Abstract:
Hyperpigmentation is a skin problem caused by excessive melanin production by
melanocytes. The aim of products containing tyrosinase enzyme inhibitor compound is to
prevent and overcome skin hyperpigmentation. One of the compounds with tyrosinase
inhibitory activity is pyrazoline which is a five-ring heterocyclic compound with two
nitrogen atoms in its ring. The pyrazoline compound 4-(5-(4-hydroxy-3-methoxyphenyl)-3-
(4-hydroxyphenyl)-4,5-dihydro-1H-pyrazole-1-yl)benzensulfonamide was synthesized
through a cyclization reaction between chalcone compounds and
4-hydrazinylbenzensulfonamide using reflux method. The structure of pyrazoline was
confirmed by UV, FTIR, HRMS and 1H-NMR spectroscopy data analysis. The activity of
synthesized pyrazoline as tyrosinase inhibitor was evaluated by in silico and in vitro assay.
Molecular docking simulation carried out on the tyrosinase crystal structure
(PDB ID: 2Y9X) with kojic acid as positive control. Molecular docking simulation showed
that the synthesized pyrazoline compound had bond free energy
(ΔGbind) = -11.5867 kcal/mol while the free bond energy for kojic acid was
-8.9122 kcal/mol. Furthermore, in vitro assay result showed that pyrazoline compound had
good activity as an inhibitor of the tyrosinase enzyme with value of IC50 16.331 μg/mL.