Assessing the pharmacological potential of selected xanthene derivatives

A convenient and efficient approach toward the synthesis of seven aromatically substituted xanthendiones 1-7 and one structurally-related xanthenone 8 through condensation of dimedone and the appropriate aromatic aldehyde is reported. Further, their chemical structure was confirmed by melting points, elemental analysis, FT-IR, H-1-, C-13-NMR and UV-Vis spectroscopic methods. The relationship between the chemical structure and pharmacological activity was determined empirically using appropriate software packages and in vitro using the 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) method. The results of in silico prediction suggested that all investigated com-pounds possess good oral bioavailability. The results of the ABTS assay indicate that five compounds possess the ability to scavenge the ABTS(center dot+) radical cat-ion. Based on the comparison of the IC50 values, the activity of the compounds was found to be as follows: 6 > 1 > 7 > 2 > 8. The effects of solvent dipolarity/polarizability and solute solvent-hydrogen-bonding interactions on the shifts of the absorption maxima were rationalized by means of the linear sol-vation energy relationship concepts proposed by Kamlet-Taft and Catalan.