The four possible 3'-uracil-1-yl and 3'-thymin-1-yl derivatives of 3'-
deoxythymidine and the four analogous derivatives of 2'-deoxyuridine h
ave been synthesised from thymidine and uridine, respectively. Advanta
ges of the 2-(methoxycarbonyl)vinyl group to prevent the formation of
anhydronucleosides and of SnCl2/PhSH/Et3N in relation to H-2/Pd for th
e reduction of most azido groups are disclosed. (C) 1998 Elsevier Scie
nce Ltd. All rights reserved.