Synthesis of piplartine analogs and preliminary findings on structure–antimicrobial activity relationship
摘要:
In this work it is described the synthesis, characterization and antimicrobial and toxicity evaluation of a series of analogs of piplartine, a piperamide found in Piper sp. The compounds structures were confirmed by infrared spectroscopy, H-1, C-13 nuclear magnetic resonance, high resolution mass spectroscopy and were evaluated against strains of Candida spp., Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. Derivative 24 was almost four-fold more potent (IC50: 48.83 mu M) and five-fold less toxic (SI > 3) than piplartine (IC50: 189.2 mu M; SI: 0.21) against Candida krusei, as well as two-fold more potent than fluconazole (IC50: 104.48 mu M). This compound was also active against Candida tropicalis at 97.67 mu M. Benzoyl derivative 17 was three-fold more potent (IC50: 85.2 mu M) and more than five-fold less toxic (CC50: 231.71 mu M) than piplartine (IC50: 315.33 mu M and CC50: 41.14 mu M) against Staphylococcus aureus. Given these findings, we have found analogs of piplartine which can be assumed as prototypes for the optimization and the development of new antimicrobial (compounds 24 and 17) agents.
A mild and efficient one pot synthesis of 1,3,4-oxadiazoles from carboxylic acids and acyl hydrazides
作者:Hemaka A. Rajapakse、Hong Zhu、Mary Beth Young、Bryan T. Mott
DOI:10.1016/j.tetlet.2006.05.051
日期:2006.7
A convenient one pot method for the synthesis of 2,5-disubstituted 1,3,4-oxadiazoles fromacids and acyl hydrazides is reported. Acid activation with CDI, followed by coupling with the desired acylhydrazide and dehydration in the same pot with Ph3P and CBr4 affords the corresponding 1,3,4-oxadiazoles in good yield. The scope of the acid and acylhydrazide components is presented.
Synthesis and antimycobacterial evaluation of new trans-cinnamic acid hydrazide derivatives
作者:Samir A. Carvalho、Edson F. da Silva、Marcus V.N. de Souza、Maria C.S. Lourenço、Felipe R. Vicente
DOI:10.1016/j.bmcl.2007.11.091
日期:2008.1
evaluation of new trans-cinnamic acidderivatives of isonicotinic acid series (5) and benzoicacid series (6), designed by exploring the molecular hybridization approach between isoniazid (1) and trans-cinnamic acidderivative (3). The minimum inhibitory concentration (MIC) of the compounds 5a-d and 6c exhibited activity between 3.12 and 12.5 microg/mL and could be a good start point to find new lead compounds
Oxidative addition of N-aminophthalimide to 2-alkenyl-1,3,4-oxadiazoles. Synthesis of aziridinyloxadiazoles
作者:O. A. Ignatenko、M. A. Kuznetsov、S. I. Selivanov
DOI:10.1134/s1070428007070172
日期:2007.7
Oxidation of N-aminophthalimide with lead tetraacetate in the presence of 2-[(E)-2-arylethenyl]-5-phenyl-1,3,4-oxadiazoles gives the corresponding 2-(3-aryl-1-phthalimidoaziridin-2-yl)-5-phenyl-1,3,4-oxadiazoles. From 2-phenyl-5-[(1E,3E)-4-phenylbuta-1,3-dien-1-yl]-1,3,4-oxadiazole only the addition product at both C=C bonds was obtained, while in the reaction with 2,5-bis[(E)-2-phenylethenyl]-1,3,4-oxadiazole both mono- and bis-adducts were isolated.