To thoroughly avoid the lone pair repulsion, we shifted this N atom to the metaor paraposition, and as expected, the resulting 7c and 7d displayed a single-digit nanomolar IC50 against HPK1. As representatives of five-membered rings, various pyrazolyl groups were also introduced. Among them, N-methylpyrazolyl were well tolerated (7e and 7f), but prolonging the N-alkyl chains by one carbon unit could slightly erode the potencies (7g and 7h). Furthermore, adding a methyl group to certain positions of the pyrazole ring could bring detrimental effects (7j vs 7e, 7k vs 7f), and the activity was completely lost when the pyrazole ring was dimethylated (7l), which could be imputed to steric hindrances of the methyl groups that impeded the pyrazole ring from adopting the optimal conformation. Interestingly, during the subsequent examination on the more active 1H-pyrazol-4-yl group, we found that attaching bulkier alkyl groups to the pyrazole N atom could recover the strong inhibitory effects (7m and 7n), especially the cyclopropyl group (7m, IC50 = 5.7 nM).