[A facile synthesis of adenosine 3', 5'-cyclic methylphosphonate and methylphosphonothioate]

A facile synthesis of adenosine 3', 5'-cyclic methylphosphonate (1) and 3', 5'-cyclic methylphosphonothioate (2) was accomplished by treatment of 2'-protected adenosine with O,O-bis (1-benzotriazolyl) methylphosphonate or O,O-bis (1-benzotriazolyl) methylphosphonothioate under mild conditions, respectively. The ability of the compounds to inhibit DNA synthesis in mice hepatoma was tested. A pair of diasteromers of 2'-protected (1) was separated and the configuration at the phosphorus atom was identified.