Abstract
<jats:p> The synthesis of original tricyclic compounds featuring both 3,4-dihydro- <jats:italic>2H</jats:italic> -benzo[b][1,4] oxazine and cyclopentenone cores was addressed. Starting from the biobased 5-chloromethylfurfural, a robust 3-step sequence to key aryl furylcarbinol substrates supported a diastereoselective intramolecular aza Piancatelli reaction, effective under both Lewis and Brønsted catalysis. A scope of thirteen diversely substituted spirobenzoxazines was targeted and some limits could be also drawn. Seventeen diastereomerically defined spirocyclic molecules were overall isolated. All the synthesized compounds were characterized by NMR analysis. The structure and relative stereochemistry of spirocycles were confirmed by single-crystal X-ray diffraction (XRD) studies. An extension to analogous compound featuring a quinoxaline moiety could also be initiated. Preliminary evaluations of biological activities were performed. </jats:p>