Direct Synthesis of N‑(1,2,5-Oxadiazolyl)hydrazones through a Diazotization/Reduction/Condensation Cascade
journal contributionposted on 13.11.2020, 15:43 by Dmitry M. Bystrov, Ivan V. Ananyev, Leonid L. Fershtat, Nina N. Makhova
A straightforward synthesis of a series of previously unknown N-(1,2,5-oxadiazolyl)hydrazones through the diazotization/reduction/condensation cascade of amino-1,2,5-oxadiazoles was accomplished. The described protocol was suitable for a wide array of target hydrazones, which were prepared in good to high yields under smooth reaction conditions with very good functional group tolerance. Importantly, the presented approach unveils a direct route to in situ generation of previously inaccessible (1,2,5-oxadiazolyl)hydrazines. In addition, a first example of the ionic structure incorporating a protonated hydrazone motif linked to the 1,2,5-oxadiazole 2-oxide subunit was synthesized, indicating the stability of prepared compounds toward acid-promoted hydrolysis. Overall, this method provides a direct access to the isosteric analogues of drug candidates for treatment of various neglected diseases, thus enabling their potential application in medicinal chemistry and drug design.
Read the peer-reviewed publication
reaction conditionsgenerationseriesstabilityDiazotizationisosteric analoguesarrayoxadiazoleOxadiazolylapplicationdrug candidatesaccessapproachImportantlydiazotizationprotonated hydrazone motif2-subunitmethodsynthesisoxadiazolylCascadecompoundacid-promoted hydrolysisdrug designgroup toleranceyieldcascadeoxideDirect Synthesistarget hydrazones