Extended R1 analogs of AT7519. A) CDK14 IC50s were
measured using a LanthaScreen binding assay. IC50s were calculated as
the average of three replicates, and are reported ± the standard errorB)
Antiproliferative activity against the HCT116 cell line was measured using a
CellTiter-Glo assay. IC50s were calculated as the average of three
replicates, and are reported ± the standard error. –R is used to
denote reversible control compounds (without an alkene group).