title: Reaction mechanism for the diastereocontrolled synthesis of phosphorothioate DNA by the oxazaphospholidine approach.
abstract: Reaction mechanisms for the diastereoselective synthesis of deoxyribonucleoside 3'-cyclic phosphoramidites as well as dinucleoside phosphite intermediates by the oxazaphospholidine approach were analyzed by means of ab initio molecular orbital calculations at the HF/6-31G* level. These reactions are essential for the diastereoselective synthesis of phsophorothioate DNA.
authors.affiliation: Department of Integrated Biosciences, Graduate School of Fronties Sciences, The University of Tokyo, Kashiwa, Japan. wada@k.u.tokyo.ac.jp
authors.forename: Takeshi
authors.initials: T
authors.lastname: Wada
authors.forename: Natsuhisa
authors.initials: N
authors.lastname: Oka
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Saigo
mesh_terms: D004247:DNA / Q000138:chemical synthesis*; D003854:Deoxyribonucleotides / Q000138:chemical synthesis / Q000737:chemistry; D008958:Models, Molecular; D008968:Molecular Conformation; D010710:Phosphates; D013237:Stereoisomerism
chemical_list: D003854:Deoxyribonucleotides; D010710:Phosphates; C083120:phosphorodithioic acid; D004247:DNA