The present teachings provide a compound represented by structural formula (II-A0), or a pharmaceutically acceptable salt thereof. R1 is –NHRb1, where Rb1 is alkyl which may be optionally substituted with one or more groups as defined herein. R2 is optionally substituted heterocycloalkyl, heteroaryl, optionally substituted aryloxy, optionally substituted heteroaryloxy, optionally substituted heterocyclyloxy or substituted amino (and wherein the substituents are as defined herein). R4 is chloro or methyl. Rd is cyclopropyl. Specific compounds include N-cyclopropyl-4-(7-(((trans-3-hydroxy-3-methylcyclobutyl)methyl)amino)-5-(pyridin-3-yloxy)pyrazolo[1,5-a]pyrimidin-3-yl)-2-methylbenzamide (CFI-402257) and N-cyclopropyl-4-(7-((cyclopropylmethyl)amino)-5-(((1S,2R)-2-hydroxycyclohexyl)amino)pyrazolo[1,5-a]pyrimidin-3-yl)-2-methylbenzamide. Also described are pharmaceutical compositions and uses thereof, such as for the inhibitors of tyrosine threonine kinase (TTK) and for the treatment of cancers such as pancreatic cancer, prostate cancer, lung cancer, melanoma, breast cancer, colon cancer, or ovarian cancer.
