 Due to these two different types of binding, small molecule Met inhibitors have been divided into two classes; class I (SU-11274-like) and class II (AM7-like).There is however another type of small-molecule inhibitors, which does not fit into either of the two classes; a non-competitive ATP inhibitor that binds in a different way to the other two.The small molecule inhibitors vary in selectivity, are either very specific or have a broad selectivity.