protecting group.