[1,3]oxazines: green synthesis by sonication using a magnetically-separable basic nano-catalyst and investigation of its activity against the toxic effect of a pesticide on the morphology of blood cells

The demand for a cleaner environment has led chemists to develop greener protocols, notably by using catalysts. Encapsulation of an active substance on a solid support makes the process of separation of the catalyst much simpler, thereby generating minimal waste. We report herein the preparation of a novel basic catalyst, 3-methylaminopropyl-functionalized Fe3O4 nanoparticles (Fe3O4@MAP nanoparticles), which catalyzes the one-pot synthesis of [1,3]oxazine derivatives under ultrasonic conditions. Advantages include mild reaction condition, easy catalyst recovery and recyclability, shorter reaction time and use of green solvents. We also found that one derivative, 2-(4-methoxyphenyl)-2,3-dihydro-1H-naphtho[1,2-e][1,3]oxazine, suppresses the toxic effect caused by the chlorpyrifos pesticide on the blood cells of Polypedates teraiensis tadpoles.