Novel anticancer candidates: synthesis and antitumor activity of capsaicin-like sulfonate and sulfonamide analogues.

Author(s)

Mauricio Temotheo Tavares

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Conjunto das Químicas (IQ e FCF) (CQ/DBDCQ)
• Defense date: 2014-09-01

Examining board members

Roberto Parise Filho; Elizabeth Igne Ferreira; Julio Cezar Pastre

• Advisor: Roberto Parise Filho

Abstract

Cancer is the second most lethal group of diseases all over the world, just behind cardiovascular diseases. This scenery is worrying in Brazil due the pronounced aging trend observed, that presents the higher incidence of cancer. In this context, the current anticancer therapy still have several biases regarding toxicity and selectivity. Many current medicines correlate to natural products, even in its early stages of development, which highlight the importance of natural sources in the design of new bioactive compounds. Capsaicin is the substance responsible for the pungency of Capsicum genus\' chili peppers. Capsaicin has been shown as an important natural agent because of its cytotoxic activity against several tumor cell lines. However, the pungency and poor stability presented by capsaicin restricts its therapeutic employments. Thus, the capsaicinoid scaffold has a great potential to inspire the design of new bioactive analog entities to be employed in anticancer therapy. This project aimed at designing and synthesizing sulfonamide and sulfonate analogues of capsaicin, performing molecular changes on capsaicinoid core. After a single step synthesis, the analogues were purified and characterized by melting point, 1H/13C NMR and elementary analysis. Subsequently, cytotoxicity assays were performed by MTT method on tumor cell lines MDA-MB-231 and MCF-7 (breast cancer), B16-F10 (murine melanoma) and on healthy fibroblast (3T3). Four compounds showed interesting biological activity at micromolar concentrations (µM) and their IC50 were lower than that presented by capsaicin. The most active compounds, RPF-101 and RPF-151, had their death induction mechanisms investigated. In silico subsequent studies with the most active compounds (RPF-101 and RPF-151) showed that molecular changes promoted on each one increased their hydrophilicity and raised their dipole moment, which may be related to the improvement on biological activity of both. The evaluation of active compounds for Lipinski´s Rule of Five (RO5) properties revealed that they respect all properties presenting its druglikeness for oral administration since RPF151 did not presented in vivo pungency. The RPF-101 and RPF-151 indicate the success obtained by the structural optimization promoted on capsaicinoid scaffold and emphasizes the potential of these analogues to inspire the designing of new future optimized structures, with greater potency and less associated toxicity. (AU)

• FAPESP's process: 12/23233-8 - Novel anticancer candidates: synthesis and antitumoral activity of capsaicin-like sulfonate and sulfonamide analogues
• Grantee: Maurício Temotheo Tavares
• Support Opportunities: Scholarships in Brazil - Master