The effects of ionic strength and temperature on the dissociation constants of adefovir and cidofovir used as antiviral drugs

Authors : Hasan ATABEY, Hayati SARI

Pages : 806-814

Doi:10.3906/kim-1309-39

View : 14 | Download : 7

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :The effects of ionic strength and temperature on the dissociation constants of adefovir insert ignore into journalissuearticles values(PMEA); and cidofovir insert ignore into journalissuearticles values(HPMPC); used as antiviral drugs were studied at 298 K, 308 K, and 318 K in aqueous media and at different ionic strength backgrounds of NaCl potentiometrically. The dissociation constants of the ligands were determined via the calculation of the titration data with the SUPERQUAD computer program. The thermodynamic parameters insert ignore into journalissuearticles values(D G, D H, and D S); for all species were calculated. The dissociation order of nitrogen and oxygen atoms in the ligands according to proton affinities values were obtained using PM6 semiempirical methods. Moreover, pKa values of the ligands were determined at 0.00, 0.10, 0.15, 0.20, and 0.5 mol dm-3 ionic strength insert ignore into journalissuearticles values(NaCl); at 298 K. Consequently, when the ionic strength and temperature in the titration cells were increased, the obtained dissociation constants of PMEA insert ignore into journalissuearticles values(pKa3, pKa4, and pKa5); and HPMPC insert ignore into journalissuearticles values(pKa2 and pKa3); decreased.
Keywords : Adefovir, cidofovir, proton affinities, dissociation constants, thermodynamic parameters