CHEMICAL-ENZYMATIC SYNTHESIS OF 3'-AMINO-2',3'-DIDEOXY-BETA-D-RIBOFURANOSIDES OF NATURAL HETEROCYCLIC BASES AND THEIR 5'-MONOPHOSPHATES

Treatment of O-2,3'-anhydro-5'-O-trityl derivatives of thymidine (1) a nd 2'-deoxyuridine (2) with lithium azide in dimethylformamide at 150 degrees C resulted in the formation of the corresponding isomeric ido- 2',3'-dideoxy-5'-O-trityl-beta-D-ribofuranosyl N1- (the major products ) and N-3-nucleosides (3/4 and 5/6). 3'-Amino-2',3'-dideoxy-beta-D-rib ofuranosides of thymidine Thd(3'NH2), uridine dUrd(3'NH2), and cyt idine dCyd(3'NH2) were synthesized from the corresponding 3'-azido d erivatives. The Thd(3'NH2) and dUrd(3'NH2) were used as donors of carb ohydrate moiety in the reaction of enzymatic transglycosylation of ade nine and guanine to afford dAdo(3'NH2) and dGuo(3'NH2). The substrate activity of dN(3'NH2) vs. nucleoside phosphotransferase of the whole c ells of Erwinia herbicola was studied.