α-Glucosidase inhibition assay of galbanic acid and it amide derivatives: New excellent semi-synthetic α-glucosidase inhibitors.

α-Glucosidase inhibitory activity of galbanic acid and its new amide derivatives 3a-n were investigated. Galbanic acid and compounds 3a-n showed excellent anti-α-glucosidase activity with IC50 values ranging from 0.3 ± 0.3 µM to 416.0 ± 0.2 µM in comparison to positive control acarbose with IC50 value of = 750.0 ± 5.6. In the kinetic study, the most potent compound 3h demonstrated a competitive mode of inhibition with Ki = 0.57 µM. The interaction of the most potent compound 3h with the α-glucosidase was further elaborated by in vitro Circular dichroism assessment and in silico molecular docking and Molecular dynamics studies. Compound 3h was also non-cytotoxic on human normal cells. In silico study on pharmacokinetics and toxicity profile of the most potent galbanic acid derivatives demonstrated that these compounds are valuable lead compounds for further study in order to achieve new anti-diabetic agents.

Evaluating the effects of disubstituted 3-hydroxy-1H-pyrrol-2(5H)-one analog as novel tyrosinase inhibitors.

In the present study, a series of 3-hydroxy-1H-pyrrol-2(5H)-one derivative were rationally designed and synthesized. The structure of targeted compounds was confirmed by IR, 1H NMR, 13C NMR, and elemental analysis. Next, all derivatives were evaluated as tyrosinase inhibitors, and among the synthesized derivatives, compound 6a was proved to be the most potent inhibitor with an IC50 value of 6.98 ± 1.05 µM. Kinetic study of compound 6a confirmed the mixed type of inhibitory activity towards tyrosinase. Furthermore, the results of the molecular docking study showed that this compound fitted well in the active site of tyrosinase and exhibited interaction with important residues of the binding site.