Pyrazolo[5,1-b]quinazolines and Their Bis-analogues Linked to Different Spacers: Regioselective Synthesis, Antibacterial Screening and SwissADME Prediction Study

A three-component protocol was adopted to efficiently prepare new pyrazolo[5,1-b]quinazolines and their bis-analogues linked to different spacers by o- or p-phenoxy groups. The protocol involved the reaction of the appropriate aldehydes, dimedone, and 1H-pyrazole-3,5-diamine. The new products showed a wide spectrum of antibacterial activity. In general, (4-nitrophenyl)-linked pyrazolo[5,1-b]quinazoline had the best antibacterial activity with MIC/MBC values of 2.1/4.3 μM against S. aureus and P. aeruginosa strains.