Divergent synthesis of 2,6-diaryl-substituted 5,7,8-trimethyl-1,4-benzoxazines via microwave-promoted palladium-catalyzed Suzuki–Miyaura cross coupling and biological evaluation

An efficient palladium-catalyzed Suzuki–Miyaura cross-coupling protocol effected in a mixture of DME/water (2:1) enables the reaction of sterically hindered and electron rich 6-chloro or 6-bromo-1,4-benzoxazines(ones) with a variety of aryl, vinyl or alkylboronic acids. Coupling is effected with catalyst loading of 5 mol % using sealed-vessel microwave processing. The resulting compounds exhibit potent activity against Toxoplasma gondii tachyzoite proliferation.