Cytotoxic and antifungal activity of chalcones synthesized from a natural acetophenone isolated from Croton anisodontus

Resumo

In this work, eight chalcones were synthesized from the 2-hydroxy-3,4,6trimethoxyacetophenone isolated from Croton anisodontus with benzaldehyde and its derivatives as well as evaluated its cytotoxic and antifungal activities. Chalcones were synthesized by the Claisen-Schimdt aldol condensation reaction in basic medium and identified by 1H and 13C NMR, IR and MS. The MTT assay was used to determine the cytotoxicity of all synthetized compounds against human cancer cell lines. The results showed that the % RCV varied from 19.43 ± 1.31 to 75.51 ± 1.84 %. The chalcone (E)-3-(4-fluorophenyl)-1-(2-hydroxy-3,4,6-trimethoxyphenyl)prop-2-en-1-one demonstrated the strongest activity against HCT-116 cells (% RCV = 75.51 ± 1.84). The in vitro antifungal potential of the chalcones showed that chalcones (E)-3-(furan-2-yl)-1-(2-hydroxy-3,4,6-trimethoxyphenyl)prop-2-en-1-one (MIC 0,625 mg/mL against C. albicans LABMIC 0105) and (E)-1-(2-hydroxy-3,4,6-trimethoxyphenyl)-3-(4-methoxyphenyl)prop-2-en-1-one (MIC 0,312 mg/mL against C. albicans LABMIC 0107) were considered as chalcones of better fungal inhibition. The synergistic evaluation in vitro showed no synergistic effect for both chalcones and for kinetics of fungal death, only treatment with chalcone (E)-1-(2-hydroxy-3,4,6-trimethoxyphenyl)-3-(4-methoxyphenyl)prop-2-en-1-one against LABMIC 0107 was able to promote reduction of fungal cells between the periods of 4 to 8 h and 100% inhibition thereafter, resembling the mechanism of action of Amphotericin B.