Facile synthesis and antimicrobial activity of bis(fused 4H‐pyrans) incorporating piperazine as novel hybrid molecules: Michael's addition approach

A new series of bis(4H‐chromene), bis (pyrano[3,2‐c]chromene), and bis (pyrano[2,3‐c]pyrazole) each linked to the piperazine core via ether linkages was synthesized. The target compounds are probably formed through a three‐component reaction involving two equivalents of each malononitrile and the corresponding active methylene compounds, such as dimedone, 4‐hydroxycoumarine, or 5‐methyl‐2,4‐dihydro‐3H‐pyrazol‐3‐one. Several spectral methods and elemental analyses were used to deduce the chemical structures of the novel compounds. Furthermore, all synthesized compounds were tested for antimicrobial activity, which revealed promising inhibitory results against a variety of multidrug‐resistant microbial strains. These findings were compared to those obtained in the in silico molecular docking study. The docking results improved the activity of new derivatives as potentially effective antimicrobial agents. A synthesis of novel bis(4H‐chromene), bis(pyrano[3,2‐c]chromene), and bis(pyrano[2,3‐c]pyrazole) each linked to the piperazine core via ether linkages was described. Antimicrobial activity of the newly synthesized compounds was evaluated.