B or 7-chloro-3-(2, 3, 5-tri-O-acetyl-~-~-ribofuranosyl) pyrazolo [4, 3-d] pyrimidine (10) and following the similar sequence of reactions, we obtained compound 13. The in vitro antiviral studies of these carbamoyl and certain related nucleosides indicated 7a to be a potent antiviral agent against vaccinia virus, whereas 13 was moderately active. 4-Chloro-7-~-~- ribofuranosylpyrrolo [2, 3-d] pyrimidine was found to be one of the most active compounds ...
![[3,4-diacetyloxy-5-(5-chloro-2,4,8,9-tetrazabicyclo[4.3.0]nona-2,4,7,10-tetraen-9-yl)oxolan-2-yl]methyl acetate Structure](https://image.chemsrc.com/caspic/011/78586-33-1.png)
![1H-Pyrazolo[3,4-d]pyrimidine,4-(methylthio)-1-(2,3,5-tri-O-acetyl-b-D-ribofuranosyl)- Structure](https://image.chemsrc.com/caspic/019/60355-66-0.png)