New group of azastilbene analogs of resveratrol: Synthesis, anticandidal activity and toxicity evaluation

Abstract

Infections caused by microorganisms of the Candida genus represent a major cause of morbidity and mortality among the population. Therefore, this study aimed at evaluating the antifungal activity and toxicity of resveratrol-analog Schiff bases. Faced with Candida albicans ATCC 10,231, the broth microdilution method was used, along with amphotericin B as the reference drug. The toxicity was evaluated in human keratinocyte cells and against Artemia salina. All analogs were active against the microorganism and caused structural changes in the yeast. The minimum inhibitory concentration was lower for analog A (156.3 µg mL−1), followed by B (312.5 µg mL−1), C (312.5 µg mL−1) and D (625 µg mL−1); while the minimum fungicidal concentration was lower for A (1,250 µg mL−1), B (1,250 µg mL−1) and D (1,250 µg mL−1), followed by C (2,500 µg mL−1). In keratinocytes, the compounds presented cell viability between 50.9 and 93%. Against A. salina, the compounds presented moderate cytotoxic activity. The compound with the nitro group, an electron withdrawing group, in the para position presented better antifungal activity. Resveratrol analogs can be promising in the development of new antifungal agents. Keywords: Resveratrol analogs, Schiff bases, Candida albicans, Antifungal activity, Toxicity