Thanks for your replies BFG and Mizuno!
I was looking for GIG (Rio de Janeiro Intl.)- TEB.
Great Circle it's 4,177nm / Airways computed it's 4350 nm (~10:20 flying LRC).
Taking into account the usual early descents for the arrival, I think it's quite on the limit...
So, according to (unrealistic) Dassault, the aircraft is 4,750 nm with winglets installed and a normal BOW. How come their advertisement is SOOOO stretched???