Collins Russian Dictionary 2nd Edition © HarperCollins Publishers 2000, 1997:
avail [əˈveɪl] vt
to avail o.s. of воспо́льзоваться (perf) +instr
n
to no avail напра́сно
* is used to mark translations which have irregular inflections. The Russian-English side of the dictionary gives inflectional information.