Facile Regioselective Synthesis of Symmetrical Trans Bis-Pyrrolo Isoxazoles Cycloadducts from Glyoxal Bis-Nitrones

Abstract

In present study, bis-nitrones of glyoxal were synthesized initially, and subjected to cycloaddition reaction with N -substituted maleimides in toluene medium to afford a series of new symmetric bis-pyrrolo isoxazoles cycloadducts in excellent yields and shorter reaction time. The reaction afforded a single regio-isomer of symmetric bis-pyrrolo isoxazoles as confirmed by 1 H-NMR spectral analysis, in a shorter reaction period of 15-20 minutes. Thus, present protocol presents a facile and regioselective synthesis of bis-pyrrolo isoxazoles.