Synthesis, Multiparametric Structure Assessment and Biological Evaluation of Some New 1,3,4-Oxadiazoles Containing Piperidine Nucleus

Abstract

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 1 H NMR, EIMS and IR. Finally the synthesized compounds were screened for antibacterial activity against five bacterial strains.

Nms‐Amides: An Amine Protecting Group with Unique Stability and Selectivity

“…Additional references cited within the Supporting Information. [ 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 ]…”

Versatile Therapeutic Values of N‐Containing Heterocycles Benzimidazole, Piperazine and Piperidine Hybrids

“…Compound 27 exhibited better anticandidal and antifungal activity [77] . Amongst the piperidine‐linked oxadiazole hybrids designed by Javed et al ., Compound 28 exhibited good antibacterial activity against all bacterial strains [78] . Piperidine‐based pyrrolidine hybrids were synthesized by Qing gang et al .…”

“…[77] Amongst the piperidine-linked oxadiazole hybrids designed by Javed et al, Compound 28 exhibited good antibacterial activity against all bacterial strains. [78] Piperidine-based pyrrolidine hybrids were synthesized by Qing gang et al and screened for antifungal activity. Based on screening, compound 29 was reported as the most active antifungal agent against aspergillus flavus with MIC of 0.07 μg/ mL, better than reference fluconazole MIC of 0.209 μg/mL.…”