Two routes for the synthesis of 6-substituted 8-azaguanosine analogues are described. 2, 5, 6-Triamino-4 (3H)-pyrimidinethione (1) was converted by methylation, nitrosation, and acetylation to N-acetyl-7-(methylthio)-3H-1, 2, 3-triazolo [4, 5-d] pyrimidin-5-amine (5). The reaction of 5 with 2, 3, 5-tri-O-acetyl-D-ribofuranosyl chloride gave a mixture of the 7-, 8-, and 9-(2, 3, 5-tri-0-acetyl-@-~-ribofuranosyl)-8-azapurines 4a-c which was converted to 8- ...
![[1,2,3]Thiadiazolo[5,4-d]pyrimidine-5,7-diamine Structure](https://image.chemsrc.com/caspic/167/59886-09-8.png)
![3-amino-9-[3,4-dihydroxy-5-(hydroxymethyl)oxolan-2-yl]-2,4,7,8,9-pentazabicyclo[4.3.0]nona-1,3,6-triene-5-thione Structure](https://image.chemsrc.com/caspic/395/59886-03-2.png)
![[1,2,3]Thiadiazolo[5,4-d]pyrimidine-5,7-diamine, N7-b-D-ribofuranosyl- (9CI) Structure](https://image.chemsrc.com/caspic/243/59886-07-6.png)