Sorry, but no. TNT is pretty much as far as you can get - there simply isn't enough room to squeeze in any more NO2 groups. Also, it takes seriously extreme conditions to force that third NO2 onto the ring. If you tried to put any more on, you'd be putting so much energy into the reaction that the TNT itself would decompose, to put it mildly.
David Shaw
TNT on the other hand. In theory, since the core of toluene is a benzene ring,
you can attach up to 6 NO2 groups. Of course these are unstable, and adding more makes the explosive more powerful. So QNT would be really scary stuff.