Synthesis of novel compounds containing morpholine and 5(4H)-oxazolone rings as potent tyrosinase inhibitors.

In this study, six new compounds containing morpholine and 5(4H)-oxazolone rings were synthesized. Structures of the new compounds using IR, (1)H NMR, mass spectroscopy and elemental analysis were characterized. All new compounds (4a-4f) have a strong inhibitory effect against mushroom tyrosinase. And the inhibitory effects of these compounds were compared with Kojic acid as standard.

Synthesis of novel compounds as new potent tyrosinase inhibitors.

In the present paper, we report the synthesis and pharmacological evaluation of a new series of azo compounds with different groups (1-naphthol, 2-naphthol, and N,N-dimethylaniline) and trifluoromethoxy and fluoro substituents in the scaffold. All synthesized compounds (5a-5f) showed the most potent mushroom tyrosinase inhibition (IC50 values in the range of 4.39 ± 0.76-1.71 ± 0.49 µM), comparable to the kojic acid, as reference standard inhibitor. All the novel compounds were characterized by FT-IR, ¹H NMR, ¹³C NMR, and elemental analysis.

Synthesis of novel azo compounds containing 5(4H)-oxazolone ring as potent tyrosinase inhibitors.

Six new azo dyes containing of 5(4H)-oxazolone ring were prepared by diazotization of 4-aminohippuric acid and coupling with N,N-dimethylaniline, 1-naphthol and 2-naphthol and condensation with 4-fluoro benzaldehyde or 4-trifluoromethoxy benzaldehyde. The new compounds were fully characterized by spectroscopic techniques. All synthesized compounds exhibited high tyrosinase inhibitory behavior. The results of mushroom tyrosinase inhibition assays indicate that the 4-trifluoromethoxy derivatives have high degrees of inhibition and N,N-dimethylaniline derivatives are better for tyrosinase inhibition than 1-naphthol and 2-naphthol derivatives. All synthesized azo compounds (4a-4f) showed the most potent mushroom tyrosinase inhibition, comparable to that of Kojic acid and l-mimosine, as reference standard inhibitors.