| abstract |
(57) [Summary] The present invention provides a compound represented by the formula: And their pharmaceutically acceptable salts. In formula (I) and in the description, the symbols have the following meanings: R 1 and R 2 are independently hydrogen, fluorine or alkyl; R 3 is aryl or heteroaryl. The compounds of formula (I) are protein kinase inhibitors and are effective in treating and preventing proliferative disorders such as cancer, inflammation and arthritis. |