Abstract
2-Formyl-d-xylal 2a and 2-formyl-l-arabinal 2b were reacted with hydrazines to furnish the 4-[1,2-bis(benzyloxy)-3-hydroxypropyl]-1H-pyrazoles 3a-f. Treatment of 2b with 5(3)-aminopyrazole-4-carboxylates 5a-d in the presence of NaH afforded the ethyl 6-[1,2-bis(benzyloxy)-3-hydroxypropyl]pyrazolo[1,5-a]pyrimidine-3-carboxylates 6a-d. Ring transformation of 2a,b with 2-aminobenzimidazole yielded the 3-[1,2-bis(benzyloxy)-3-hydroxypropyl]benzo[4,5]imidazo[1,2-a]pyrimidines 7a,b.
Key words
carbohydrates - heterocycles - nucleosides - ring transformation
