RESUMEN: En este trabajo se describe la síntesis de hidrazonas derivadas de cromano, tiocromano, alquil y aril hidrazonas, su actividad leishmanicida y su efecto sobre proteasas de cisteína de L. (V) panamensis. Se sintetizan feniltiocromanos y bencil y naftil derivados; solamente las fenilhidrazonas muestran alguna actividad sobre amastigotes de Leishmnia (V) panamensis. No se observa ningún efecto sobre una proteasa de cisteína del parásito lo que sugiere un mecanismo de acción diferente a la inhibición de esta enzima.ABSTRACT: In this paper, the synthesis of hydrazones derived from cromano, thiocroman, alkyl and aril hydra-zones is described, as well as their leishmanicidal activity and their effect on cysteine proteases fromL. (V) panamensis. A series of novel phenylthiochromane and benzyl and naphtyl derivatives are synthesized and evaluated for their cytotoxic and antileishmanial activities. Their effect on parasite cysteine protease is also evaluated. Only phenylthiochromane derivatives display some activity againstLeishmania (V) panamensisbut all compounds are inactive against parasitic cystein protease. These results may suggest a different mechanism of action for these compounds.COL0015339COL0015099