Elucidating the selectivities and the mechanism of [3+2] cycloloaddition reaction between 9α-hydroxyparthenolide and 4-methylbenzene-nitrile-oxide

•An exploration of conceptual DFT indices indicates that 4-methyl-Benzonitrile-N-oxide will engage in this reaction as a nucleophile, whereas 9α-hydroxyparthenolide (2) will pay as an electrophile.•The ELF examination divulges that this reaction follows a two-step reaction mechanism.•The 1,3-dipolar cycloaddition reaction in the treatment of mycrobacterial infections like tuberculosis and diseases like hepatitis.•The biological results allow us to validate the docking protocol.