Asymmetric synthesis of 2'-phosphonomethyl(3',4'-dihydroxybutyl)cytosine and -guanine nucleotides

Article abstract of DOI:10.1016/S0957-4166(97)00258-9

The synthesis of 2'-phosphonomethyl(3',4'-dihydroxylbutyl) nucleotides of cytosine and guanine 13 and 15 possessing the 2'S,3'S absolute configuration was readily accomplished in eleven and ten steps respectively from L-ascorbic acid via the protected tetrols 9 and 8. Alcohol 8 undergoes efficiently a regiospecific Mitsunobu coupling with 6-chloro-2-aminopurine to furnish the N-9 isomer which was further transformed to 15.