So the intercession of the intercessors will be of no use to them.
The intercession of the intercessors will never help them.
The intercession of their intercessors shall not benefit them
So the intercession of intercessors will not avail them
So the mediators' mediation does not benefit them
God will not accept any intercession for such sinners
So the intercession of the intercessors will not benefit them. (The disbelievers will not have any intercessor.
So the intercession of intercessors will not avail them
So (now) the intercession of the intercessors will not be of any benefit to them
That is why the intercession of the intercessors will be of no avail to them
So no intercession of intercessors will be of any use to them