Efficient Synthesis and Antibacterial Evaluation of a Series of Pyrazolylbiscoumarin and Pyrazolylxanthenedione Derivatives

Abstract

Efficient synthesis of a series of pyrazolylbiscoumarin (4a -4e) and pyrazolylxanthenedione derivatives (5a -5e) is described. The structures of the synthesized compounds were confirmed by their spectral data (IR, 1 HNMR and 13 CNMR). All the synthesized compounds 4 and 5 were screened for their antibacterial activity against Gram-positive bacteria S. aureus and Gram-negative bacteria K. pneumoniae. The tested compounds exhibited varying degree of antibacterial activity, showing the inhibition zone size ranging from 6 to 21 mm.

A Synthetic Approach to PW2‐Like Compounds

“…Interconnected ring systems, orientation, aromaticity and heteroatoms are responsible of the ability to bind different receptors that provide a wide spectrum of bioactivities . Between them, xanthene derivatives present different activities including antibacterial, antiviral, antimalarial and anti‐inflammatory …”

“…Interconnected ring systems, orientation, aromaticity and heteroatoms are responsible of the ability to bind different receptors that provide a wide spectrum of bioactivities. [1][2][3][4] Between them, xanthene derivatives present different activities including antibacterial, [5] antiviral, [6] antimalarial [7] and antiinflammatory. [8] 9H-xanthene derivatives, like PW2, PW3, WU5 and WU6 (Figure 1), are interesting examples of this scaffold displaying antiparasitic activity, in particular, toward Plasmodium falciparum, the malaria etiological agent.…”

An Insight View on Synthetic Protocol, Mechanistic and Biological Aspects of Biscoumarin Derivatives

“…Acenes containing biscoumarins are used as semiconductors and have the tendency to reduce oxygen to hydrogen peroxide . Conjugated biscoumarins show wide spectrum of applications like biscoumarin‐iminothiazole conjugates served as alkaline phosphate inhibitory, anti‐cancer and anti‐leishmanial activity, biscoumarin‐thiourea hybrid as α ‐glucosidase inhibitor, biscoumarin‐pyrazole compounds as an antibacterial and used as chemosensor for detection of Zn II and Cu II , thiazolyl‐pyrazole‐biscoumarin structures used as anti‐oxidant and anti‐bacterial and chalcone coupled biscoumarin copolyster have presented anti‐microbial activity and so on. (Figure )…”