Put some bitter apple spray on the bulldogs neck.
Often its so distasteful, the b will quit after one taste.
Some folks say this doesn't work for their b's, but it has worked for me.
You can find it in Petsmart or Pet Co.
You can use what Sharron suggested or use Tea Tree Oil. I can tell you from my experience the Basenji is just trying to play and get attention. When ours attempted to do this constantly I put my hand in his mouth and either put my thumb inside the bottom Jaw or finger up in the top jaw and held it there for a min and said no biting. This seems to work for us.