Determination of potential solvents for novel N-substituted 5-(phenylamino)uracil derivatives and evaluation of their cytotoxic effects on Vero 76 Cells

N-substituted 5-(phenylamino)uracil derivatives have recently shown to possess potential antiviral properties. However, the high lipophilicity of these compounds has limited their ability to be dissolved in aqueous media for further in vitro and in vivo studies. This study aimed to determine the potential solvents for novel N-substituted 5-(phenylamino)uracil compounds and to evaluate the cytotoxic effects of these solvents on Vero 76 cells. Eight solvents, namely acetone, methanol, ethanol, dimethyl sulfoxide (DMSO), polyvinylpyrrolidone, nicotinamide, L-arginine, and sodium benzoate, were used to dissolve 1600 µM each of compound Z214 and compound Z276, which were chosen as the representatives of novel N-substituted 5-(phenylamino)uracil derivatives. Only L-arginine (700 mM), sodium benzoate (1500 mM), and DMSO (128 mM) were able to solubilise both compounds. Cytotoxicity assays on Vero 76 cells have shown that the maximum concentrations of L-arginine, sodium benzoate, and DMSO that demonstrated 100% cell viability were 108 mM, 10 mM, and 211 mM respectively. L-arginine at concentrations ranged from 215 mM to 860 mM have shown to significantly increased cell proliferation; while both sodium benzoate and DMSO have significantly reduced cell viability at concentrations = 10 mM and = 211 mM respectively. CC50 values were 23.22 mM and 214.92 mM for sodium benzoate and DMSO respectively. The findings in this study revealed that DMSO at a concentration of 211 mM was found to be the most appropriate solvent to solubilise 1600 µM and below of novel N-Substituted 5-(phenylamino)uracil derivatives. © 2019, University of Malaya. All rights reserved.