摘要 |
This invention is directed to a compound of Formula I;;or a pharmaceutically acceptable salt thereof, wherein R1, R2, R3, R4 and X are as defined herein. The compounds of Formula I are useful as receptor tyrosine kinase (RTK) inhibitors and can be used to treat such diseases as cancer, blood vessel proliferative disorders, fibrotic disorders, mesangial cell proliferative disorders and metabolic diseases. |