Why ampere is base unit if it is derived from charge?

The ampere is the SI Base Unit or electric current. It is NOT derived from the charge (coulomb) but from the force resulting from its magnetic effect. The ampere is defined in terms of the force between two, parallel, current-carrying conductors due to the interaction of their magnetic fields. The coulomb, on the other hand, is an SI Derived Unit, based on the ampere and the second.