I'm not aware of any way of doing this unless you have access to create DB links and synonyms on the objects you want to access on B.
Having said that, I've not tried that either so there may be security concerns with it.
But the theory goes:
A
wants to access TABLE_1
on C
, via B
- Create a link from
B
toC
- Create synonym on
B
-C_TABLE_1
forTABLE_1@C
- Create a link from
A
toB
- Access via
C_TABLE_1@B
Alternatively could you create a DB link direct from A to C?