<p><strong></strong><strong>Objective</strong>. To synthesize and carry out a preliminary evaluation of the <em>in vitro</em> antifungal activity of oximes, oxime ethers and isoxazoles. <strong>Materials and methods</strong>. Oximes were synthesized from aldehydes or ketones with NH<sub>2</sub>OH.HCl and K<sub>2</sub>CO<sub>3</sub>. Oxime ethers were prepared by alkylation of oximes with propargyl bromide or 2-bromobenzyl bromide, using NaOH as base and acetone as solvent. The isoxazoles were obtained by 1,3-dipolar cycloadditions using ceric ammonium nitrate (CAN), chloramine T (CAT) and NaOCl. Products were identified or characterized using nuclear magnetic resonance (NMR) and mass spectrometry (MS). Radial growth inhibition assays against <em>Aspergillus niger</em> and <em>Fusarium roseum</em> were carried out. <strong>Results</strong>. Five oximes, seven oxime ethers, four of them new, and four new isoxazoles were obtained. The assessed substances exhibited antifungal activity in amounts of 1,5 mg and 3,0 mg. <strong>Conclusions</strong>. Although 1,3-dipolar cycloadditions allowed to obtain the desired isoxazoles, this methodology produced a wide variety of side products that reduced yields and made difficult the purification of the target products. Four of the tested compounds showed inhibition percentages greater than 80%.</p> <p><strong>Key words: </strong>oximes, oxime ethers, isoxazoles, antifungal activity.</p> <p> </p><br />