Synthesis and Antimicrobial Activity of 3-Aryland 3-Arylmethyl-Cyclopenta[c]Pyrazoles and -Cyclopenta[d ]Isoxazoles

Abstract

Acylation of 1-piperidinocyclopentene by aromatic and arylacetic acid chlorides synthesized the corresponding 1,3-diketones that were reacted with hydrazine hydrate to give 3-aryl- and 3-arylmethylcyclopenta[c]pyrazoles and with hydroxylamine to give the corresponding cyclopenta[d]isoxazoles. The diketones and heterocyclic compounds prepared from them exhibited weak inhibitory activity against Staphylococcus aureus and Escherichia coli. The starting diketone containing a p-NO₂ group was the most active compound with a minimum inhibitory concentration of 125 μg/mL.