Potent antimicrobial agents against azole-resistant fungi based on pyridinohydrazide and hydrazomethylpyridine structural motifs
摘要:
Schiff base derivatives have recently been shown to possess antimicrobial activity, and these derivatives include a limited number of salicylaldehyde hydrazones. To further explore this structure-activity relationship between salicylaldehyde hydrazones and antifungal activity, we previously synthesized and analyzed a large series of salicylaldehyde and formylpyridinetrione hydrazones for their ability to inhibit fungal growth of both azole-susceptible and azole-resistant species of Candida. While many of these analogs showed excellent growth inhibition with low mammalian cell toxicity, their activity did not extend to azole-resistant species of Candida. To further dissect the structural features necessary to inhibit azole-resistant fungal species, we synthesized a new class of modified salicylaldehyde derivatives and subsequently identified a series of modified pyridine-based hydrazones that had potent fungicidal antifungal activity against multiple Candida spp. Here we would like to present our synthetic procedures as well as the results from fungal growth inhibition assays, mammalian cell toxicity assays, time-kill assays and synergy studies of these novel pyridine-based hydrazones on both azole-susceptible and azole-resistant fungal species. (C) 2015 Elsevier Ltd. All rights reserved.
Indium(I)-Catalyzed Asymmetric Allylation, Crotylation, and α-Chloroallylation of Hydrazones with Rare Constitutional and High Configurational Selectivities
The hydra‐zone: The first example of asymmetric InI catalysis had been developed. InI combined with a chiral semicorrin ligand (L*) is an effective catalyst for enantioselective allylation, crotylation, and α‐chloroallylation of hydrazones. In the two latter cases, CC bond formations proceeded with highselectivity where both reactive aliphatic CCl and aromatic OH bonds were tolerated.
Convenient preparation of unsymmetrical 2,5-disubstituted 1,3,4-oxadiazoles promoted by Dess–Martin reagent
作者:Cristian Dobrotă、Codruţa C. Paraschivescu、Ioana Dumitru、Mihaela Matache、Ion Baciu、Lavinia L. Ruţă
DOI:10.1016/j.tetlet.2009.02.054
日期:2009.4
2,5-Disubstituted 1,3,4-oxadiazoles have been conveniently prepared by oxidative cyclization of N-acyl-N'-aryliden-hydrazines promoted by all excess or Dess-Martin periodinane under Mild conditions (23 examples, up to 92% isolated yields). (C) 2009 Elsevier Ltd. All rights reserved.