Introduction: The search for bioactive molecules extracted from plants used by American indigenous ethnicities is gaining much consideration as source of new compounds for treating hypertension. Objetive: To evaluate the vascular effect of bioactive molecules isolated and chemically modified from medicinal plants used for the treatment of mountain sickness. Method: We isolated two compounds from Senecio nutans Sch. Bip., such as 4-hydroxy-3-(3-methyl-2-butenyl)acetophenone (metabolite-1) and 6-Hydroxytremetone (metabolite-2). In addition, we carried out chemical modification of both metabolites-1 and -2, which produced oxime-1 and oxime-2, respectively. Vascular reactivity experiments with two metabolites isolated and their oximes in rat aorta were performed. The results obtained from these experiments were expressed as mean ± standard error of mean. Statistical analysis of the data was performed using analysis of variance (two-way ANOVA) where applicable followed by Bonferroni post-hoc test. In addition, the determination of the sensitivity (EC50) was performed using nonlinear regression (sigmoidal) via Graph Pad Prism software, version 5.0. Statistical significance is set at p <0.05. The trials were approved by the Ethics Committee of Universidad Antofagasta (CEC-275/20). Results: All compounds caused vascular relaxation in intact rat aorta pre-contracted with phenylephrine (PE; 10-6 M): 41 ± 6 % metabolite-1, 73 ± 2% oxime-1, 58 ± 2 % metabolite-2, and 48 ± 2 % oxime-2 (10-5 M). The denudation of endothelium in aortic rings provoked a drastic decreased of relaxation induced by the compounds tested in this study. The pre-incubation of the intact aortic rings with 10-4 M L-NAME significantly decreased relaxation in response to all molecules (10-5 M). Moreover, contractile vascular response to PE (EC50 34.04 ± 8.49 nM) was reduced when oxime-1 (EC50 67.28 ± 8.67 nM; p< 0.05) or metabolite-2 (EC50 77.06 ± 7.69 nM; p< 0.01) were present. Conclusion: Since metabolite-2 and oxime-1 showed the highest vascular relaxation effect, they could be potential bioactive molecules for regulating blood pressure.