The original plan was just to ammend the articles of confederation, but there was just too much wrong with it, because it gave too much Federal power. The Federalist wanted a strong central government, and the anti Federalists wanted more power in the states.
The biggest compromise that was made would be the Federalists including agreeing to include a bill of rights in the Constitution.
This was the main thing the anti Federalist wanted in the Constitution, it was the thing that sold them.
