PREPARATION OF α-ACETYLOXY-N-CYCLOHEXYLAMIDES VIA PASSERINI REACTION USING DIMETHYLCARBONATE AS ECO-FRIENDLY SOLVENT
A series of α-acetyloxy-N-cyclohexylamides was efficiently obtained via Passerini reaction of cyclohexyl isocyanide, acetic acid, and different aromatic and aliphatic aldehydes using refluxing dichloromethane or dimethylcarbonate (DMC). Reactions performed with DMC led to desired products in moderate to good yields, corroborating this solvent as a eco-friendly alternative to the chlorinated solvents commonly used in this transformation. The α-acetyloxy-N-cyclohexylamides thus obtained were tested against Escherichia coli, Bacillus cereus, Pseudomonas aeruginosa, and Staphylococcus aureus, as well as promastigote forms of L.(L.) amazonensis. The α-(Acetyloxy)-N-cyclohexyl-pentanamide showed low antibacterial activity against Gram-positive (S. aureus and B. cereus) and Gram negative (E. coli and P. aeruginosa) bacteria (MIC = 8,3-16,5 mmol L-1), while α-(acetyloxy)-N-cyclohexyl-4-bromo-benzeneacetamide showed leishmanicidal activitity (IC50 = 0,099 mmol L-1).