Uridine 5'-monoselenoacetals as substrates for diastereoselective homolytic C-C bond formation

Article abstract of DOI:10.1016/0040-4020(96)00483-8

Uridine 5'-monoselenoacetals prepared by the seleno-Pummere reaction of 5'-deoxy-5'-phenylselenouridines were used as substrates for radical-mediated reactions with allyltributyltin. The reaction of the 2',3'-O-isopropylidene derivative gave cyclized products, 5-allyl-6-5'-cyclonucleosides, whereas those of the 2',3'-bis-O-(tert-butyldimethylsilyl derivatives underwent the C-C bond formation at the 5'-position to give (5'S)- and (5'R)-isomers. The stereochemical outcome of both types of reactions is discussed. The use of radical acceptors other than allyltributyltin was also examined.