Antitumor agent-100 (compound A6) hydrochloride is an orally potent apoptosis inducer and molecular gel targeting PDE3A -SLFN12 ( IC 50 : 0.3 μM) with antitumor activity. Antitumor agent-100 hydrochloride binds to the PDE3A enzyme pocket to recruit and stabilize SLFN12, thereby preventing protein translation and leading to apoptosis.