6-Chloroxanthosine 1, when activated towards nucleophilic displacement at the 6-C position by conversion into the corresponding 3-N-(2,4- dinitrophenyl) derivative 4, reacted with aq. 15NH3 to afford [6-15N]- isoguanosine 3b in 81% overall yield. Catalytic hydrogenation (Pd/C) of 1 led in 60 % yield to isoinosine 8; alternatively, this could be obtained in 88 % overall yield through alkaline hydrolysis of triphenylphosphonium salt 6, synthesized from 1 by reaction with PPh3. The reactivity of 1 was further explored by treating it with primary and secondary amines: the 6-N propylamino and the 6-N piperidinyl derivatives (5a and 5b, respectively) could thus both be prepared in more than 90 % yield.
6-Chloroxanthosine, a useful intermediate for the efficient syntheses of [6-15N]-isoguanosine, isoinosine and other purine nucleoside analogues
MESSERE, Anna;
1997
Abstract
6-Chloroxanthosine 1, when activated towards nucleophilic displacement at the 6-C position by conversion into the corresponding 3-N-(2,4- dinitrophenyl) derivative 4, reacted with aq. 15NH3 to afford [6-15N]- isoguanosine 3b in 81% overall yield. Catalytic hydrogenation (Pd/C) of 1 led in 60 % yield to isoinosine 8; alternatively, this could be obtained in 88 % overall yield through alkaline hydrolysis of triphenylphosphonium salt 6, synthesized from 1 by reaction with PPh3. The reactivity of 1 was further explored by treating it with primary and secondary amines: the 6-N propylamino and the 6-N piperidinyl derivatives (5a and 5b, respectively) could thus both be prepared in more than 90 % yield.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
