trifluoro-methanesulfonic acid 1-(1-ethyl-propyl)-3,6-dimethyl-1H-pyrazolo[3,4-b]pyrazin-5-yl ester 、
1-(1-ethyl-propyl)-6-methoxy-3-methyl-1H-pyrazolo[3,4-b]pyrazin-5-ol 、
三氟甲磺酸酐 在
silica gel 作用下,
以
三乙胺 为溶剂,
以gives trifluoro-methanesulfonic acid 1-(1-ethyl-propyl)-6-methoxy-3-methyl-1H-pyrazolo[3,4-b]pyrazin-5-yl ester的产率得到trifluoro-methanesulfonic acid 1-(1-ethyl-propyl)-6-methoxy-3-methyl-1H-pyrazolo[3,4-b]pyrazin-5-yl ester