Síntese de Hidropiranos Derivados do Ácido Kójico Catalisada por Zeólita NaY à Base de Rejeito de Caulim

Abstract

Kojic acid (KA), known as 5-hydroxy-2-hydroxymethyl-4-pyranone, is a popular ingredient in the cosmetic, pharmaceutical, and medicinal industries due to its depigmenting, antioxidant, and antimicrobial properties. In addition to inhibiting the enzyme tyrosinase, essential for melanin production, KA and its derivatives exhibit broad biological activity, including herbicidal, anti-stain, antitumor, antidiabetic, and antiproliferative effects. Research also suggests its potential application against leishmaniasis, stimulating the phagocytic activity of macrophages, which could help combat the parasite. However, some KA synthesis processes involve high costs and toxic solvents, highlighting the importance of developing more sustainable methods. In this context, this work aims to create KA-derived hydropyrans, promoting a more efficient and transparent synthetic method. Thus, in this work, “green chemistry” concepts were applied to the synthesis of AK results using NaY zeolite based on kaolin waste. Eleven molecules (3a, 3b, 3c, 3d, 3e, 3f, 3g, 3h, 3i, 3j, 3k) were synthesized, all with yields close to or greater than 50%. Only molecule 3k was characterized by 13C and 1H Nuclear Magnetic Resonance (NMR). Based on the above, multicomponent reactions (MCRs) are steps to be performed later to confirm the results obtained and continue this work.