Synthesis, multiparametric structure assessment and biological evaluation of some new 1,3,4-oxadiazoles containing piperidine nucleus

• Published in: Asian Journal of Chemistry
• Main Author: Iqbal J.; Aziz-Ur-Rehman; Abbasi M.A.; Siddiqui S.Z.; Rasool S.; Rehan M.; Shah S.A.A.
• Format: Article
• Language: English
• Published: Chemical Publishing Co. 2017
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85025480907&doi=10.14233%2fajchem.2017.20564&partnerID=40&md5=430b97b8604685ca9f248bcb082ad364

With an aim to introduce more biologically active compounds, S-substituted derivatives of 5-[1-(4-nitrophenylsulfonyl)piperidin-4-yl]-1,3,4-oxadiazole-2-thiol (3) were synthesized through four steps. In the first step, ethyl 1-(4-nitrophenylsulfonyl)piperidine-4-carboxylate (1)was synthesized by reacting 4-nitrobenzenesulfonyl chloride (a) and ethyl isonipacotate (b) in basic medium. In the second step, compound 1 and hydrazine monohydrate were converted to corresponding hydrazide (2). In third step, hydrazide (2), CS2 and KOH were refluxed in the presence of MeOH to acquire 5-(1-(4-nitrophenylsulfonyl)piperidin-4-yl)-1,3,4-oxadiazole-2-thiol (3). In the last step, alkyl/aralkylhalides (4a-o) and 3 were made to react in an aprotic polar solvent to get the final compounds, 2-(substitutedthio)-5-[1-(4-nitrophenylsulfonyl)piperidin-4-yl]-1,3,4-oxadiazole (5a-o). The synthesized compounds were structurally confirmed by spectroscopic techniques including 1H NMR, EIMS and IR. Finally the synthesized compounds were screened for antibacterial activity against five bacterial strains. © 2017, Chemical Publishing Co. All rights reserved.