Synthesis of novel 2-methyl-3-triazolyl chromanone oxime ether derivatives as potential antifungal agents

Background and Despite growing list of antifungal agents, their clinical value has been limited by their relatively high risk of toxicity, the emergence of drug resistance, and insufficiencies in their antifungal activity. This situation has led to an ongoing search for potent broad spectrum antifungal agents with low side effects, which can be administered both orally and parenterally. This paper describes synthesis and structural characterization of 2-methyl-3- triazolyl chromanone oxime ethers as potential antifungal agent. Bromination of 2-hydroxyacetophenones with copper (II) bromide followed by reaction with 1,2,4-triazole gave the corresponding α-triazolyl-2-hydroxyacetophenones, which separated as regioisomers. Ring closure of α-triazolyl-2-hydroxyacetophenones with acetaldehyde in acetic acid gave the corresponding 2-methyl-3-triazolyl chromanones predominantly in the trans configuration. The target compounds (oxime ether derivatives) were prepared by reacting corresponding 2-methyl-3-triazolyl chromanone derivatives with O-benzyl hydroxylamine hydrochlorides in methanol at room temperature. All of the target compounds were characterized by their 1H NMR, IR and mass spectral data. A convenient and efficient synthesis and structural characterization of 2-methyl-3-triazolyl chromanone oxime ether as potential antifungal agents has been achieved. 1H-NMR spectra were generally used to assign the stereochemistry of the isomers (E or Z form) of oxime ethers.