Metastatic melanoma patients have a poor prognosis with poor responsiveness to chemotherapy. BRAF V600E mutations have been detected in ~40% of melanoma patients. Vemurafenib is an oral agent licensed for patients with BRAF V600E mutation-positive inoperable and metastatic melanoma, which already presents resistance that leads to patient relapse and the serious side effects. In our study, we synthesized 5 new vemurafenib analogs, RF-86A, RF-87A, RF-94A, RF-94B and RF-96B, with structural improve-ments, in order to increase the anti-proliferative and anti-metastatic effect on human melanoma. We showed that the analogs were efficient in inducing cell death and reducing the migration of A375 cells, by inhibition of MMP-2 and MMP-9 activity, indicating that this action may be longer lasting comparing to the action of Vemurafenib.

Parkinson's disease (PD) is a degenerative disease that affects approximately 6.1 million and is primarily caused by the loss of dopaminergic neurons. Naphthoquinones have several biological activities explored in the literature, including neuroprotective effects. Therefore, this review shows an overview of natural and synthetic naphthoquinones with neuroprotective effects and with potential for the development of molecules for the treatment of PD. Many examples of natural naphthoquinones, such as shikonin, plumbagin and vitamin K, exerted a neuroprotective effect by preventing oxidative stress, in addition to multiple mechanisms. Synthetic naphthoquinones with inhibitory activity on the P2X7 receptor were also found, leading to a neuroprotective effect on Neuro-2a cells. It was found that naphthazarin can act as inhibitors of the MAO-B enzyme. Vitamin K and synthetic naphthoquinones hybrids with tryptophan or dopamine showed inhibition of the aggregation of α-synuclein. A library of synthetic derivatives of juglone and naphthazarin were able to protect Neuro-2a cells against neurodegenerative effects of neurotoxins. We report many examples of naphthoquinones that act in therapeutic pathways for the treatment of PD. In addition, routes for producing synthetic derivatives were also discussed. With the data presented, 1,4-naphthoquinones can be considered a promising class in the treatment of PD.