The invention provides certain thiazole-substituted aminopyrimidine compounds of the Formula (I) (I), or pharmaceutically acceptable salts thereof, wherein R1, R2, R3, R5, R6, and the subscripts r, s, and t are as defined herein. The invention also provides pharmaceutical compositions comprising such compounds, and methods of using the compounds for treating diseases or conditions mediated by Spleen Tyrosine Kinase (Syk).