Collins Russian Dictionary 2nd Edition © HarperCollins Publishers 2000, 1997:
stupefy [ˈstjuːpɪfaɪ] vt (tire) приводи́ть*(привести́*perf) в отупе́ние (fig) изумля́ть (изуми́ть*perf)
* is used to mark translations which have irregular inflections. The Russian-English side of the dictionary gives inflectional information.