Spirocyclic azetidines for drug discovery: Novel Boc-protected 7'H-spiro[azetidine-3,5'-furo[3,4-d ]pyrimidines]

A novel spirocyclic scaffold of 7'H-spiro[azetidine-3,5'-furo[3,4-d]pyrimidine] chemotype was synthesized in N-Boc-protected form. However, the scaffold was revealed to be unstable to storage when deprotected. The solution was found in the brief removal of the Boc protecting group and rapid acylation of the liberated NH-azetidine with a carboxylic acid imidazolide.