Antifungal activities of 2-arylthio-,2-arylthio-5-methoxy-,2,3-bisarylthio-juglones and 2,3-bisarylthio-5,8-dimethoxy-1 A-naphthoquinones

2-Arylthio-, 2-arylthio-5-methoxy-, 2, 3-bisarylthio-juglones and 2, 3-bisarylthio-5, 8-dimethoxy-1, 4-naphthoquinones were newly systhesized for the evaluation of antifungal activities. These derivatives were prepared by methylation of juglone and 2, 3-dichloro-5, 8-dihydroxy-1, 4-naphthoquinone. and by resioselective nucleophilic subsitution with arylthiols. All compounds were tested in vitro for their growth inhibitory activities against pathogenic fungi by the standard method. The MIC values were determined by comparison to flucytosine as a fungicidal standard agent. In general. In general. most juglone derivatives shows in vitro antifungal activities. Among them. 2-arylthio-5-methoxy-juglones showed most potent antifungal activities against all pathogenic fungi.