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Synthesis of Triazole Schiff's Base Derivatives and Their Inhibitory Kinetics on Tyrosinase Activity.

Yu F, Jia YL, Wang HF, Zheng J, Cui Y, Fang XY, Zhang LM, Chen QX - PLoS ONE (2015)

Bottom Line: The results together with the anti-tyrosinase activities data indicated that substitution on the second position of benzene ring showed superior ant-ityrosinase activities than that on third position, and that hydroxyl substitutes were better than fluorine substitutes.In addition, two benzene rings connecting to the triazole ring would produce larger steric hindrance, and affect the bonding between tyrosinase and inhibitors to decrease the inhibitory effects.The anti-tyrosinase effects of these compounds were in contrast to their antioxidant activities.

View Article: PubMed Central - PubMed

Affiliation: State Key Laboratory of Cellular Stress Biology, Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen, 361005, China.

ABSTRACT
In the present study, new Schiff's base derivatives: (Z)-4-amino-5-(2-(3- fluorobenzylidene)hydrazinyl)-4H-1,2,4-triazole-3-thiol (Y1), (Z)-3-((2-(4-amino-5- mercapto-4H-1,2,4-triazol-3-yl)hydrazono)methyl)phenol (Y2), (Z)-2-((2-(4-amino-5- mercapto-4H-1,2,4-triazol-3-yl)hydrazono)methyl)phenol (Y3) and 3-((Z)-(2-(4- (((E)-3-hydroxybenzylidene)amino)-5-mercapto-4H-1,2,4-triazol-3-yl)hydrazono)methyl)phenol (Y4) were synthesized and their structures were characterized by LC-MS, IR and 1H NMR. The inhibitory effects of these compounds on tyrosinase activites were evaluated. Compounds Y1, Y2 and Y3 showed potent inhibitory effects with respective IC50 value of 12.5, 7.0 and 1.5 μM on the diphenolase activities. Moreover, the inhibition mechanisms were determined to be reversible and mixed types. Interactions of the compounds with tyrosinase were further analyzed by fluorescence quenching, copper interaction, and molecular simulation assays. The results together with the anti-tyrosinase activities data indicated that substitution on the second position of benzene ring showed superior ant-ityrosinase activities than that on third position, and that hydroxyl substitutes were better than fluorine substitutes. In addition, two benzene rings connecting to the triazole ring would produce larger steric hindrance, and affect the bonding between tyrosinase and inhibitors to decrease the inhibitory effects. The anti-tyrosinase effects of these compounds were in contrast to their antioxidant activities. In summary, this research will contribute to the development and design of antityrosinase agents.

No MeSH data available.


Determinations of the inhibitory mechanisms, types, and constants on diphenolase.(I) The inhibitory mechanisms of the compounds Y1 to Y3. (II) Lineweaver-Burk plots for diphenolase activity. (III) The plots of slopes versus the concentrations of the compounds (IV) The plots of intercepts versus the concentrations of the compounds.
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pone.0138578.g003: Determinations of the inhibitory mechanisms, types, and constants on diphenolase.(I) The inhibitory mechanisms of the compounds Y1 to Y3. (II) Lineweaver-Burk plots for diphenolase activity. (III) The plots of slopes versus the concentrations of the compounds (IV) The plots of intercepts versus the concentrations of the compounds.

Mentions: Under different concentrations of the enzyme, the residual activity of tyrosinase with a fixed amount of substrate was tested. The results were showed in Fig 3AI, 3BI and 3CI. The straight lines 1 to 5 all passed through the origin, which indicated that the inhibitory mechanisms of Y1, Y2 and Y3 on tyrosinase activity were reversible.


Synthesis of Triazole Schiff's Base Derivatives and Their Inhibitory Kinetics on Tyrosinase Activity.

Yu F, Jia YL, Wang HF, Zheng J, Cui Y, Fang XY, Zhang LM, Chen QX - PLoS ONE (2015)

Determinations of the inhibitory mechanisms, types, and constants on diphenolase.(I) The inhibitory mechanisms of the compounds Y1 to Y3. (II) Lineweaver-Burk plots for diphenolase activity. (III) The plots of slopes versus the concentrations of the compounds (IV) The plots of intercepts versus the concentrations of the compounds.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4589318&req=5

pone.0138578.g003: Determinations of the inhibitory mechanisms, types, and constants on diphenolase.(I) The inhibitory mechanisms of the compounds Y1 to Y3. (II) Lineweaver-Burk plots for diphenolase activity. (III) The plots of slopes versus the concentrations of the compounds (IV) The plots of intercepts versus the concentrations of the compounds.
Mentions: Under different concentrations of the enzyme, the residual activity of tyrosinase with a fixed amount of substrate was tested. The results were showed in Fig 3AI, 3BI and 3CI. The straight lines 1 to 5 all passed through the origin, which indicated that the inhibitory mechanisms of Y1, Y2 and Y3 on tyrosinase activity were reversible.

Bottom Line: The results together with the anti-tyrosinase activities data indicated that substitution on the second position of benzene ring showed superior ant-ityrosinase activities than that on third position, and that hydroxyl substitutes were better than fluorine substitutes.In addition, two benzene rings connecting to the triazole ring would produce larger steric hindrance, and affect the bonding between tyrosinase and inhibitors to decrease the inhibitory effects.The anti-tyrosinase effects of these compounds were in contrast to their antioxidant activities.

View Article: PubMed Central - PubMed

Affiliation: State Key Laboratory of Cellular Stress Biology, Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen, 361005, China.

ABSTRACT
In the present study, new Schiff's base derivatives: (Z)-4-amino-5-(2-(3- fluorobenzylidene)hydrazinyl)-4H-1,2,4-triazole-3-thiol (Y1), (Z)-3-((2-(4-amino-5- mercapto-4H-1,2,4-triazol-3-yl)hydrazono)methyl)phenol (Y2), (Z)-2-((2-(4-amino-5- mercapto-4H-1,2,4-triazol-3-yl)hydrazono)methyl)phenol (Y3) and 3-((Z)-(2-(4- (((E)-3-hydroxybenzylidene)amino)-5-mercapto-4H-1,2,4-triazol-3-yl)hydrazono)methyl)phenol (Y4) were synthesized and their structures were characterized by LC-MS, IR and 1H NMR. The inhibitory effects of these compounds on tyrosinase activites were evaluated. Compounds Y1, Y2 and Y3 showed potent inhibitory effects with respective IC50 value of 12.5, 7.0 and 1.5 μM on the diphenolase activities. Moreover, the inhibition mechanisms were determined to be reversible and mixed types. Interactions of the compounds with tyrosinase were further analyzed by fluorescence quenching, copper interaction, and molecular simulation assays. The results together with the anti-tyrosinase activities data indicated that substitution on the second position of benzene ring showed superior ant-ityrosinase activities than that on third position, and that hydroxyl substitutes were better than fluorine substitutes. In addition, two benzene rings connecting to the triazole ring would produce larger steric hindrance, and affect the bonding between tyrosinase and inhibitors to decrease the inhibitory effects. The anti-tyrosinase effects of these compounds were in contrast to their antioxidant activities. In summary, this research will contribute to the development and design of antityrosinase agents.

No MeSH data available.