Bleaching Activity of 4-Phenyl-3-(substituted benzylthio)-4H-1,2,4-triazoles

Abstract

A variety of 4-aryl-and 4-alkyl-3-(substituted benzylthio)-4H-1,2,4-triazoles were prepared and evaluated for their bleaching activity by the lettuce seedling test. Among the series of tested compounds, 4-(3-‰uoro-phenyl)-3-(4-tri‰uoromethylbenzylthio)-4H-1,2,4-triazole (39) exhibited the highest bleaching activity, causing complete bleaching symptoms at 10 mM. In the dark condition, compound 39 inhibited the formation of such carotenoids as b-carotene, violaxanthin, neoxanthin and lutein, resulting in the formation of z-carotene, phytoene, phyto‰uene and b-zeacarotene, which were not detected in the untreated control. Treatment by compound 39 at 50 mM resulted in the amount of accumulated z-carotene being seven-fold higher than that of phytoene, phyto‰uene and b-zeacarotene. These results suggest that compound 39 might have interfered with desaturation, especially z-carotene desaturation, during carotenoid biosynthesis.

Discovery of (5-(Benzylthio)-4-(3-(trifluoromethyl)phenyl)-4H-1,2,4-triazol-3-yl) Methanols as Potent Phytoene Desaturase Inhibitors through Virtual Screening and Structure Optimization

“…In the past decades, seven kinds of PDS-targeted bleaching herbicides have been commercialized. − According to the structural features, these herbicides can be subdivided into three classes: phenyl-ether (diflufenican, beflubutamid, picolinafen), N -phenyl heterocycle (norflurazon and fluorochloridone), and diphenyl heterocycle (flurtamone and fluridone) . Norflurazon as one of the PDS inhibitors was applied at a dosage up to 2000 g/ha .…”