A series of Δ2-isoxazoline constrained analogues of procaine/procainamide (7a–k and 8a– k) were prepared and their inhibitory activity against DNA methyltransferase 1 (DNMT1) was tested. Among them, derivative 7b is far more potent in vitro (IC50= 150 μM) than other non- nucleoside inhibitors and also exhibits a strong and dose-dependent antiproliferative effect against HCT116 human colon carcinoma cells. The binding mode of 7b with the enzyme ...