The present invention relates to nitrogen-containing heterocyclic compounds and pharmaceutically acceptable salts thereof which have inhibitory activity on the phosphorylation of kinases, which inhibits the activity of such kinases. The invention is also related to a method of inhibiting kinases and treating disease states in a mammal by inhibiting the phosphorylation of kinases. In a particular aspect the present invention provides nitrogen-containing heterocyclic compounds and pharmaceutically acceptable salts thereof which inhibit phosphorylation of a of a PDGF receptor to hinder abnormal cell growth and cell wandering, and a method for preventing or treating cell-proliferative diseases such as arteriosclerosis, vascular reobstruction, cancer and glomerulosclerosis.