Biogenic synthesis of ZnO nanoparticles from Parthenium histerophorus extract and its catalytic activity for building bioactive polyhydroquinolines

In the present protocol, biogenic synthesis of ZnO nanoparticles using an aqueous extract of weed, i.e. Parthenium is efficiently carried out. The proficient and operationally simple catalytic application of biogenic ZnO nanoparticle is explored towards a synthesis of pharmaceutically relevant and densely functionalized polyhydroquinolines by condensation of four components viz. aromatic aldehyde, dimedone, ethyl acetoacetate, and ammonium acetate. The synthesized polyhydroquinolines were screened for their antimicrobial activity against bacteria and fungi; some of them exhibit better to excellent activity. The developed protocol is enriched with captivating advantages such as excellent yields, shorter reaction time, recyclable catalyst and constructive use of an aqueous extract of Parthenium for the synthesis of ZnO nanoparticle. Graphical abstract