The present invention relates to compounds of the general formula (I) wherein R1, R2 and R3 are as defined herein, which can act as inhibitors of protein kinases, specially the Fms-like tyrosine kinase 3 (FLT3). The invention also relates to the use of the compounds in therapy, pharmaceutical compositions comprising the compounds and the use of the compounds for the preparation of a medicament for the prophylaxis and treatment of hematological malignancies, such as AML, MLL, T-ALL, B-ALL and CMML, myeloproliferative disorders, other proliferative disorders like cancer, autoimmune disorders and skin disorders like psoriasis and atopic dermatitis.