Synthesis of certain new fused pyranopyrazole and pyranoimidazole incorporated into 8-hydroxyquinoline through a sulfonyl bridge at position 5 with evaluation of their in-vitro antimicrobial and antiviral activities

Kassem, Emad M.; El-Sawy, Eslam R.; Abd-Alla, Howaida I.; Mandour, Adel H.; Abdel-Mogeed, Dina; El-Safty, Mounir M.

doi:10.7123/01.EPJ.0000421482.33940.0b

Synthesis of certain new fused pyranopyrazole and pyranoimidazole incorporated into 8-hydroxyquinoline through a sulfonyl bridge at position 5 with evaluation of their in-vitro antimicrobial and antiviral activities

Authors

10.7123/01.EPJ.0000421482.33940.0b

Abstract

Background and objectives
Heterocyclic systems with a quinoline nucleus display a wide spectrum of biological activities such as antimicrobial and antiviral activities. The aim of the present study was the synthesis of new fused pyranopyrazoles, and , and pyranoimidazoles, and , incorporated to 8-hydroxyquinoline through a sulfonyl bridge at position 5 and evaluation of their antimicrobial and antiviral activities.
Methods
The synthesis of the titled quinoline derivatives was achieved through cyclization of 8-hydroxyquinoline-5-sulfonyl chloride () with 2º-acetyl-2-cyanoacetohydrazide, 2-cyanoacetic acid hydrazide, and 3-amino-5-pyrazolone to afford , , and , respectively. Moreover, reaction of with glycine gives , which on heterocyclization with ammonium thiocyanate yielded the 2-thioxoimidazolidin-2-one derivative . Cyclocondensation reaction of , , , and with different arylidene malononitriles afforded fused systems, , , , and , respectively. The synthesized compounds were evaluated for their in-vitro antimicrobial activity using the disc diffusion method. In addition, they were evaluated for their in-vitro antiviral activity against avian paramyxovirus type 1 (APMV-1) and laryngotracheitis virus (LTV).
Results and conclusion
In-vitro antimicrobial activity of the newly synthesized compounds included an inhibitory effect toward the growth of and (Gram-negative bacteria). Furthermore, of the six selected compounds (, , , , and ) tested for their antiviral activity, compounds , , and at a concentration range of 3–4 µg/ml showed marked viral inhibitory activity for APMV-1 of 5000 tissue culture infected dose fifty (TCID) and LTV of 500 TCID in Vero cell cultures on the basis of their cytopathic effect. Chicken embryo experiments show that compounds , , and possess high antiviral activity , with inhibitory concentration fifty (IC) ranging from 3 to 4 µg/egg against avian APMV-1 and LTV and toxic concentration fifty (CC) ranging from 200 to 300 µg/egg.

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