Design and Synthesis of Some New 1,4-Benzoxazine-Isoxazole Hybrids as In Vitro Anticancer Agents

Synthesis of twelve novel regioselective 1,4-benzoxazine-isoxazole hybrids as in vitro anticancer agents via Cu(I) catalyzed one-pot reaction of various terminal alkynes with 3-(3-oxo-2H-benzo[b][1,4]oxazin-4(3H)-yl)propanal in benign aqueous t-butanol at room temperature is presented herein. Five products have demonstrated promising activity, among those the compound 6f demonstrates outstanding activity towards PC3, A549, MCF-7, and HeLa with IC50 values of 2.61, 3.34, 2.74, and 7.04 μM respectively.