SYNTHESIS AND BIOLOGICAL INVESTIGATION OF 3,3,6,6- TETRAMETHYL-9-STYRYL-1,8-DIOXOOCTAHYDROXANTHENE PROMOTED BY Fe3O4-SUPPORTED CITRIC ACID AS A MAGNETICALLY RECOVERABLE CATALYST

Abstract

A green and attractive protocol was developed to produce 3,3,6,6-tetramethyl-9-styryl-1,8 dioxooctahydroxanthene using magnetically separable Fe3O4 modified by citric acid (Fe3O4-CA) as catalyst. After catalyst characterization using XRD, Particle Sizer, SEM and EDAX, the Fe3O4-CA was then applied in dioxooctahydroxanthene synthesis with several optimizations, such as % wt. of catalyst, reaction time, temperature and solvent. The best protocol was found when the reaction is conducted using 5% wt. of catalyst at 50oC for 6 h reaction time in methanol, with the highest yield of 80%. The product obtained was confirmed by FTIR, UV-Vis, LC-MS, 1H- and 13C-NMR analysis. In biological investigation, dioxooctahydroxanthene showed higher radical scavenging activity with IC50 of 24.17 ppm, whereas it has comparable antibacterial activity than cinnamaldehyde as its precursor