Synthesis and antimicrobial evaluation of some 2,5 disubstituted 1,3,4-oxadiazole derivatives

Abstract

1,3,4-oxadiazoles are interesting compounds because of their valuable biological effects such as cytotoxic, antibacterial, antifungal, and anti-tubercular activities. Ethyl mandelate was treated with hydrazine hydrate to yield the corresponding acylhydrazide. Some of the 2,5 disubstituted 1,3,4-oxadiazole derivatives were prepared from acylhydrazide using three different procedures. In the first procedure, acylhydrazide was reacted with nitro or chloro aroyle chloride to afford a diacylhydrazide which was cyclized to 2,5-disubstituted 1,3,4-oxadiazole in the presence of phosphoryl chloride as dehydrating agent. In the second procedure, furan-oxadiazole derivative was directly prepared from carboxylic acid and acylhydrazide in one step. In the third procedure, acyl hydrazide was condensed with 5-nitrofuraldehyde to yield 5-nitrofuran-2-yl) methylene)-2-phenyl acetohydrazide intermediate which was cyclized to form the nitrofuran-oxadiazole derivative by acetic anhydride as dehydrating agent. The structures of these compounds have been elucidated by spectral IR and 1H-NMR analysis. All the newly synthesized compounds were screened for their antibacterial and antifungal activities. Compounds F3 and F4 showed remarkable antibacterial activities against Staphylococcus aureus and Escherichia coli bacteria.

Synthesis, cytotoxic evaluation, and molecular docking studies of some new 1, 3, 4-oxadiazole-based compounds

“…A literature survey reveals that 1, 3, 4- oxadiazole is an interesting heterocyclic scaffold for the development of new anticancer agents ( 28 30 31 ). In the present study, some amide and imine derivatives of oxadiazole were synthesized in two steps, along with some previously prepared oxadiazole derivatives ( 17 ), and the cytotoxic effects were evaluated on two cell lines at different concentrations.…”

“…The crystal structure of EGFR tyrosine kinase with its ligand (PDB ID: 1M 17) with resolution 2.6 Å was downloaded from the protein data bank ( www.rcsb.org ) ( 4 23 ). Compounds IIa-d and IIe, f , and i ( 17 ) were subjected to molecular docking studies using autodock 4 software.…”

“…Some of these compounds showed promising in vitro antitumor activity against several cell lines ( 3 ). In view of the above mentioned facts and as an attempt to obtain new anticancer agents, in the present research, a series of 2, 5-disubstituted 1, 3, 4- oxadiazol derivatives were synthesized ( Ila-d ), along with some previously prepared oxadiazole derivatives ( Ile, f, and i ) ( 17 ), and evaluated for cytotoxic activity against MCF-7 and HeLa cell lines.…”

Synthesis and cytotoxic activity evaluation of some new 1, 3, 4-oxadiazole, 1, 3, 4-thiadiazole and 1, 2, 4- triazole derivatives attached to phthalimide

“…Five-membered heterocyclics are used as a pivotal scaffold of many compounds in medicinal chemistry due to their similarity with biologically active compounds within our body and provide a wide range of biological activities such as anticonvulsant, anticancer, antimicrobial, and anti-inflammatory effects ( 2 3 ). In this family, azoles, including 1, 3, 4-oxadiazoles, 1, 3, 4-thiadiazoles and 1, 2, 4-triazoles have been involved as “privileged” construction in plentiful therapeutic areas particularly anticancer chemotherapy ( 2 3 4 5 6 7 8 9 ). Literature survey indicated that a minor alteration in the structure of 1,3, 4-oxadiazoles, 1,2, 4-triazoles and 1,3, 4-thiadiazines can lead to changes in their biological activities ( 10 ).…”

Synthesis and Characterization of New 2-(2-Thienyl)-5- Aryl-1,3,4-Oxadiazoles

“…1,3,4-Oxadiazole heterocyclic core is a versatile lead molecule for designing several potential bioactive agents. 1,3,4-Oxadiazole derivatives are reactive pharmacophores and exhibit a wide range of biological activities including antibacterial [3,4,7], antitubercular [10], antifungal [13,18], antiviral [8], cytotoxic [15], anticancer [9,17], anti-inflammatory and analgesic [2,11,22] activities. A variety of therapeutically active agents such as raltegravir (antiretroviral drug), zibotentan (anticancer agent), furamizole (nitrofuran antibacterial agents), tiodazosin and nesapidil (antihypertensive agents) are based on 1,3,4-oxadiazole moiety [23].…”