[3+2] Cycloaddition Between Cyclic Diaryl λ3-Bromanes and Nitrones Towards the Formation of Dihydrobenzisoxazoles and An Evaluation of the Regioisomeric Bioactivity

Abstract

Here the example of the efficient construction of important dihydrobenzisoxazole cores from the cycloaddition reactions between cyclic diaryl λ3-bromanes as the aryne precursors and nitrones is reported. Many dihydrobenzisoxazole-containing compounds were synthesized under transition-metal-free conditions, and this approach features a broad substrate scope, good functional group compatibility and reasonable regioselectivities. Preliminary bioactivity evaluations demonstrated that multiple examples of these dihydrobenzisoxazoles showed potential activities against porcine reproductive and respiratory syndrome virus (PRRSV).