An approach to alicyclic ring-fused xanthines

A convenient three-step approach to the synthesis of five to eight-membered alicyclic ring-fused xanthines was developed. The method included reaction of lactim or thiolactim ethers with 6-aminouracils, followed by bromination and copper-catalyzed arylation. The procedure allowed preparation of the title compounds in 21–36% overall yields.

Liubchak K.; Tolmachev A.; Grygorenko O. O.; Nazarenko K.
Tetrahedron 2012, 68 (41), 8564-8571
DOI: 10.1016/j.tet.2012.08.014