摘要:
3,5'-Di-O-mesylthymidine 4a (DMST) on reaction with secondary amines undergoes hitherto unknown ''one-pot-two-steps'' transformation to produce 2,3'-O-anhydro-5'-deoxy-5'-alkylaminothymidines 5a-h. Most of the amines used, irrespective of their basicities showed remarkable selectivity towards the 5'-substitution over the 2,3'-O-anhydro ring formation. Compounds 5a-h could be used as intermediates for the synthesis of a variety of 3,5'-dideoxy-3'-substituted-5'-alkylaminothymidines of the type 9, 10a-b, 11.