Azastilbene Analogs as Tyrosinase Inhibitors: New Molecules with Depigmenting Potential

Abstract

This research has been an effort to develop synthetic resveratrol analogs in order to improve the depigmenting potential of natural resveratrol. Six resveratrol analogs were synthesized and tested for tyrosinase inhibitory activity in vitro, by qualitative and quantitative steps. The results showed the analog C as being the most powerful tyrosinase inhibitor (IA50 = 65.67 ± 0.60 μg/mL), followed by the analogs B, E, F, A, and D, respectively. The analog C presented a tyrosinase inhibition potential better than natural resveratrol (P < 0.001). The best depigmenting activity was provided by the presence of hydroxyl in the orthoposition on the second phenolic ring.

Nobiletin, a Polymethoxy Flavonoid, Reduced Endothelin‐1 Plus SCF‐Induced Pigmentation in Human Melanocytes

“…Active compounds that are commercially used as skin‐whitening agents for treating and preventing hyperpigmentation disorders have caused many side effects including depigmentation in normal skin color as well as skin irritation, contact dermatitis and exogenous ochronosis in dark skin. Because of these problems, their use in cosmetics has been strictly limited, not only in Europe and USA but also in Asia . In light of these concerns, we have carefully evaluated the effects of nobiletin alone in normal human melanocytes.…”

Down-regulation of tyrosinase, TRP-1, TRP-2 and MITF expressions by citrus press-cakes in murine B16 F10 melanoma

“…For example, hydroquinone is a commonly used skin-whitening agent for treating and preventing hyperpigmentation disorders in cosmetic industry, however it has been associated with a lot of side effects, including skin irritation, contact dermatitis, and exogenous ochronosis in dark-skinned people [16] . Therefore, the use of cosmetics containing hydroquinone is prohibited in the European Union and is strictly controlled in the United States by the Food and Drug Administration [16,17] . For that reason, we firstly performed the cell viability of CCE for estimating the in vitro safety, including murine B16F10 melanoma cells and human keratinocyte HaCaT cells in this study.…”

Aza- and Azo-Stilbenes: Bio-Isosteric Analogs of Resveratrol

“…Chelators of copper ions, such as kojic acid ( Figure 6) are good candidates to inhibit tyrosinase action [59]. Given its feature to bind Cu 2+ ion [53], AZA-ST 4a (Figure 6) was evaluated for its ability to inhibit tyrosinase by Lima's group [60]. Compound 4a turned out to provide a lower tyrosinase inhibitory activity than kojic acid; however, compound 4a showed a better depigmenting activity than RSV.…”