A series of pyrazolopyrimidinone analogs were synthetized [142] and, in 2016, Matheson and collaborators reported a compound (CJM-061) that showed the same Wee1 inhibitory efficacy of AZD1775, but had reduced single-agent cytotoxicity in medulloblastoma cells [133]. Here, WEE1 is linked to medulloblastoma.